Yesterday I highlighted the paper The extra-tropical Northern Hemisphere temperature in the last two millennia: reconstructions of low-frequency variability, by B Christiansen of the Danish Meteorological Institute and F C Ljungqvist of Stockholm University which showed that using a multitude of proxy samples in the norther hemisphere, that:
“The level of warmth during the peak of the MWP (Medieval Warm Period) in the second half of the 10th century, equaling or slightly exceeding the mid-20th century warming, is in agreement with the results from other more recent large-scale multi-proxy temperature reconstructions.”
Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.
Variability and extremes of northern Scandinavian summer temperatures over the past two millennia
Jan Esper, Ulf Büntgen, Mauri Timonen, David C. Frank
Abstract
Palaeoclimatic evidence revealed synchronous temperature variations among Northern Hemisphere regions over the past millennium. The range of these variations (in degrees Celsius) is, however, largely unknown. We here present a 2000-year summer temperature reconstruction from northern Scandinavia and compare this timeseries with existing proxy records to assess the range of reconstructed temperatures at a regional scale. The new reconstruction is based on 578 maximum latewood density profiles from living and sub-fossil Pinus sylvestris samples from northern Sweden and Finland.
The record provides evidence for substantial warmth during Roman and Medieval times, larger in extent and longer in duration than 20th century warmth.
The first century AD was the warmest 100-year period (+0.60 °C on average relative to the 1951–1980 mean) of the Common Era, more than 1 °C warmer than the coldest 14th century AD (−0.51 °C). The warmest and coldest reconstructed 30-year periods (AD 21–50=+1.05 °C, and AD 1451–80=−1.19 °C) differ by more than 2 °C, and the range between the five warmest and coldest reconstructed summers in the context of the past 2000 years is estimated to exceed 5 °C. Comparison of the new timeseries with five existing tree-ring based reconstructions from northern Scandinavia revealed synchronized climate fluctuations but substantially different absolute temperatures. Level offset among the various reconstructions in extremely cold and warm years (up to 3 °C) and cold and warm 30-year periods (up to 1.5 °C) are in the order of the total temperature variance of each individual reconstruction over the past 1500 to 2000 years. These findings demonstrate our poor understanding of the absolute temperature variance in a region where high-resolution proxy coverage is denser than in any other area of the world.
[…]
Discussion and Conclusions
The MXD-based summer temperature reconstruction presented here sets a new standard in high-resolution palaeoclimatology. The record explains about 60% of the variance of regional temperature data, and is based on more high-precision density series than any
other previous reconstruction. Importantly, MXD sample replication prior to the Little Ice Age, during Medieval times and throughout the first millennium AD, is much better than in any other record, and we demonstrated – based on calibration trials using reduced
datasets – that these early sections of the N-Scan record likely still contain useful climate information. This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.
According to this new record, summer temperatures varied by 1.1 °C among the 14th and 1st centuries, the coldest and warmest 100-year periods of the past two millennia. Temperatures ranged by more than 5 °C among the five coldest and warmest summers of the past 2000 years. These estimates are, however, related to the approach used for proxy transfer, i.e. figures would change, if the calibration method, period, and/or target were modified (Frank et al.,2010b). For example, variance among the 30 coldest and warmest N-Scan summers (Table 3) increases from 3.92 °C to 5.79 °C, if scaling (i.e. adjustment of the mean and variance) instead of OLS regression is used for proxy transfer. These differences between scaling- and regression-based approaches are proportional to the unexplained variance of the calibration model (Esper et al., 2005), and we suggest
smoothing the proxy and instrumental timeseries prior to calibration, as this procedure decreases the unexplained variance in all Scandinavian tree-ring records and thus minimizes the differences between various calibration methods (Cook et al., 2004).
Our results, however, also showed that these methodological uncertainties are dwarfed by the variance among the individual reconstructions.
Differences among six northern Scandinavian tree-ring records are>1.5° in 30-year extreme periods and up to 3 °C in single extreme years, a finding we didn’t expect, as the proxy records: (i) all calibrate well against regional instrumental data, (ii) partly share the same measurement series (or use differing parameters – TRW and MXD – from the same trees), and (iii) originate from a confined region in northern Scandinavia that is characterized by a homogeneous temperature pattern. Since we here calibrated all reconstructions using the same method, between-record differences are likely related to varying data treatment and chronology development methods, measurement techniques, and/or sampling strategies, as well as the remaining uncertainty typical to such proxy data. For example, splicing of MXD data on recent TRW trends as done in Briffa92 might have caused this reconstruction to appear at the lower (colder) end of the ensemble, whereas the combination (and adjustment) of novel digital MXD measurements with traditional X-ray based MXD data as done in Grudd08 might have caused this reconstruction to appear at the upper (warmer) end of the ensemble. Other differences are likely related to the combination of sub-fossil material from trees that grew in wet conditions at the lakeshores with material from living trees growing in dryer ‘inland’ sites. Also varying variance stabilization (Frank et al., 2007) and detrending techniques (Esper et al., 2003) in association with temporally changing sample replications and age distributions of the underlying data (Melvin, 2004) likely impacted the variance structure of the long-term records and consequently the absolute levels of reconstructed temperatures.
Between-reconstruction variance as revealed here represents a pending challenge for the integration of proxy records over larger regions and the development of a single timeseries that represents the Northern Hemisphere (e.g., Mann et al., 2008), for example. The composition of such records commonly relies on the calibration statistics derived from fitting regional proxy records against instrumental data (D’Arrigo et al., 2006). However, the records analyzed here would all easily pass conventional calibration-based screening procedures. Yet our analysis revealed that choosing one Scandinavian record instead of another one can alter reconstructed temperatures by 1.5-3 °C during Medieval times, for example. On the other hand, consideration of all records presented here would likely promote a less variable climate history, as the combination of diverging records tends to reduce variance in the mean timeseries (Frank et al., 2007). If such a mean is then combined with instrumental data covering the past 100–150 years, this approach might facilitate hockey stick-shaped reconstructions (Frank et al., 2010a). This seems to be a tricky situation in which expert teams including the developers of proxy records might need to be involved to help assessing timeseries beyond the typical ranking based on calibration statistics.
Our results showed that introducing an improved temperature reconstruction does not automatically clarify climate history in a given region. In northern Scandinavia, we now arrive at a situation where a number of high-resolution proxy records – all passing classical calibration and verification tests – are available within a confined region that is characterized by homogeneous temperature patterns. These records, however, differ by several degrees Celsius over the past two millennia, which appears huge if compared with the 20th Century warming signal in Scandinavia or elsewhere. We conclude that the temperature history of the last millennium is much less understood than often suggested, and that the regional and particularly the hemispheric scale pre-1400 temperature variance is largely unknown. Expert teams are needed to assess existing records, and to reduce uncertainties associated with millennium-length temperature reconstructions, before we can usefully constrain future climate scenarios.
Full paper here (PDF -link fixed)
h/t to WUWT reader Gordon Pye and Tory Aardvarrk
I wonder if this will make it to the IPCC’s AR5 next year.
Taking any bets?
Kurt in Switzerland
Just a note. As far as I understand it, the reconstruction is the same as used in Esper et al. 2012 in Nature Climate Change
I think Figure 6 is interesting.
Clearly, the following applies here:
1. The data has not been subjected to interpretation by Mannian mathematics.
2. It will be ignored by the alarmist community, especially the IPCC, and/or
3. It will be condemned by the alarmist community as being not representative – northern Scandinavia only.
There are some river banks in southern Iceland, where I have seen the remains of huge tree trunks, clear evidence of much warmer conditions than today.
Icelandic joke: “What do you do if you get lost in an Icelandic forest?” Answer: “Stand up.”
Your link to the PDF of the paper is broken.
Thanks
JK
Between-reconstruction variance as revealed here represents a pending challenge for the integration of proxy records over larger regions and the development of a single timeseries that represents the Northern Hemisphere
There is a single proxy for whole of the northern hemisphere: geo-solar oscillations or interaction between changes in the solar activity and the Earth’s interior periodic undulation
http://www.vukcevic.talktalk.net/EarthNV.htm
No doubt these findings advocate that we need to research more on the causes of global warming i.e. is it human or naturally induced?. However, which ever side your bread is buttered with regards to climate change, there are increases in global temperatures and burning fossil fuel is only adding to the problem. The problem is that there is competition amongst the economies of the world, and it is compromising the world of the future generations. I seriously think we need to start acting and as soon as possible to prevent further damage.
The link to the paper isn’t working
what’s 1,000 or 2,000 years when climate models for mars prove CAGW climate models for earth are valid?
18 Oct: MSNBC: Reuters: Deborah Zabarenko: Models of Earth’s climate change confirmed on Mars
Astronomers find that computer calculations match up with traces of ancient snowfall
Astronomers say computer models have accurately forecast conditions on Mars and are valid predictors of climate change on Earth.
These computer programs predicted Martian glaciers and other features on Earth’s planetary neighbor, a U.S.-French team of scientists found.
“Some public figures imply that modeling of global climate change on Earth is ‘junk science,’ but if climate models can explain features observed on other planets, then the models must have at least some validity,” lead researcher William Hartmann of the Planetary Science Institute said Tuesday in a statement.
The team’s findings were presented at the annual meeting of the American Astronomical Society’s planetary sciences division in Reno, Nev…
***”We do have a lot of public figures, in our country particularly, saying that the global climate modeling studies have very little value,” Hartmann said. “If the global climate modeling people can run these models on Mars and we actually see things that come out of the model on another planet, then the climate modeling people must be doing something right.”
http://www.msnbc.msn.com/id/49456341/ns/technology_and_science-space/
Thankfully the Great Climate Wall at the equator prevented these brief regional warming periods from being global events.
The hottest July in the contiguous US (after adjustments) is proof of anthropogenic global warming. A single inconveniently-located hurricane is proof of anthropogenic global warming. But the Northern Hemisphere being far warmer than today cannot be an example of historical global warming greater than today’s global warming, because local cannot be global unless humans are to blame.
The signal is so strong it’s fudge-proof. Another disaster for CAGW. Even lukewarmism, as both those periods were manifestly better for all species concerned, including ours. And CO2 was waaaaayyy lower.
Edit: “the summers of the Roman Warm Period of 2000 years ago was ” //were//
Link to .pdf of full paper doesn’t work.
Kurt in Switzerland
The Romans produced red wine from locally grown grapes north of York, UK. A similar grape now grows south of Dijon in France over 350 miles south of York. So warmer back then.
If you follow the H/T to Tory Aardvark, the link from there works fine, it’s here:
http://www.wsl.ch/fe/landschaftsdynamik/dendroclimatology/Publikationen/Esper_etal.2012_GPC
working link to paper to be found on Esper’s homepage
I remain skeptical that it’s possible to tease a sensible “temperature signal” out of tree rings at all, and the large error span (see dashed lines) support my position. However, it’s so refreshing to read “We conclude that the temperature history of the last millennium is much less understood than often suggested, and that the regional and particularly the hemispheric scale pre-1400 temperature variance is largely unknown.” Applause!
Uchiha says:
October 18, 2012 at 1:35 am
No doubt these findings advocate that we need to research more on the causes of global warming i.e. is it human or naturally induced?. However, which ever side your bread is buttered with regards to climate change, there are increases in global temperatures and burning fossil fuel is only adding to the problem. The problem is that there is competition amongst the economies of the world, and it is compromising the world of the future generations. I seriously think we need to start acting and as soon as possible to prevent further damage.
Are you implying that we need to stop competing in the world economy? Why wait for AGW? Let’s just commit suicide now and get it over with!
Here’s the link
http://www.geo.uni-mainz.de/Dateien/Esper_2012_GPC.pdf
Link for paper:
http://www.geo.uni-mainz.de/Dateien/Esper_2012_GPC.pdf
Earth has gone through cycles of cooling and warming throughout its history but this does not imply that what we are experiencing the same situation. The increase of CO2 in the atmosphere is a fact and studies show that this increase represents the best fit to the increase in temperatures as it correspond in terms of trend and magnitude. Prediction for climate changes in the next 30 years are quite accurate and the intensifying of events as storms and drought should encourage not only further studies but also adaptation measures as, even if naturally caused, climate changes are going to affect food production, water availability etc. Moreover fossil fuels production is not sustainable anymore since not only pollution levels are increasing and so health is endangered, but also as resources are becoming scarcer and scarcer the price is increasing and so it is becoming not economically feasible to continue this sort of production.
Uchiha:
At October 18, 2012 at 1:35 am you say
Please explain what you think is a “problem” in longer growing seasons and cheap energy.
Richard
I wonder what would happen if Mikes “NATURE TRICK” was applied to the graph????
Linkto PDF: http://www.wsl.ch/fe/landschaftsdynamik/dendroclimatology/Publikationen/Esper_etal.2012_GPC
Uchiha (01:35 am) writes “there are increases in global temperatures and burning fossil fuel is only adding to the problem”
If you had written “temperature are varying entierely within the historical range, and there is no problem” I’d have agreed with you.
This article puts and interesting spin on our current fixation with human induced climate change. If we look back into ‘deep time’ the geological climate is ever changing and highly variable. Even though this article isn’t necessarily representative of global climate change, it points to some very valid and worthwhile ideas regarding climate change over much longer periods of time. What about a million years ago? What kind of change have we experienced over that period? As humans we tend to live in a very self centered, short term reality and it is important to step back and analyse climate change from a longer time period, as this can point to the extent to which we are actually changing the climate and thus the environment. It is inarguable that we have had an effect on the increased temperatures in the past century, but these kinds of papers help us realise that we may not be the climate ‘hell spawn’ that the media likes to imply.
Marcel Terblanche
Cape Town
Memo to people saying the link doesnt work – it might be more helpful to google the paper and post the correct link
http://www.geo.uni-mainz.de/Dateien/Esper_2012_GPC.pdf
Yet another stake through the heart of the CAGW monster , any normal scientific hypothesis would be long dead with this many holes in it but CAGW keeps lurching around making groaning noises and sucking the fiscal life out of the world like some sort of vampire/zombie hybrid . I shouldn`t be be surprised at the similarities though , the post-normal science of CAGW , zombies and vampires have two things in common , they`re all fictional terrors designed to frighten Us and being undead they need to feed on the living , be it brains , blood or economies
Uchiha says:
October 18, 2012 at 1:35 am
“there are increases in global temperatures and burning fossil fuel is only adding to the problem”
—————————————————————————————
Not only did the Romans have better weather, they also had more intelligent superstitions.
Here is the link:
http://www.geo.uni-mainz.de/Dateien/Esper_2012_GPC.pdf
http://www.pannelldiscussions.net/2012/10/226-modelling-versus-science/
Interesting link for WUWT readers. Modeling issues discussed.
The Medieval,Roman and Minoan periods are approximately 1,000 year apart at peak and this MODERN warm period is also around a 1,000 years from the MWP peak.
Who knew chariots produced so much CO2. 😉
Ah, the ending.
“Expert teams are needed to assess existing records, and to reduce uncertainties associated with millennium-length temperature reconstructions, before we can usefully constrain future climate scenarios.”
I have memorized the ending. We get the ending served up morning, noon, and night. If a midnight snack is wanted, you will be served another helping of the ending. This one comes with plating artistry.
If you are a foodie you know what plating means. The only differences between meat, potatoes, and gravy served on a kitchen plate, and meat, potatoes, and gravy plated up is that the former has the gravy spooned over the top of the food, hold the sprig, whereas the latter has the gravy artistically swirled under the food with a sprig of green something stuck somewhere into it.
Regarding this particularly subtle but still necessary-for-funding ending reference to anthropogenic scary climate scenarios, four marks for plating.
The paper seems well researched, and I’m not going to pretend I’m enough of a scientist to dispute it. I do however think that this does not in any way rule out the anthropogenic role in our present day Climate Change. This may be simply another contributing factor, and by all means the IPCC should review this, but it doesn’t mean we can ignore all other factors.
@Brian H. You haven’t really explained why this ‘fudge-proof’ paper is a disaster for CAGW. Nobody claims that climate change is purely anthropogenic, whats so strange of the idea about a natural process taking place alongside our own contributions? As you clearly state, atmospheric CO2 was much lower in the past warming periods, but today it isn’t and we can see this manifesting itself in ocean acidification, a process this paper in no way ‘explains away’, and this is indisputably mans doing.
Finally, warming periods in the past may have been better then, when the world did not have 7 billion mouths to feed and ecosystems were not already on the point of collapse from various other influences. How would we cope with this now? Entire countries can’t simply migrate their agricultural sectors to higher latitudes at will. Natural or not, these are issues that we need to address, not just ignore.
I’ve noticed recently an uptick in canned AGW proponent responses to debate on WUWT. These responses usually have little to do with the particular thread topic they appear in. In terms of debate science, this tactic is considered to be very poor debate form for numerous reasons. My recommendation is to debate the style and/or content of the article or face debate dismissal of your comment due to lack of substance. Humor is always an exception to debate tactics as long as it is light hearted.
And yes, I have violated my own recommendation but am reminded by these canned blurbs how poor my comment must have looked.
Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago was significantly warmer than today.
Should be “were” not “was” in both cases.
R Taylor says: “Not only did the Romans have better weather, they also had more intelligent superstitions.”
I have always thought of CAGW in terms of bad science or cultish beliefs, but the concept of it being a superstition is equally appropriate..
luval:
WUWT really does have a bad troll infestation today.
Your post at October 18, 2012 at 3:02 am says in total
That is so wrong it is astonishing. Every statement in it is plain wrong.
“Earth has gone through cycles of cooling and warming throughout its history but this does not imply that what we are experiencing the same situation.”
It does according to science. Read up on the Null Hypothesis which is a fundamental scientific principle.
“The increase of CO2 in the atmosphere is a fact and studies show that this increase represents the best fit to the increase in temperatures as it correspond in terms of trend and magnitude.”
The increase of CO2 in the atmosphere has no relationship to the increase in temperatures. Indeed, the global temperature stopped rising 16 years ago but the increase to CO2 in the atmosphere has not stopped.
“Prediction for climate changes in the next 30 years are quite accurate”
No! They are completely wrong!
The IPCC AR4 predicted (n.b. predicted and not projected) that global temperature would rise at an average rate of 0.2 deg.C/decade +/-20% over the period from 2000 to 2020. This was “committed warming” which was certain because of GHGs already in the system. And the rise would be double that if emissions continued as they have. To date there has been negligible rise in global temperature since 2000. Therefore, for the minimum temperature rise of this prediction to be true then a rise of 0.64 deg.C must occur over the next nine years. This is extremely implausible: the entire rise over the last century was only about 0.8 deg.C. And if this jump in temperature were to occur then it would not explain where the “committed warming” has been hiding since 2000.
Those are only the first three statements in your post. I could refute the rest of the statements in your post, too. But it is not worth the bother spending time on such bunkum.
Richard
pat says:
October 18, 2012 at 1:49 am
what’s 1,000 or 2,000 years when climate models for mars prove CAGW climate models for earth are valid?
I suspect four major reasons for climate models working better for mars.
1 Cloud cover and oceanic contributions may be easier to model for mars.
2 The number of available proxies may be significantly smaller for mars.
3 Data does not have to be massaged to fit anthropogenic forcing.
4 There may be a much less active group scrutinizing their findings.
Yes but according to the Australian Acaedmy of science the distant geological past has nothing to do with the causes of global warming, (unless of course it shows that temperatures were less than the current warming caused by humans).
Luval
The increase of CO2 in the atmosphere is a fact and studies show that this increase represents the best fit to the increase in temperatures as it correspond in terms of trend and magnitude. Prediction for climate changes in the next 30 years are quite accurate and the intensifying of events as storms and drought should encourage not only further studies
This statement is wholly false, all AR4 models are biased high showing no skill, see
http://tinyurl.com/8lkyj5b
they were tuned to hindcast correctly, as a result their collective projections have failed at 95% confidence or will fail by mid 2013
a 10 year rolling trend analysis arguably suggests an inverse relationship between increasing CO2 and land/ocean temperatures over the past 20 years
http://tinyurl.com/hadcrut4hadsst2co2decadal1990
There are two points made by warmist re the modern warming: 1) that the temps are higher than any (sustained) in the last 1000 or 10,000 years, and 2) that the rate of warming since the mid-60s is “unprecedented”, i.e. greatest in the last etc.
The proxy reconstructions put the lie to both. That is good. The warmists say that yesterday is not pertinent to today because warming may be caused by solar changes yesterday, while they are caused by CO2 today. Based on circular reasoning, but a reasonable starting point. The clincher is the rate of warming, which is tied to the date of fossil-fuel CO2 injection, and (circular reasoning again, considering the assumptions) the “empirical” mathematics of CO2-forcing.
Having warming rates similar in the past to those today makes two coincidences for CAGW theory to deal with. Occam’s Razor puts the doubt it, or should.
If Mann publicly accepts any of these reconstructions, Gore is in trouble. And once Gore is in trouble – as he is the “prophet” of Global Warning, the whole Church is in trouble.
My bet: Mann will brush them off.
Lots of (very polite) comments maintaining that CAGW is still a fact. Are these from the “Crusher Krew”?
luval says:
October 18, 2012 at 3:02 am
Moreover fossil fuels production is not sustainable anymore since not only pollution levels are increasing and so health is endangered, but also as resources are becoming scarcer and scarcer the price is increasing and so it is becoming not economically feasible to continue this sort of production.
=========
actually, in the first world at least, pollution levels are much decreased over what they were 50 or 100 years ago.
what solution do you propose? the earth is currently supporting more people in greater prosperity and health than in any age previously. low cost energy derived from fossil fuel is the driving engine behind this prosperity. to change this, market forces require that you must come up with a lower cost alternative, or you must reduce the prosperity of the people of the earth.
if for example we were to return to burning wood for energy, which was common in the past, the forests of the earth would need to be burned within a decade or two to supply our current energy needs. This can be seen in the US, where many of the forests cut down 200-300 years ago to supply firewood have now regrown.
I personally would like to see an end to burning fossil fuel as an energy source. I would prefer to have a low powered fusion reactor in my house that ran off tap water, so that I didn’t need to send my hard earned money to the power and gas companies each month. However, until the Mr Fusion units go on sale at Walmart and Costco, I’m pretty much stuck.
I would certainly appreciate it if the government would pay me to replace my roof with $100,000 worth of solar panels. My only question is, where is the government going to get this $100,000? If they are giving me $100,000 and my neighbors $100,000, then I suspect they are going to have to raise my taxes by $150,000 to pay for my roof. $50,000 to pay the government officials, who approve my roof, and the $100,000 to pay for my roof.
On that basis I would rather keep the $150,000 in my pocket.
The paper seems well researched and points out some valid points; however the paper appears as though they are against the whole idea that the world’s warming periods have been increasing drasticaly in the 21st century and the scarry part is the after effects of this increase in temperatures in the next decade/century. The increase in these temperatures is partially anthropogenetic and also natural variabilities, but anthropogenetic activities are the main drivers of warming in this 21st century, and that is not a factor that one can be ignorant of. It is inarguable that temperatures indeed have been increasing for past millenium,and no one disputes the fact that some temperature increases where higher than the recent temperature increases, but the focus is how the increase was in the last 2000 years ago, was it is increasing rapidly like it is recently or it was gradually increasing with time?. it is inevitably that today the warming preiod is increasing drastically due to human activities. Borrowing the last statement of the paper that “the temperature history of the last millennium is much less understood than often suggested. Indeed it is less understood, because going back to thise times there were not many stresses affecting the warming of the world, human population at that time was far less than 7billion, and the activities at that time were not as intense as they are today. Hence it is better to start teaching people about adaptation and mitigation and not advice them to be ignorant about this matter that our climate is changing, and that the warming periods are increasing at a high rate.
There is a lot of uncertainty when it comes to projections of future climate, we need to take into consideration that this issue is not only a direct result of human activity; it is also coupled by natural forces and feedback mechanism. The temperatures in the past were once higher than what we claim to be global warming today, what we still don’t know is the rate that the temperature increased by. In this case we don’t know the magnitude of the effect that human activities play in amplifying the effect of increase in temperatures. Whether we like it or not the symptoms of what seems to be global warming are out there and affecting each and every one of us at different scales, social or economic aspects of life.
On that basis I would rather keep the $150,000 in my pocket.
==========
Invested that $150,000 will bring an income of $500+ a month. About what I spend on fossil fuel energy each month. So, if I don’t put up solar panels, my energy is free.
TeddyslayerZA
@Brian H. You haven’t really explained why this ‘fudge-proof’ paper is a disaster for CAGW. Nobody claims that climate change is purely anthropogenic, whats so strange of the idea about a natural process taking place alongside our own contributions? As you clearly state, atmospheric CO2 was much lower in the past warming periods, but today it isn’t and we can see this manifesting itself in ocean acidification, a process this paper in no way ‘explains away’, and this is indisputably mans doing
Sorry to disillusion you, but that is precisely what Warmistas have been saying, that there is no natural variation going on just AGW because of man’s emissions of CO2. We don’t know for certain that there was less CO2 in the atmosphere in the previous warm periods, CO2 dissolves in ice in such a way that losses are incurred, & losses are also incurred in the CO2 extraction process, so in fact they could have been higher. Danish research on fossilized plant stomata from the bottom of prehistoric lakes have shown that over Denmark at least, atmospheric concentrations were at about 320-330ppm some 9500 YBP, therefore it is hightly unlikely that this was just located over Denmark only, & not over much more of Europe (certainly there is currently more over Brussels & Strassbourg at the EU HQ)! The IPCC arbitrarily ignored thousands of well measured levels of atmospheric CO2 taken pre 1958 Mauna Loa measurements that demonstrated variations of Northern Europe of betyween 320-450ppm, many taken before the Industrial Revolution could have had any significant effects from fossil fuel burnng! It has also been noted that due to the way CO2 is dissolved in ice today’s blip of 390ppm would not be seen in core samples in another thousand years time! Taking this into consideration, therefore instead of assuming that CO2 increases were from 270ppm to 390ppm (44%), they could have been 330ppm to 390ppm, (18%) much less than claimed! The warming of today in not unprecedented as claimed, & if you actually look at the ice core records, going back the last few hundred thousand years, they show clearly that temperatures have risen & fallen wit ice-ages, & that when warming the temp plots look rather like a central heating overshoot graph before settling to the desired temperature, on top of which it was warmer 11500 YBP & that the Earth has been cooling off pretty muh ever since, inaccordance withh previous Inter-glacials!
What the AGW proponents are missing in this debate is that the reason they want us to be so frightened is that they believe we are approaching some sort of horrible tipping point in which an irreversible positive feedback loop commences and we are all boiled.
They now should explain why the warmer warming in the past did not lead to a feedback loop, but today’s cooler warming will lead to a feedback loop.
Anybody notice K.R Briffa and tree-rings in the references?
RichardS, Schnurrp, Brent, Pamela…
Today’s trolls (Uval, Uchiha, etc) could very well have been directed here by something like the “Campaign Against Climate Change Aggregator” (which is what I use as a convenient way to make sure I don’t miss anything by Bishop Hill). With that in mind, I kind of enjoy their very silly (mostly) canned responses.
The tone of the paper’s conclusions dovetails with the assertion that we obtain better “absolute” constraints on MWP T from pre-LIA maps that show the Arctic coastline of Eurasia. And yes, AGW would be a good thing if there is such a thing.
Blaming weather catastrophe on Deity has an advantage over blaming CO2 in that it remains possible to reconcile natural cause and effect with divine fiat, while blaming every disaster on CO2 puts the weathermen and their science out of business. –AGF
Characterizing the above pro-CAGW commentors as trolls is an insult to the intelligence of respectable trolls like Lazy Teenager and (the late?) R Gates. Zombies more like. I wonder where they got their feeble boilerplate talking points from? Makes me think of the last days of the Third Reich when the Germans were sending to the collapsing front any male who could functionally differentiate between the two ends of a gun. (If they post intelligent replies to Richard’s counters, consider my comment happily retracted; give it a try or concede, zombies!)
Meanwhiile, enjoy the anticipation of the inevitable collapse of the CAGW “House of Pain”, which might look something like this:
The error bar is +or- 2 degrees C? So tree ring proxies are as accurate as mercury thermometers being eyeballed by individuals of varying height and hence various parallax error? What happened to the glacial lake sediment proxies ? Are none available in Northern Scandinavia?I remain extremely sceptical of the temperature information one can glean from tree rings.
We have been cooling for the past 65 million years. A little warming would be beneficial. http://joannenova.com.au/2010/02/the-big-picture-65-million-years-of-temperature-swings/
ferd berple says:
October 18, 2012 at 8:00 am
“On that basis I would rather keep the $150,000 in my pocket.
==========
Invested that $150,000 will bring an income of $500+ a month. About what I spend on fossil fuel energy each month. So, if I don’t put up solar panels, my energy is free.”
I just want to know where you can get that good of a return. Las Vegas or Wall Street? But then they are about the same. Never mind.
I’m just pleased to see such papers getting published. At least this adds to the topic of AGW getting further scientific discussion instead of just being continually presented as “an ironclad truth”.
I’m still surprised by those coming in here and saying (paraphrased) “Thats all well and good, it may have been warmer then, but it is an inescapable fact that the reason we have warming now is because of anthropogenic release of CO2… And this can be proven by the fact there are more people around now.” ( Zinzi:October 18, 2012 at 7:51 am)
Bit of a lapse in logic right there.
TeddySlayerZA says:
October 18, 2012 at 6:22 am
“Entire countries can’t simply migrate their agricultural sectors to higher latitudes at will. ”
==========================================================================
Of course they can and do and did, as during the MWP. But of course the US wheat belt labors under the opposite trend of a decreasing temperature, however minor. If this trend ever reversed, Canadian grain growers would be happy to make up the difference.
Everything you believe is nonsense. –AGF
Unfortunate equivocation over:
Summer vs. annual temps;
Regional vs. global temps;
Mid-20th Century temps vs. “today” (60 years & 0.6C or so difference).
Zinzi:
In your post at October 18, 2012 at 7:51 am you begins saying
There has been NO global warming in the 21st century. All the available data sets (HadCRUT, GISS, GHCN, RSS, UAH) show no global warming for the last 16 years.
And you keep talking about “anthropogenetic”. Once could be a misprint, but more than once?
So what does “anthropogenetic” mean?
Richard
nominki:
At October 18, 2012 at 7:52 am you assert
Bollocks!
Whether you like it or not, there is no evidence of man-made global warming; none, zilch, nada.
And there is much evidence that refutes the hypothesis of anthropogenic global warming (AGW); e.g.
Trenberth’s “missing heat” is not down the back of my sofa nor anywhere else anybody has looked
Global temperature has not risen over the last 16 years while GHG emissions continue to riseThe ‘hot spot’ is missing.
Accelerated polar cooling is not happening in Antarctica
The “committed warming” has vanished
etc.
Richard
I don’t mind the troll’s showing up here. I am willing to bet that most of the Skeptics that frequent this blog at one time were a believer of CAGW to one degree or another. If Muller can become a believer then a troll can become a Skeptic! Seriously these guys have to start seeing a pattern if they have any common sense at all. But then again it could just be they are somehow on the climate money train and are fearful of the train coming to an assured abrupt stop.
There is a lot baloney written about CO2 effect on the temperatures since 1880s. The CO2 concentration is affected by temperature, and temperature to some degree may or may not be affected by CO2.
However there are variables which can affect temperature change, but reverse is not possible. Here is an example:
http://www.vukcevic.talktalk.net/NAP-SST.htm
Most geologists are familiar with the data marked ‘N. Atlantic precursor’, which here it is shown in integrated form. Not much room left for the anthropogenic.
@richardscourtney
Actually, the Null Hypothesis is a creature of statistics, not science. It comes into play in science only because so much of modern science is dependent on statistical testing.
RobW said:
“Who knew chariots produced so much CO2. ;)”
-Chariots of Fire 🙂
richardscourtney says:
October 18, 2012 at 10:15 am
Replying to Zinzi:
[in part]
“And you keep talking about “anthropogenetic”. Once could be a misprint, but more than once?
So what does “anthropogenetic” mean?”
================================================================
I didn’t check Wikipedia, but I think it’s a mutation of anthropomorphic, neither of which is sustainable at current high levels of carbon ;o)
Ya got me chuckling after those great catches, Richard. Thanks.
Matt:
At October 18, 2012 at 11:31 am you say to me
That is so wrong it is gobsmacking!
Where did you get such a wrong idea; some anti-science warmist web site such as SkS?
The Null Hypothesis says it must be assumed a system has not experienced a change unless there is evidence of a change.
The Null Hypothesis is a fundamental scientific principle and forms the basis of all scientific understanding, investigation and interpretation. Indeed, it is the basic principle of experimental procedure where an input to a system is altered to discern a change: if the system is not observed to respond to the alteration then it has to be assumed the system did not respond to the alteration.
In the case of climate science there is a hypothesis that increased greenhouse gases (GHGs, notably CO2) in the air will increase global temperature. There are good reasons to suppose this hypothesis may be true, but the Null Hypothesis says it must be assumed the GHG changes have no effect unless and until increased GHGs are observed to increase global temperature. That is what the scientific method decrees. It does not matter how certain some people may be that the hypothesis is right because observation of reality (i.e. empiricism) trumps all opinions.
Please note that the Null Hypothesis is a hypothesis which exists to be refuted by empirical observation. It is a rejection of the scientific method to assert that one can “choose” any subjective Null Hypothesis one likes. There is only one Null Hypothesis: i.e. it has to be assumed a system has not changed unless it is observed that the system has changed.
In the case of global climate no unprecedented climate behaviours are observed so the Null Hypothesis decrees that the climate system has not changed.
Importantly, an effect may be real but not overcome the Null Hypothesis because it is too trivial for the effect to be observable. Human activities have some effect on global temperature for several reasons. An example of an anthropogenic effect on global temperature is the urban heat island (UHI). Cities are warmer than the land around them, so cities cause some warming. But the temperature rise from cities is too small to be detected when averaged over the entire surface of the planet, although this global warming from cities can be estimated by measuring the warming of all cities and their areas.
Clearly, the Null Hypothesis decrees that UHI is not affecting global temperature although there are good reasons to think UHI has some effect. Similarly, it is very probable that AGW from GHG emissions are too trivial to have observable effects.
The feedbacks in the climate system are negative and, therefore, any effect of increased CO2 will be probably too small to discern because natural climate sensitivity is much, much larger. This concurs with the empirically determined values of low climate sensitivity.
Empirical – n.b. not model-derived – determinations indicate climate sensitivity is less than 1.0deg.C for a doubling of atmospheric CO2 equivalent. This is indicated by the studies of Idso from surface measurements
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
and Lindzen & Choi from ERBE satelite data
http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf
and Gregory from balloon radiosonde data
http://www.friendsofscience.org/assets/documents/OLR&NGF_June2011.pdf
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf
Indeed, because climate sensitivity is less than 1.0 deg.C for a doubling of CO2 equivalent, it is physically impossible for the man-made global warming to be large enough to be detected (just as the global warming from UHI is too small to be detected). If something exists but is too small to be detected then it only has an abstract existence; it does not have a discernible existence that has effects (observation of the effects would be its detection).
To date there are no discernible effects of AGW. Hence, the Null Hypothesis decrees that AGW does not affect global climate to a discernible degree. That is the ONLY scientific conclusion possible at present.
Richard
In human terms warm seems to mean wealth and extended lifespans and better health. Cold seems to correlate to death, starvation ,disease and the backsliding of culture and knowledge. So maybe warm means good and cold means bad in human terms?
It’s true that in history, warmer summers have generally been embraced as beneficial to agriculture etc., but that is probably a perspective which comes largely from northern temperate climates. The very hot summer combined with drought conditions over much of the US hasn’t been keenly welcomed, especially by farmers. With the current very rapid anthropogenic warming there are bound to be winners as well as losers, and perhaps Northern Europe will enjoy the longer growing season for a while – provided it’s not accompanied by drought. However, given that we’re pumping out greenhouse gases faster than ever, and AGW looks set to continue for many decades at least, the losers are going to greatly outnumber the winners overall. We will of course adapt and cope to some extent but there is inevitably going to be a huge financial and human cost.
Icarus62:
At October 18, 2012 at 12:48 pm you write in total
Meanwhile, here on planet Earth global warming stopped 16 years ago. There is NO “current very rapid anthropogenic warming”. In fact there is no global warming and recent very slight cooling.
Of course, this situation of flat-lining global temperature will end. Either warming will resume towards the temperatures of the Medieval Warm Period (MWP) or cooling will set in towards the temperatures of the Little Ice Age (LIA).
Hope for warming because it benefits almost everybody but cooling harms everybody. And there is nothing we can do to avoid whichever happens.
Richard
Icarus62 says:
October 18, 2012 at 12:48 pm
“…the losers are going to greatly outnumber the winners overall.”
===========================================================
Or so goes the dogma, but is there any science behind it?
1) Low latitude is more water; high latitude is more land; hence, more agriculture.
2) Hotter means more evaporation and more rain, hence more agriculture.
3) This matters little: CO2 IR measures 1-2 W/m^2; insolation varies 100W/m^2 TOA at temperate latitudes and barely manages to end an ice age. Everything you believe is a fairy tale. –AGF
Richard: We know that anthropogenic global warming is accelerating, as are many of its consequences such as disappearing Arctic sea ice and melting glaciers and ice caps worldwide, validating many decades of predictions by climate scientists. The big question is not so much whether this rapid warming will continue – that’s inevitable barring an immediate and enormous rise in volcanism – but what the impacts are going to be and how we will cope with them. We cannot expect human civilisation to suddenly give up fossil fuel use without massive loss of life, so the big money needs to go on adaption to the growing climate chaos, disaster management, population control and so on.
[my bold]
REPLY:
Can I take a ride on your time machine?
http://wattsupwiththat.com/2012/05/27/another-paper-shows-that-severe-weatherextreme-weather-has-no-trend-related-to-global-warming/
http://hockeyschtick.blogspot.com/2012/09/new-paper-shows-warming-causes.html
I hope Steve at Climate Audit takes a look at this. In the end it is another “treemometer” effort, so I’d like his take on what was done with the data.
TeddySlayerZA says:
Nobody claims that climate change is purely anthropogenic,
Teddy, there are people out there who state that over 100% of the warming is due to AGW! That is they believe that if it were not for CO2, that we would be cooling. So you are wrong. There are people who effectively attribute all recent climate change to “greenhouse” gasses.
In the world of extreme warming phobia, nothing is too stupid to be believed.
If you believe that the world has recently been as warm as it is now – as this paper suggests – you find it hard to believe we are in a crisis. Which is why the most alarmist scientists try desperately to get rid of the Medieval Warm Period. They know that it is, easily, the strongest argument against the CO2 theory.
agfosterjr: If the climate is as insensitive to forcings as you suggest then why do ‘skeptics’ like to suggest that a few tenths of a Watt reduction in insolation will plunge us into a new mini ice age?
icarus62:
Your post at October 18, 2012 at 1:53 pm is such a total load of baloney that I copy all of it to ensure that nobody thinks I am addressing anything out of context. It says to me
We do NOT “know that anthropogenic global warming is accelerating”. Indeed, nobody has managed to detect any AGW let alone measure its rate.
There are NO observed effects of anthropogenic global warming (AGW) “accelerating”. The recent reduction in Arctic ice certainly is NOT an indication of AGW “accelerating”. Indeed, polar caps are NOT “reducing worldwide”. Antarctic ice is growing and very recently achieved a record amount. If Arctic ice decline is evidence that AGW is “accelerating” then the growth in Antarctic ice to its recent record level is evidence that AGW is NOT happening.
The changes to glaciers et al. only indicate that the Earth has been recovering from the Little Ice Age (LIA) back towards the temperatures of the Medieval Warm Period (MWP). The glaciers started to recede centuries prior to any significant AGW.
Global warming cannot “continue” because it stopped 16 years ago. Indeed, very recently there has been global cooling. At issue is whether the present flat-line of global temperature will end with resumption of warming towards the temperatures of the MWP or is a transition to cooling towards temperatures of the LIA. I suggest you pray for the benefits of warming and not the horrors of cooling because prayer is the only thing we can do to affect either.
Importantly, all your suggested activities are outrageous and horrific. For example, if you think “population control” is desirable then there is only one way you can reduce the size of the population without harming others and that would only reduce it by one. Perhaps you will work out what it is and do what you say is required.
Richard
Best I can tell from the responses here, the party line is, in essence: “It’s different this time”
icarus62 says:
“We know that anthropogenic global warming is accelerating, as are many of its consequences such as disappearing Arctic sea ice and melting glaciers and ice caps worldwide, validating many decades of predictions by climate scientists.”
So many false statements in just one sentence.
Luval wrote: “Prediction for climate changes in the next 30 years are quite accurate . . .”
You must be a wizard. I don’t know why we even bother to have models if you have magical powers that let you see the future, Why don’t you be the climate king and just tell us what to do.
Seems to be desperation from the warmistas, judging from the mount of new trolls pouring in with the usual inane comments. The missing heat seems to have been discovered. It’s all turning up at the warmistas. Feeling the heat, losers?
richardscourtney says:
October 18, 2012 at 12:11 pm
The Null Hypothesis says it must be assumed a system has not experienced a change unless there is evidence of a change.
The Null Hypothesis is a fundamental scientific principle and forms the basis of all scientific understanding, investigation and interpretation. Indeed, it is the basic principle of experimental procedure where an input to a system is altered to discern a change: if the system is not observed to respond to the alteration then it has to be assumed the system did not respond to the alteration.
It was Charles Darwin who said that doing science without a hypothesis is like going to a gravel pit and counting the stones in it. I think the principle extends to the null hypothesis also – for every hypothesis there is the reciprocal null hypothesis. A “hypothesis” is in a sense an epiphenomenon, the counter null hypothesis actually has more reality and substance. A “hypothesis” is established by refuting the corresponding null hypothesis.
The null hypothesis flows directly from Karl Popper’s assertion that science can only be deductive, not inductive. Popper states this in a way that sounds extreme and dogmatic (“there are no inductive inferences, any that appear to be so are illusory”) but the logic he develops around this seems unassailable. You cannot prove a hypothesis, but you can disprove a null hypothesis.
(See “Conjectures and Refutations” by Popper.)
Esper et al. – YET ANOTHER paper that shows the overwhelming ordinariness of our recent climate history of the last century or two.
icarus62 says:
October 18, 2012 at 1:53 pm
so the big money needs to go on adaption to the growing climate chaos, disaster management, population control and so on.
And there you have the money quotes from the Warmistas. I especially like the population control one.Stalin,Mao,Pol Pot,etc would be so proud.
mods….anyway to track just where all these canned eco-cultists are showing up from?
Holy Roman Empire.
Jan Esper continues to do some of the best Paleo work I’ve seen.
Seems that Icarus has forgotten, (again) the advice he was given by his father. The wax must be softening quickly…
I do not see how demonstrating that in the northern Scandinavia ,summer temperatures 1000 years or 2000 years ago were warmer than Scandinavia’s current warmest summer ‘links’ to Global warming (Or cooling for that matter) as this article is supposedly suggesting. There had always been variations. Indeed there are millenia that were warmer than today but this does not necessarily mean that our current warming situation (If we all agree there is warming after all) is totally natural and nothing of concern. To the comments that are questioning the validity, representiveness and accuracy of this data from tree trunks, I say even though IPCC might not take this warnings as an alarm, truth almost always come from the corners least expected and therefore we must treat every data with equal caution and consideration. A cold millenium or two ( little Ice age or current era) after a warmer one ( Roman era) suggests nothing about Global warming. We need to do a lot of maths and look at trends, general trends not mere variation.
Just because there were warmer summers in the past doesn’t mean it’s OK to have warmer summers now. 1000 and 2000 years ago if there was increased flooding in rural areas, less people would have been affected. In the Roman era, the population was estimated to be 200 million (source). We are currently over 7 Billion… that means there are 35 times more people, taking up 35 times more space, with an even larger than 35 times bigger carbon footprint. During the Roman era, it can be argued that the warming was part of a natural cycle, but one cannot argue now that our massive increase in GHG emissions is causing the global temperature to rise, which will result in more extreme weather events, and as there are now more people, more people will be negatively affected, and in turn it will affect everyone, whether you’re safe in your home in Switzerland or living in a shack in India.
Sources:
http://www.vaughns-1-pagers.com/history/world-population-growth.htm
Interesting historical parallel with the history of the Roman Empire, which reached its peak around the first century AD and fell apart completely in the fifth.
Of course, I am not suggesting that climate drove the entire history of the Empire. But, it was largely agrarian-based economically. If the seasons got progressively colder, yields would have fallen. Nothing like a bit of hunger among the peasantry to undermine support for the rulers.
phlogiston:
At October 18, 2012 at 9:10 pm, in response to my explanation of the Null Hypothesis at October 18, 2012 at 12:11 pm, you conclude saying
Yes. That is why my explanation says
Of course, and as you say, one needs to decide the observation which would indicate the system under study has changed. And my explanation includes that for consideration of AGW saying
Richard
Muzi:
Your muddled and illogical post at October 19, 2012 at 1:12 am concludes saying
Maths done. Trends analysed.
There has been NO global warming for the last 16 years and a very slight cooling trend over very recent years. Global warming is “an ex-parrot”.
Next false scare please.
Richard
Matt:
Your post at October 19, 2012 at 2:10 am is an outrageous call for genocide on an unprecedented scale. I quote it all because it is so extreme that people reading a rebuttal of it could think the rebuttal exaggerates.
Firstly there is no evidence – none, zilch, not any – that anthropogenic GHG emissions are causing any global warming and much evidence refutes it; e.g.
Missing ‘Hot Spot’
Missing ‘Trenberth heat’
Missing ‘committed warming’
No warming for the last 16 years while the emissions have continued to increase
etc..
And the anthropogenic GHG emissions are NOT “massive increase in GHG emissions”. Nature emits 34 molecules of CO2 for every molecule emitted by all human activities.
Also, “35 times more people, taking up 35 times more space, with an even larger than 35 times bigger carbon footprint” is all trivial on a global scale. Humans inhabit a small part of the fifth of the world which is not covered in water.
But, as you say, “one cannot argue now that our massive increase in GHG emissions is causing the global temperature to rise, which will result in more extreme weather events,”. One cannot argue it because it all baloney.
(a) anthropogenic GHG emissions are NOT causing the global temperature to rise: it has not risen for the last 16 years
and
(b) there is reason to think that if global temperature were to rise then that would REDUCE both the frequency and severity of extreme weather events because it would reduce the temperature differences which cause weather events.
Importantly, reducing “our carbon footprint” would be the greatest crime against humanity which is imaginable. It would probably be worse than thermonuclear war.
People die when starved of adequate energy supply because all human activity requires adequate energy supply for
1. production of food,
2. manufacture of goods,
3.provision of services,
4. heating and cooling,
5. cooking, and
6. transport of food, goods and services from where they are produced to where they are needed.
At present adequate energy supply is provided by fossil fuels and nuclear power. The power available from wind, solar and muscles was abandoned when the greater energy intensity in fossil fuels became available by use of the steam engine. The greater availability of energy enabled more people to survive so human population growth dramatically accelerated.
Human population is now conservatively estimated to be 6.6 billion and continues to grow. The population is estimated to peak around the middle of this century when it will be at least 8 billion.
That additional 2.4 billion people requires additional energy supply to survive. And the only possible sources of the needed additional energy are fossil fuels and nuclear power. A return to wind, solar, animal power and slavery cannot provide anywhere near enough energy.
Most of the needed additional energy must be from fossil fuels because not everything can be powered from the end of a wire. And the use of fossil fuels increases GHG emissions with resulting increase to “our carbon footprint”.
So, holding our “carbon footprint” at its present level would kill at least 2.4 billion people, mostly children, in the next few decades. And reducing our “carbon footprint” would kill more millions or billions.
In other words, on the basis of falsehoods which you assert you are advocating an atrocity which would make relatively trivial the combined activities of Gengis Khan, H1tler, Stalin and Pol Pot.
As someone much wiser than me once said, I say to you, “Get thee behind me, Satan”.
Richard
johanna:
re your post at October 19, 2012 at 2:17 am.
Learn some history before posting such bollocks.
Richard
Any increase or decrease in observed global temperatures are a very likely and inherent part of the climate system given the multitude of external (e.g. solar flares) and internal (e.g. volcanic eruptions) climate forcing factors that influence such temperatures.
What has changed is the growth of the human population and the extent of our influence in the atmosphere that surrounds and, together with the geosphere and hydrosphere, supports human life. Therefore any change in say internal forcing factors, such as the undeniable increase in greenhouse gases, will illicit a response on proportions that weren’t previously measurable i.e. across geographic space largely because these changes affect A LOT more of the population.
Our capacity to adapt to changing patterns can only go so far and like other species with which we share our complex planet a change in habitable space (our distribution) will be affected.
Let’s not forget the spread of the ranges of species that would occur given an increase in temperatures reported by the bodies such as the IPCC. The range of malarial-vector mosquitoes is closely linked to temperature distributions, as this increases so will the spread of malaria areas affecting more and more people throughout the globe.
We have it in our capacity to acknowledge and take measures against the very real threat of a changing climate, be that warming or cooling. The evidence available today certainly shows a general warming trend and the increased occurence of extreme weather certainly warrants adaptive attention.
Perhaps it is time to adopt the PRECAUTIONARY PRINCIPLE wholeheartedly for the benefit of all mankind. After all, the cost of ignoring the issues far out way any (if there are any) negative implications of taking long-term sustainable measures to mitigate and adapt to changes in the climate system.
Richard: The latest 16-year warming trend is 0.12°C per decade according to GISTEMP. Here are some other recent 16-year trends in GISTEMP:
1982 to 1998: 0.15°C per decade
1983 to 1999: 0.18°C per decade
1984 to 2000: 0.19°C per decade
1985 to 2001: 0.17°C per decade
1986 to 2002: 0.16°C per decade
1987 to 2003: 0.17°C per decade
1988 to 2004: 0.20°C per decade
1989 to 2005: 0.21°C per decade
1990 to 2006: 0.23°C per decade
1991 to 2007: 0.26°C per decade
1992 to 2008: 0.28°C per decade
1993 to 2009: 0.21°C per decade
1994 to 2010: 0.17°C per decade
1995 to 2011: 0.14°C per decade
1996 to 2012: 0.12°C per decade
Over the whole period of 30 years, the warming trend is 0.17°C per decade, but 16-year trends range from 0.12 to 0.28°C per decade (average 0.19°C per decade) – there is simply too much short-term variability to claim that a 16-year trend of 0.12°C per decade represents a genuine reduction in global warming. If the 30-year trends started to show a significant decline, then we could agree that global warming was slowing down, but that hasn’t happened.
As Feynman said, the easiest person to fool is yourself – don’t get bogged down in short-term climate variability, and miss the wood for the trees (so to speak).
The geological record reveals great fluctuation in Earth’s climate throughout time. One must keep in mind however that just because the climate alters due to natural means (solar variability, volcanism and changes in the oceans conveyor belt for example) it does not in any way diminish the pressing impact of anthropogenic influenced climate change. It is clear that scientists have not fully understood the magnitude of man made influences vs natural influences on climate, but it is clear that we indeed influence climate. While how much we influence future climate is up for debate, it becomes an ethical debate as to whether a bit of uncertainty is enough for inaction. Regardless of the degree of influence we have on future climate, the fact that we do indeed change the climate should be enough to set forth mitigation policies. A better understanding of past climate such as is put forth by this paper will only help scientists differntiate man made vs natural forcings as well as to help better predict future climate.
Definition of ‘Null Hypothesis’
A type of hypothesis used in statistics that proposes that no statistical significance exists in a set of given observations. The null hypothesis attempts to show that no variation exists between variables, or that a single variable is no different than zero. It is presumed to be true until statistical evidence nullifies it for an alternative hypothesis.
Investopedia explains ‘Null Hypothesis’
The null hypothesis assumes that any kind of difference or significance you see in a set of data is due to chance.
For example, Chuck sees that his investment strategy produces higher average returns than simply buying and holding a stock. The null hypothesis claims that there is no difference between the two average returns, and Chuck has to believe this until he proves otherwise. Refuting the null hypothesis would require showing statistical significance, which can be found using a variety of tests. If Chuck conducts one of these tests and proves that the difference between his returns and the buy-and-hold returns is significant, he can then refute the null hypothesis.
Read more: http://www.investopedia.com/terms/n/null_hypothesis.asp#ixzz29kRpofpP
Null Hypothesis: Null Hypothesis is one of the confusing terms that most students really struggle with, so get comfy, grab a cup of coffee, and we’ll get through it together….
The simplistic definition is that the null hypothesis is the opposite of the hypothesis being tested. The researcher suspects the hypothesis to be true (and thus is doing research to support the hypothesis), but the null hypothesis is the hypothesis the researcher tries to disprove. The researcher never proves or accepts the null hypothesis, but can only reject it or not reject it. Confused? How about an example?
Hypothesis: Roses exhibit greater rate of growth when planted in soil rather than compost.
Null Hypothesis: Roses do not exhibit greater rate of growth when planted in soil rather than compost.
Ok, these are lame, but they make the point. Let’s say the researcher collects and analyzes the data, and the results are statistically significant at the 99% level (the data show that roses do grow better in soil with 99% confidence) – in this case, the researcher would reject the null hypothesis and accept the hypothesis.
Read more: http://www.alleydog.com/glossary/definition.php?term=Null%20Hypothesis#ixzz29kTmKvZq
Matt says:
Just because there were warmer summers in the past doesn’t mean it’s OK to have warmer summers now.
The problem is, if it was warmer in the past, then we are well within the limits of natural variability. If you think warmer summers aren’t OK, and the warming is completely natural, what can we possibly do about it?
Oh, that’s right – this time it’s different.
Johanna
There was a lot of infighting in the Western Roman Empire and they left themselves weak and open to attack from outsiders and so called allies. The Eastern Romam Empire at the other end of the Mediterranean contnued sucessfully for another 1000 years.
We are fortunate to have their climate references and can indeed see considerable fluctuations in climate and the means with which they coped with it
tonyb
TeddySlayerZA says:
I do however think that this does not in any way rule out the anthropogenic role in our present day Climate Change.
Of course it doesn’t. The only way for that to be possible would be if there existed a falsifyable theory of climate that asserted and testably quantified the alleged anthropogenic role in our present day climate change. There ain’t. This is by design.
Nobody claims that climate change is purely anthropogenic, …
Really?
“Our results show that the average temperature of the earth’s land has risen by two and a half degrees Fahrenheit over the past 250 years, including an increase of one and a half degrees over the most recent 50 years. Moreover, it appears likely that essentially all of this increase results from the human emission of greenhouse gases.” – Richard Muller, “climate scientist”.
Finally, warming periods in the past may have been better then, when the world did not have 7 billion mouths to feed and ecosystems were not already on the point of collapse from various other influences. How would we cope with this now?
Better than the Romans. Among the benefits we enjoy that the Romans did not: a CO2 enriched atmosphere, which greatly increases primary productivity in both ecosystems and agriculture. Also – fossil fuel powered agriculture and transport of agricutural products. As I type this, I am sitting at high latitude, eating a fresh orange, while looking out the window at fresh snow.
Entire countries can’t simply migrate their agricultural sectors to higher latitudes at will.
In point of fact, many countries currently have trouble preventing their agricultural sectors from migrating. Japan has a hell of a time keeping its rice production from moving to Alabama, for example.
Of course, the salient point is that there wouldn’t be any need to move many countries agricultural sectors. They would modify and extend it as the prodcutive zone expands due to the warmer temps, the greater atmospheric mosture, and the plant food enhanced air. It may cut down the amount of truck time that an orange endures before it gets to me. Allegedly, that would be good for the environment. Wouldn’t that be wonderful?
Natural or not, these are issues that we need to address, not just ignore.
Natural or not may be a distinction that you can discount. Imaginary or not is still a valid consideration. Scary stories aren’t issues unless they actually happen.
Moderators;
My post to David Spurgeon has come out with reversed formatting. This is a repost that hopefully corrects it. Sorry.
Richard
_______________________
David Spurgeon:
At October 19, 2012 at 5:44 am you report
and say
That is the same as the definition I provided except that it uses confusing statistical-speak.
In my post at October 18, 2012 at 12:11 pm I wrote
Then at October 19, 2012 at 5:48 am you claim
No. It is not “confusing” in any way.
For example, if the hypothesis is
“A lion will react if poked in the eye”
then the Null Hypothesis is
‘There is no discernible reaction from the lion when it is poked in the eye’.
So, poke the lion’s eye and you either get a falsification of the Null Hypothesis or not.
However, there may be difficulty in determining a reaction to an effect. For example, a system may provide variable time series data, and it may be difficult to discern a change to the data in response to an input to the system. Statistical analysis may – or may not – discern a change to the data which is a ‘signal’ that the system changed. But whether or not such statistical analysis is useful and/or complicated does not make the Null Hypothesis “confusing”.
Richard
TonyG says:
October 19, 2012 at 5:52 am (Edit)
Matt says:
Just because there were warmer summers in the past doesn’t mean it’s OK to have warmer summers now.
The problem is, if it was warmer in the past, then we are well within the limits of natural variability. If you think warmer summers aren’t OK, and the warming is completely natural, what can we possibly do about it?
##############################
1. The “limits” of natural variability are huge. Its a vacuous null. The true limits of natural variability of the earth lie between absolute zero and that temperature that will be achieved when our sun explodes. Huge limits. The “natural variation Null” is void and meaningless and un testable.
2. We are very close to temperatures that mankind as a species has never seen before. This is important because we have adapted to the climate our species has experienced. It governs where we live and how we live. Transgressing this historical boundary has unknown consequences. Anyone who wants to argue that it will be better or worse had better bring their
“A” game. I see no one on either side of this debate bring their “A” game when it comes to proving that it will be better or worse. What we know, is that we will be facing something our species has not faced before.
3. The issue is not what we have dealt with in the past. Our best science says we are headed into uncharted territory– for our species. That’s not something one should do without thinking first. Simply, continuing to dump carbon into the atmosphere may not be the brightest thing we have done. Open minded people would put all options on the table.
We are very close to temperatures that mankind as a species has never seen before. ~ stevie
I am guessing, stevie, that you missed the entire point of this article, and the research it speaks about?
richardscourtney says:
No. It is not “confusing” in any way.
It is still slightly confusing to me, Richard. I simply posted some observations from other people, which mentioned the statistical element, rather than the necessarily scientific one. Sorry that in my gross ignorance I annoyed you. 🙂
Steven Mosher:
At October 19, 2012 at 11:38 am you say
Oh dear! That displays such a gulf between your understanding and reality that it discredits everything you say about the subject.
In reality global temperature cannot have moved beyond the true limits of natural variability of the Earth in the Holocene unless global temperature goes beyond the previous maximum or minimum global temperature which has existed in the Holocene.
Richard
richardscourtney says:
October 19, 2012 at 4:20 am
johanna:
re your post at October 19, 2012 at 2:17 am.
Learn some history before posting such bollocks.
Richard
————————————————
Why do you have to be so abusive? I like WUWT because it fosters courteous discussion. This comment is just a nasty drive-by.
FYI, I studied ancient history for several years, read Latin and suggest that I have forgotten more about the Roman Empire than you will ever know.
My comment was semi-frivolous, but there was a serious point in there. As a student of modern, as well as ancient, history, there are plenty of instances of climate related political instability on a regional basis, caused by food shortages in agrarian economies. Severe and lengthy drought and cooling trends are examples of climate phenomena which can devastate agrarian economies with concomitant political effects. It’s not difficult to understand.
It’s much less of a problem today because of fossil fuel driven transportation and refrigeration.
The causes of the decline of the Roman Empire have engaged people in vigorous argument for hundreds of years. I never suggested climate as a single, or even primary cause. I just noted that if it got progressively cooler, there would most likely have been impacts on political stability.
Manners, please!
The warms crawl in, the warms crawl out . . .
“Who’s ‘We,’ white man?”
(Says the rest of the world.)
Steven Mosher says:
“1. The ‘limits’ of natural variability are huge. Its a vacuous null. The true limits of natural variability of the earth lie between absolute zero and that temperature that will be achieved when our sun explodes. Huge limits. The ‘natural variation Null’ is void and meaningless and un testable.”
Response to #1: Throughout the discussion ‘natural variability’ is understood to mean the parameters of the Holocene, not absolute zero or the sun exploding.
“2. We are very close to temperatures that mankind as a species has never seen before…”
Response to #2: Not true. How many charts would you like?☺ In fact, the past 150 years has been a true “Goldilocks” climate, with a temperature variability of ≤ 0.8ºC. That is extremely stable compared to most times during the Holocene.
“3. The issue is not what we have dealt with in the past. Our best science says we are headed into uncharted territory– for our species. That’s not something one should do without thinking first. Simply, continuing to dump carbon into the atmosphere may not be the brightest thing we have done. Open minded people would put all options on the table.”
Response to #3: You ended your comment with the classic Precautionary Principle. But what you actually show is that putting more CO2 into the atmosphere has not caused any global harm at all. In fact, it is very beneficial to the biosphere — which includes us. You have shown that the net result of more CO2 is entirely beneficial. And don’t worry about “carbon” threatening “our species”. There are plenty of credible threats. But CO2 is not one of them.
Hey, Mosher,,
DON’T PANIC !!
Stop being a climate hypochondriac !!!
Steven Mosher says:
2. We are very close to temperatures that mankind as a species has never seen before.
Another one of those ‘A Game’ assertions, though for some reason you dont’ identify it as such.
But accept it for the sake of argument. The rest of that argument implicitly asserts that the current climate is optimum and explicitly asserts that it must be maintained status quo at whatever cost. You don’t hear anybody screaming that where we are now is unbearable, and we should do anything we can to knock off a couple of °C to get back to the good old days. In fact, the current scare was preceded by one based on the assertion that such a circumstance was in the offing, and we should do whatever we could to prepare for the icy doom that was about to befall us. We are therefore not teetering at any precipice. We are centered firmly in the buffer zone.
3. The issue is not what we have dealt with in the past. Our best science says we are headed into uncharted territory– for our species.
Have ya read the post? It says we are heading into territory successfully navigated by people whose high speed transit, primary food source and object of worship were all the same animal.
That’s not something one should do without thinking first.
People who were 99.9% illiterate and 100% superstitious thrived during the previous warm periods. We will be fine.
Simply, continuing to dump carbon into the atmosphere may not be the brightest thing we have done.
Simply, turning our backs on the world’s primary energy source would be the dumbest thing we have done.
icarus62 says:
October 18, 2012 at 2:59 pm
agfosterjr: If the climate is as insensitive to forcings as you suggest then why do ‘skeptics’ like to suggest that a few tenths of a Watt reduction in insolation will plunge us into a new mini ice age?
==========================================================================
Are you suggesting no cause and effect between the Maunder Minimum and the LIA? The link had mainstream acceptance 20 years ago, though it is based more on chronological correlation than on any complete understanding of the mechanism. Milankovitch cycles however, overwhelm any contribution from CO2 IR by more than an order of magnitude. The greatly ballyhooed “amplification” of GHG’s in the ice record is accordingly a farce–it hardly comes into play at all–one watt versus 100 TOA. Such is the science your ideology is based on. –AGF
David Spurgeon:
At October 19, 2012 at 12:59 pm you say to me
You did not annoy me so you have nothing to apologise for.
Everybody has “gross ignorance”: the things we don’t know are infinite in number. And that is why we share with each what we each understand and what we think we know.
In this case, I am certain it is important the climate Null Hypothesis is clearly understood by all so the importance of the fact that it has not been falsified is clearly understood by all.
Richard
johanna:
At October 19, 2012 at 3:48 pm you write to me saying
You ask why I needed to be so abusive.
I answer that WUWT is suffering a severe troll infestation that has the clear intent of disrupting threads. Your one-liner is “just a nasty drive-by” typical of troll disruption so I told you to clear-off in as clear a manner as I could.
I don’t doubt you know more about Roman history than me, but even I know your comment is “bollocks”. And if you know more about the subject than me then your post can only have been thew presentation of a falsehood for the purpose of deliberate troll disruption.
If your comment was “semi-frivolous” then you should have indicated that because you presented it as a serious comment. And your post did NOT make a “serious point”: it was plain wrong as tonyb explains at October 19, 2012 at 6:38 am.
The needs for tonyb to provide that explanation (and thus avoid your having misled people) and for me to provide this answer (for the same reason) show the disruptive nature of your posts.
Frankly, I think I may have been too polite to you.
Richard
agfosterjr: What is the maximum globally averaged climate forcing over the course of Milankovitch cycles? How does that compare to, say, the forcing from a change in atmospheric CO2 from 180 to 280ppm?
icarus62:
At October 20, 2012 at 2:51 am you ask
Please explain the reason for your question.
The issue is warmer temperatures in the Holocene and what they indicate – or do not indicate – about likely causes of global temperature rise since the industrial revolution.
Atmospheric CO2 concentration has been increasing from 280 ppmv since the industrial revolution. And the logarithmic relationship of increased radiative effect with increased CO2 concentration indicates that any increase to forcing from CO2 is negligible above 280 ppmv.
Hence, your question seems to be a distraction from the subject of the thread so I would welcome an explanation of its purpose.
Richard
Richard: Refer back to the comment by agfosterjr and all will become clear. I’m trying to establish what his/her claim is based on.
icarus62:
Thankyou for your reply at October 20, 2012 at 4:57 am which answers my question as to the relevance of your questions to agfosterjr which were
Your reply to my question says
As I thought, you have led agfosterjr down a side-track and it is YOUR “claim” which is being addressed. Your questions are an avoidance of his request for YOU to clarify YOUR “claim”. As trolling goes, that is a pathetic diversion of the thread.
I will answer your “claim” to avoid any excuse for the diversion to continue. But first I copy the post to which you referred me so others can clearly see what you are doing.
Firstly, you raised the ‘red herring’ that “a few tenths of a Watt reduction in insolation will plunge us into a new mini ice age”. As agfosterjr says, it is up to you – and nobody else – to justify your assertions.
Secondly, as agfosterjr says the ice core indications are that “The greatly ballyhooed “amplification” of GHG’s in the ice record is accordingly a farce–it hardly comes into play at all–one watt versus 100 TOA”.
Simply, you made a claim and agfosterjr replied saying your claim differs from his understanding and he stated his understanding and why he has that understanding. You have replied by asking him to justify his understanding.
That will not do! You made a claim so you need to justify that claim.
All agfosterjr or anybody else needs to do is to demand the evidence for your claim. He was kind enough to state his understanding which induces him to question your claim, but there is no obligation on him to justify his understanding unless and until you have attempted to justify your claim.
Simply, you must show him yours before he is required to show you his because you started it.
And if you can’t justify your claim then you have lost the argument because you have admitted your claim has no foundation.
Richard
Richard: The WUWT post I referred to above does indeed raise the prospect of a “mini ice age” from just a few tenths of a Watt reduction in insolation. Many similar articles have been written, as I’m sure you’re aware. If the climate is so sensitive to small forcings then agfosterjr’s lack of concern about the climate’s response to the rather larger anthropogenic forcings seems unjustified. Agreed?
Perhaps this will be considered simply another “troll infestation” by RichardsCourtnesy, but I have been waiting to be able to respond to RC concerning the post he placed below. I provide here first his entire post
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richardscourtney says:
October 18, 2012 at 2:31 am
ericgrimsrud:
At October 17, 2012 at 8:03 pm you write to me
So here I have a scientific question for you. As you know, you take exception to my previous statement that the energy balance of the Earth is determined by just three things. They are the intensity of the sun, the Earth’s albedo and the GH Effect. You claim that this is not true and for proof pointed to a scientific reference without explaining what that reference had to say about the point under consideration.
THAT IS A LIE.
In the “claim” at October 17, 2012 at 11:18 am I wrote
There is nothing “honest” about your question because I have already answered it in this thread in a post addressed to you at October 14, 2012 at 9:21 am and in another post addressed to you in another thread.
Perhaps the problem is that the explanation I provided is a quotation – with a link – from Richard Lindzen and his words are beyond your comprehension because he is a scientist.
If you had scrolled up to October 14, 2012 at 9:21 am you could have read
Richard Lindzen states the matter more clearly than I could so I quote his words from
http://www.glebedigital.co.uk/blog/?p=1450
For small changes in climate associated with tenths of a degree, there is no need for any external cause. The earth is never exactly in equilibrium. The motions of the massive oceans where heat is moved between deep layers and the surface provides variability on time scales from years to centuries. Recent work (Tsonis et al, 2007), suggests that this variability is enough to account for all climate change since the 19th Century.
The quotation from Lindzen provides a complete explanation for everybody who knows anything about the thermolhaline circulation and knows radiative flux from a surface is proportional to T^4 so small changes in distribution of the Earth’s surface temperatures have large effect on the average global temperature.
Your knowledge of what is a “scientific question” is as lacking as your ability to understand a scientific answer.
Richard
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RC does not seem to recognize that the three basic forces I referred to concern the most basic of energy transfer mechanisms between Earth and the universe which control the total energy content on the crust of our planet. Of course, there also various flows of that energy WITHIN our planet that cause smalll variations of the measurred average global temperatures at any given point in time. These “natural variations” constitute a different subject, however, that is indeed the one that Lindzen was addressing the reference RC provided. As Lindzen says, however, their affects on T are relatively small, on the order of 0.1 C or so. And these effects will be superimposed on the larger effects that can be expected from changes in the three basic means of energy transfer I described. for energy input and loss from the planet to the universe.
Note that I find no need to unclude personal insults here. Just trying to clarify the science being discussed.
Johanna
I suspect we would have been better able to withsranbd substantial periods of cllimate change in the recent past as we tended to grow a wide variety of crops so if one failed another might work.
My concern is that these days we seem to have a monotone of crops so if one fails all fails. There are huge concerns this autumn with the planting of winter wheat in the Uk. We have a plan A to cope with warming, its high time we had a plan B to cope with cooling
Roman history is fascinating isnt it? I semi frivolously once suggested that WUWT organise a trip in the footsteps of Hanibal over the Alps. He seemed to have a relatively easy time of it compared to today. best regards
tonyb.
eric grimsrud.
Several of us tried to make some helpful suggestions about your short course and the time it took to download. I was also hoping you might put climate into a better historic perspective than you currently do. It has been warming for 350 years as a number of reconstructions show. Dr Mann had his Hockey stick blade upside down so it sloped downwards instead of upwards
tonyb
icarus62 says:
October 20, 2012 at 2:51 am
agfosterjr: What is the maximum globally averaged climate forcing over the course of Milankovitch cycles? How does that compare to, say, the forcing from a change in atmospheric CO2 from 180 to 280ppm?
===========================================================================
Total insolation varies insignificantly, but with hemispherically assymetrical albedo energy to the surface varies enormously. What matters is what the northern hemisphere receives, and as stated, it varies by 100W/m^2 at 65 North, TOA. That’s what it takes to melt the ice. During an ice age the earth reflects much more radiation, and global T falls accordingly. Global T is after all a rough measure of global albedo. M cycles govern the big ice ages and (lack of) sunspots seem to force the little ones. GHG’s are insignificant. –AGF
ericgrimsrud:
Your post at October 20, 2012 at 8:41 am is indeed a ‘troll’ because it refers to a post on another thread than this one and pretends I had not answered your question concerning it. Perhaps you hoped I would not notice your post here?
It seems you are trying to be as egregious as usual. You copied my post to which you refer from the thread at
http://wattsupwiththat.com/2012/10/17/new-paper-confirms-the-climate-was-warmer-1000-years-ago/
In that thread your silly assertion about ‘only three’ climate variables was refuted with explanations by others: e.g.
Lars P. at October 17, 2012 at 11:59 am and further at October 18, 2012 at 11:02 am
phlogiston at October 17, 2012 at 9:06 pm
Indeed, you have NOT been waiting for an explanation from me because two days ago on the first (of three threads) where I refuted your silly assertion i.e.
http://wattsupwiththat.com/2012/10/04/so-much-for-the-theory-that-agw-increases-water-vapor-and-positive-feedback/
I posted the following.
Do not bother me again.
Richard
——————
richardscourtney says:
October 18, 2012 at 2:31 am
ericgrimsrud:
At October 17, 2012 at 8:03 pm you write to me
THAT IS A LIE.
In the “claim” at October 17, 2012 at 11:18 am I wrote
Perhaps the problem is that the explanation I provided is a quotation – with a link – from Richard Lindzen and his words are beyond your comprehension because he is a scientist.
If you had scrolled up to October 14, 2012 at 9:21 am you could have read
The quotation from Lindzen provides a complete explanation for everybody who knows anything about the thermolhaline circulation and knows radiative flux from a surface is proportional to T^4 so small changes in distribution of the Earth’s surface temperatures have large effect on the average global temperature.
Your knowledge of what is a “scientific question” is as lacking as your ability to understand a scientific answer.
Richard
To RichardsCourtney,
I have a couple of reasos for why I could not respond on the other thread. I was not allowed to for 2 days – my several attemts were clearly blocked as you know very well – go back the the Water Vapor threat and see those blocked attempts. I even submitted a personal appeal to Anthony Watts to let my above post through two days ago.
The other reason is that this morning when I tried to post the above statement on that Water Vapor thread, I could not – it appears to me that that threat had been terminated during my 48 hour “time out”.
So why all of your the speculation concerning my “devious motives” for posting on this thread? Only you could come us with them, as you did above. It was the only option I could find – is a far better reason. I certainly did everything I could to continue on the Water Vapor threan – but then this one is fine also – the topic is connected.
I will finsh here with an observation. When our discussions get down to simple basics – as in my comment above – and you find yourself cornered in the scientific topic on the table – you then tend to run away from that table crying foul” and hurling personal insults.
One more thing. I do not appreciate being labelled and dismissed as a “troll”. I have spent my entire life learning science, doing science, and teaching science. Sure I make mistakes sometimes and, when I do, I enjoy learning the new things required to correct those mistakes. I have been intellectually honest at WUWT, Now in my retirement years, I receive no finalcial help and no support of any type, in fact, for my present efferts to “Bridge the Gap of Knowledege and Understanding” that exists between the scientific community and the public. I’ll admit that I have one great fault which is that I tend to respond in kind to the disrespect that the likes of RC spews out routinely. And he tells us that he does this because of his addmitted role at WUWT of casting suspicion on scientiists he considers to be no more than trolls.
icarus62:
At October 20, 2012 at 8:14 am you ask me:
No! Not “agreed”! Flatly rejected!.
The anthropogenic forcings are so trivially small that they can be considered to be zero for all practical purposes. In other words, the man-made global warming from man’s emissions of greenhouse gases (GHG) would be much smaller than natural fluctuations in global temperature so it would be physically impossible to detect the man-made global warming.
Of course, human activities have some effect on global temperature for several reasons. For example, cities are warmer than the land around them, so cities cause some warming. But the temperature rise from cities is too small to be detected when averaged over the entire surface of the planet, although this global warming from cities can be estimated by measuring the warming of all cities and their areas.
Similarly, the global warming from man’s grenhouse gas (GHG) emissions would be too small to be detected. Indeed, because climate sensitivity is less than 1 deg.C for a doubling of CO2 equivalent, it is physically impossible for the man-made global warming to be large enough to be detected. If something exists but is too small to be detected then it only has an abstract existence; it does not have a discernible existence that has effects (observation of the effects would be its detection).
I hold this view because I am an empiricist so I accept whatever is indicated by data obtained from observation of the real world.
Empirical – n.b. not model-derived – determinations indicate climate sensitivity is less than 1.0deg.C for a doubling of atmospheric CO2 equivalent. This is indicated by the studies of Idso from surface measurements
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
and Lindzen & Choi from ERBE satelite data
http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf
and Gregory from balloon radiosonde data
http://www.friendsofscience.org/assets/documents/OLR&NGF_June2011.pdf
Climate sensitivity is less than 1.0 deg.C for a doubling of atmospheric CO2 concentration and, therefore, any effect on global temperature of increase to atmospheric CO2 concentration only has an abstract existence; it does not have a discernible existence that has observable effects.
Richard
agfosterjr: You’re right, total insolation change over Milankovitch cycles is small, amounting to around 0.25W/m². Hence climate feedbacks govern global temperature change in response to these cycles. Of these, the change in albedo that you cited due to ice sheet expansion and contraction (plus vegetation change) is around 3.5W/m², and greenhouse gases contribute around 3W/m² (Climate change and trace gases – Hansen et al 2007). Since global temperature change between glacial maximum and interglacial is around 5°C, that implies a climate sensitivity of around 0.75°C/W/m². Agreed? If not, please cite alternative papers which quantify the forcings and global temperature change over the course of Milankovitch cycles.
Richard: Thanks for the information. If you’re arguing for a very low climate sensitivity then you must disagree with those articles on WUWT and many other blogs about the supposed ‘mini ice age’ which the authors suggest would result from a reduction in solar irradiance of a few tenths of a Watt… is that correct? I don’t want to misunderstand what you’re saying but you didn’t specifically address that point – it would surely only be true if climate sensitivity is very high.
Amazing stuff from all you who have given so much intelligent thought to the topic.
I have some simple (probably simplistic) observations:
We do not have to have a nuclear war to reduce population, we can argue for the major religions to stop encouraging people to have so many children!
Again, simplistically, do we not know that the sun is cooling (as most fires do when they run out of fuel); thus if the sun cools, so will we.
Thirdly, what if any connection is there between volcanic activity, earthquakes and cooling (shrinking) of the earths crust? I’d say cooling is more likely than heating.
icarus62:
Your post addressed to me at October 20, 2012 at 12:12 pm is a complete non sequitur. I quote it all so it cannot be thought I have quoted out of context.
Firstly, as I said in my post at October 20, 2012 at 11:17 am, climate sensitivity is low. It is probably less than 0.5 deg.C for a doubling of atmospheric CO2 and is certainly less than 1.0 deg.C for a doubling of atmospheric CO2.
I am NOT “arguing” for that. In my post at October 20, 2012 at 11:17 am (which you purport to be answering) I have stated it as an empirical fact with references to independent measurements obtained from (a) surface data, (b) satellite data, and (c) balloon data. Reality is what it is and not what you may want to assert.
Secondly, it does NOT follow from the low climate sensitivity that I “must disagree with those articles on WUWT and many other blogs about the supposed ‘mini ice age’ which the authors suggest would result from a reduction in solar irradiance of a few tenths of a Watt”.
There is NOT a direct relationship between radiative forcing and climate. That is your assertion, not mine. If nothing else in the climate system were to change in response to a solar change then that might possibly be true. But everything in the system would change and nobody knows how the system would change. Therefore, nobody knows – and nobody can know – if solar changes were or were not responsible for a ‘mini ice age’. But people post their hypotheses for and against such solar causes on WUWT with a view to having their ideas examined and challenged. That is how science is done (but I know that is incomprehensible to an AGW ‘true believer’ like yourself).
Therefore, you are plain wrong when you assert “it would surely only be true if climate sensitivity is very high”. It may or may not be true and nobody can know if it is true or not.
In conclusion, I suggest you accept the fact that the AGW-hypothesis is a ‘busted flush’. It ended in Copenhagen in 2009. Promotion of the AGW-hypothesis for political reasons has inhibited the advance of climate science for two decades, and it is a matter of rejoicing that it is – at last – being rejected now the politicians’ promotion of it has ended.
Richard
Icarus62 says:
October 20, 2012 at 12:00 pm
====================================================
Hansen’s paper is an ideological joke. Really. Have you ever seen a graph comparting Milankovitch cycles with T/GHG’s? They tally very nicely, albeit with a lag of about 5ky. There simply is no sound disputing of the correlation between M cycles and T/CO2. Now do you understand what a problem this presents for Hansen’s old claim that CO2 is doing the forcing? We have clear correlation between M cycles and T.
So I ask you, is CO2 governing the earth’s orbit? That’s what Hansen would have us think, and I have a hard time believing he is that stupid. Rather he is that dishonest. We can’t have both M cycles and GHG’s driving T unless GHG’s drive M cycles. What counts is what melts the ice, and it is clear that the 100W/m in the mid northern latitudes is what’s doing it. Once the ice melts the reduced albedo makes for another 300W/m–double that after a forest grows. If only 1% of the earth were covered by variable ice caps then Hansen’s figure of 3W (globally?) would mean something, but he seems to be comparing global average albedo forcing to locally calculated GHG IR. Otherwise we should have an easily measured radiation increase, and we haven’t measured anything yet, especially on the order of 100W by which we know M cycles vary at TOA.
That fool Hansen claims T tracks CO2 and he ignores M cycles. How could he get any dumber? What does he think drives CO2 and why? Albedo drives CO2 and T in tandem, though CO2 lags T by half a millenium. So here’s how it is: insolation melts ice and lowers albedo, raising T and CO2. CO2 doesn’t force anything.
–AGF
Richard: A fast feedback climate sensitivity as low as you suggest is ruled out by palaeoclimate and 20th/21st Century temperature observations – there is little realistic chance of it being lower than 0.5°C/W/m², with 0.75°C/W/m² being the best estimate from the data. The Earth System Sensitivity between Holocene and warmer climate states is less certain but could well be double that or more (i.e. >6°C for a doubling of atmospheric CO₂ from 280 to 560ppm). We’re fortunate that the lag in the climate system gives us a chance to avert the worst of the warming, but we do have to actually act on the best information, not ignore it and be complacent.
Icarus62 says:
October 20, 2012 at 3:59 pm
“…but could well be double that or more (i.e. >6°C for a doubling of atmospheric CO₂ from 280 to 560ppm).”
=========================================================
Well then, it should have gone up 3 degrees for a half log doubling, 280 > 390ppm. Do you think it has? Does anyone? –AGF
agfosterjr: I suggest you read the paper I cited, and others by Hansen, as you seem to have the wrong end of the stick entirely. Hansen points out that the change in atmospheric CO₂ (and other greenhouse gases) over the course of Milankovitch cycles is a feedback – perhaps you could explain how you came by this odd idea that CO₂ is the forcing? Anyway, if you’re disputing the values given by Hansen’s research then by all means cite the ones you think are more realistic. What is the total forcing from all climate feedbacks over the course of Milankovitch cycles, and what is the global temperature change? If you have those figures then we can work out what you think climate sensitivity is for that scenario.
Icarus62:
At October 20, 2012 at 3:59 pm you lie
Absolutely false!
I did NOT “suggest” anything. I cited the direct observations in my post at October 20, 2012 at 11:17 am where I wrote
Either cite a reference which supports a higher measurement of climate sensitivity than the results I have cited or apologise for your deliberate falsehood.
I shall only reply to further posts from you by repeating this demand until you provide the needed reference or apology because discussion based on lies is pointless.
Richard
agfosterjr: So far the observed warming is only consistent with a climate sensitivity of 0.75°C/W/m² (3°C for a doubling of atmospheric CO₂ from 280 to 560ppm), but isn’t that what we’d expect at this early stage? The longer term climate feedbacks haven’t had much time to kick in yet (fortunately for us). I agree that the evidence isn’t as good for a high ESS but do you have any good reason to rule it out? Wouldn’t it be prudent to do our best not to find out how high it really is?
As I was “trolling” through this thread, I found a classic, but stupid comment often parroted by the” pseudo experts” of AGW. Guess who deliivered it – none other than my friend, Richardscourthey. At about 3:15 am on Oct 22 he said:
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“Atmospheric CO2 concentration has been increasing from 280 ppmv since the industrial revolution. And the logarithmic relationship of increased radiative effect with increased CO2 concentration indicates that any increase to forcing from CO2 is negligible above 280 ppmv.”
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His statement is abolutely sophomoric in that such a “logarithmic” relationship would indeed be expected if the GHG’s only absorbed IR radiation. That is not the case, of course, they also emit IR radiation as well and for such systens the radiative effect is well known to continue well behond the point of absorption saturation. Thus, nearly the same T increase is expected for every doublling of the GHG concentration. Thius our persent increase from 280 to 394 ppm is VERY significant.
I would welcome the opportunity to argue this criitically important point out with RC if he wishes. The new and even old literature makes this point clear. I suspect, however, that he has learned not to talk on folks at WUWT who actually know of some of the very basic aspects of cimate change. Too bad – this is a very important and oftern misunderstood point.
ericgrimsrud says:
“…nearly the same T increase is expected for every doublling of the GHG concentration. Thius our persent increase from 280 to 394 ppm is VERY significant.”
Not really. As we see, the planet itself is falsifying grimsrud’s alarmist nonsense.
icarus62 says:
October 20, 2012 at 4:36 pm
agfosterjr: I suggest you read the paper I cited, and others by Hansen, as you seem to have the wrong end of the stick entirely. Hansen points out that the change in atmospheric CO₂ (and other greenhouse gases) over the course of Milankovitch cycles is a feedback – perhaps you could explain how you came by this odd idea that CO₂ is the forcing? Anyway, if you’re disputing the values given by Hansen’s research then by all means cite the ones you think are more realistic. What is the total forcing from all climate feedbacks over the course of Milankovitch cycles, and what is the global temperature change? If you have those figures then we can work out what you think climate sensitivity is for that scenario.
=====================================================================
“…perhaps you could explain how you came by this odd idea that CO₂ is the forcing? ”
–Meaning of course my reading of Hansen. But did you not look at his first chart? Captioned thus:
“Figure 1. (a) Greenhouse gas forcing and Vostok temperature: Antarctic temperature (left scale)
from Vostok ice core…”
And where does he get the precision for his albedo graph? Can he figure ice sheet are from ice volume alone? He invents an albedo/T lag to suit his dogma.
Hansen: “Our emphasis is on planet Earth as a whole.”
Thus he quantitatively ignores the mechanism: what melts the ice? Global T does not. Northern insolation does–100W/m^2 amplified by regional albedo feedback of up to 5x. Global T is an effect–an irrelevant averaging–not the cause. Insolation is the cause; albedo/T/CO2/CH4 follows about 5ky later as the ice slowly melts–or freezes. (The sensitivity applies to cooling too, you know.)
Hansen: “If our interpretation of near synchroneity of forcing and ice sheet
response is correct, implications for humanity are profound.”
Hansen proposes that the ice melts quickly due to instant insolation rather than gradually over milllenia–therefore we should be very worried. How likely is such top down melting? We’re talking about ice nearly two miles high, just like Antarctica, where summer insolation is the highest in the world: 540W 24 hour average. Elevation matters more than latitude. Ice is seen to melt at the perimeter and low elevations–not top down. That’s why the long lag is the rule.
More importantly you have ignored the main problem: it takes 100 extra watts to melt the ice. CO2 IR provides about a watt of “amplification.” Do you deny this? How do you get around the absurdity of GHG feedback when we’re talking about a 1 or 2 percent addition where the ice is melting? –AGF
Richardscourtney said:
The needs for tonyb to provide that explanation (and thus avoid your having misled people) and for me to provide this answer (for the same reason) show the disruptive nature of your posts.
Frankly, I think I may have been too polite to you.
Richard
————————————————
He also accused me (by association) of being a troll.
Richard, I have been posting here for some years, as I do on Bishop Hill, Steve McIntyre’s, Judith Curry’s and others, all under the same name. I am not remotely a ‘troll’, as you will find if you can be bothered checking.
You attribute a significance to a brief passing comment that it does not hold.
Why are you being so aggressive and unpleasant?
To D Boehm,
Yes, Really, The sensiitivity to CO2 with the fast feedback is thought to be about 3C. We have not yet doubled CO2, but have increased it by 40% . The particulate pollution of mankind has masked about 1/2 of the GHG warming. Also, the thrermal inertial of the Earth delays the warming. And the Earht has warmed by about 0.8 C since the pre ind era. So, Yes Really !
ericgrimsrud,
Not really. There is no measurable AGW. For that matter, there is no warming. Wake up to reality.
tonyb:
While it is true that there was a lot more diversity in the plants and animals that people raised for food in the ancient (and early modern) world, the yields were so low, especially for grain crops, that a bad season was truly devastating. The animals were smaller and had less meat, so if a lot of them died of cold or starved, the losses could easily lead to human starvation.
One of the great benefits of living in this era is that a crop failure or animal deaths do not mean starvation for the local populace – thanks to fossil fuelled transport and refrigeration. I think that we are so inured to this problem that we underestimate how significant it was in the past. Even 2 or 3 hundred years ago in England, rural peasants (and especially their children) routinely died of malnutrition in bad seasons.
As for recreating Hannibal’s trip – great idea, but I want a heated howdah!
ericgrimsrud:
At October 20, 2012 at 6:20 pm you quote my having said the correct and accurate statement
You then spout some ignorant twaddle before saying
I welcome and enjoy discussing things on WUWT with every person who knows at least the basics of climate. And I enjoy a rational argument with anybody. For both reasons, I don’t enjoy any interaction with you.
In this case, I am fortunate in not needing to discuss the matter with you because in this thread I have twice explained and fully justified my correct statement with references and links. You are plain wrong (as usual). See my posts at October 20, 2012 at 11:17 am and October 20, 2012 at 4:49 pm.
Richard
ericgrimsrud: Exactly right. A low climate sensitivity is ruled out by the data. That, combined with the fact that the anthropogenic greenhouse gas emissions causing the warming are rising faster than ever, is why it’s now becoming widely accepted that we won’t avoid 2C of global warming above mid-20th Century global temperature – unless someone comes up with some effective geo-engineering solutions.
johanna
What you say is undoubtedly true but what is different now are surely the sheer numbers of people living on a ‘just in time’ manner dicated by supermarkets and where there are limited surpluses of food . In the past a catastrophe was likely to be limited in extent (Irish famine accepted) but now it could be a worldwide event. Plan B is needed.
Can’t manage the heated howdah as hadn’t anticipated actually taking Elephants. Its an intriguing idea though and would get lots of publicity.You can be in charge of them
By the way I did not remotely accuse you of being a troll by association. I recognise your name hence the friendly nature of my response.(although I am even quite nice to eric grimsrud!)
I take it you are British? I am from the Exeter area.
Tonyb
Icarus62:
At October 21, 2012 at 12:22 am you assert
NO! That is a falsehood. There is no empirical data which agrees with your assertion and that is why you have not provided and/or referenced any.
“The data” has been repeatedly referenced and linked to sources by me in this thread. The measurements ALL show climate sensitivity is less than 1.0 deg.C per doubling of atmosopheric CO2 concentration and it is probably less than 0.5 deg.C per doubling of atmosopheric CO2 concentration.
That is what the data independently derived from surface measurements, from ERBE satellite measurements, and from balloon radisonde measurements each shows.
Your superstitious don’t change that.
Richard
Friends:
At October 21, 2012 at 12:22 am Icarus62 says
In reality global temperature will rise by nearly double that in the 6 months from next June.
Each year the global temperature rises by 3.8 deg.C between June and January then falls by 3.8 deg.C from January to June. And nobody notices.
Richard
johanna says:
October 20, 2012 at 7:30 pm
Even 2 or 3 hundred years ago in England, rural peasants (and especially their children) routinely died of malnutrition in bad seasons.
======================================================================
Child mortality (5 and under) among the Aymara of southern Peru was estimated at 38% in 1988–but mostly perinatal, with some infanticide suspected.
http://www.ncbi.nlm.nih.gov/pubmed/3258073
And you surely know what rising grain prices due to methanol diversion have have done to 3rd World countires. –AGF
Icarus62 says:
October 21, 2012 at 12:22 am
ericgrimsrud: Exactly right. A low climate sensitivity is ruled out by the data. That, combined with the fact that the anthropogenic greenhouse gas emissions causing the warming are rising faster than ever, is why it’s now becoming widely accepted that we won’t avoid 2C of global warming above mid-20th Century global temperature – unless someone comes up with some effective geo-engineering solutions.
============================================================================
What gibberish! In the first place warmer is good. Learn that. In the second place your global figures are meaningless–how many times do I have to repeat it? You continue to ignore the mechanism, following Hansen’s intentional misleading. You suffer from invincible ignorance. Respond to this if you can: Albedo is controled by ice sheet extension. Ice sheets are melted by extra June insolation of about 100W TOA. Not 3W; not 1W; 100W TOA, which transmits to about 70W at the surface, which through the process of disappearing ice (at the edge–not CO2) is amplified by the local albedo decrease (not global–that’s the effect, not the cause). Ice albedo is between .5 and 1. Forest albedo is near zero. Multiply 500W by 10% of the earth’s surface covered by ice, and you don’t get a global albedo change of 3W–more like 50 –can’t you do the math? Hansen sure can’t. CO2 has nothing to do with it. Please address this or shut up. You simply reveal your Hansenian ignorance by spouting of this irrational alarm–it has no science behind it–only incompetence and stupidity. –AGF
agfosterjr:
At October 21, 2012 at 6:03 am you say
And you surely know what rising grain prices due to methanol diversion have have done to 3rd World countires (sic)
Yes. I think you may want to read my paper at
http://scienceandpublicpolicy.org/originals/biofuel_issues.html
Richard
Note RichardsCourtney’s “explanation “ of a CO2 sensitivity below 1.0 C below:
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In this case, I am fortunate in not needing to discuss the matter with you because in this thread I have twice explained and fully justified my correct statement with references and links. You are plain wrong (as usual). See my posts at October 20, 2012 at 11:17 am and October 20, 2012 at 4:49 pm.
Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Upon looking up those previous posts all one finds is repetitions of the claim that sensitivity is less than 1.0C and references to a few articles that he claims proves the point. Upon looking up those references, however, no such proof is found. Most importantly, RichardsCourtney cannot tell you what exactly it was in those papers that proved his claim.
Thus, he avoids scientific discussion in this manner. In his case, this is a good strategy because he has repeatedly shown that he cannot carry a scientific argument by himself. Statements of so called “fact” with references he cannot explain are all you will get.
His repeated claim to be supported by “observations” is also bogus and I am sure he would not want to explain all of that either. For example and just for starters, why was the Earth so warm about 50 mYrs ago when the Earth was a “waterworld” and alligators lived in Alaska? The only three possible explanations for such a huge difference from today would be a hotter Sun, a much lower albdedo, or a much stronger GH effect. Does he suppose that those differences are also due to “natural variations” ?
While it would be interesting to hear what RC thinks about that very simple and readily understood question, you can be sure he will ignore it. It is in discussions of the simple and obvious questions that the pseudo scientists get exposed. Just watch. If we get any response to this simple question, it will be goppelygook broken only with personal attack and insults.
To Agfostorjr,
You really seem to have things figured out. Perhaps you could even explain the PETM for us. Those of us with less imagination have the notion that 56 mYs ago a huge carbon burst (CO2 and / or CH4) occurred throughout the globe and this caused T to rise very signiicantly, lasing about 150,000 years.. Perhpas you could help us overcome our incompetance and stupidity on that one. I mean, after all how coulda burst of CO2 possibly cause an incrrease in global temperature. It must have been due to some other “natural variation”, right, that just happened to coincide with that carbon explosion.. Or maybesome ice just happened to dissappearr …….ops, there was no ice anywhere on the planet back .then. Or maybe …….. nope. You can see we need your help on that bit of relatively recent (geologically speaking ) history.
agfoster jr says to grimsrud:
“You suffer from invincible ignorance.”
LOL! A perfect grimsrud description. Could not be more accurate.
Now grimsrud has to go all the way back to the PETM [or “PEMT”, as he kept calling it before I corrected hiim] in order to cherry-pick what he believes explains everything. But in fact, the rise in CO2 followed the PETM as usual. Just like today.
Grimsrud cannot produce a chart showing that rises in CO2 are followed by rises in global temperature. Therefore, all he is engaging in is baseless speculation. As usual.
[snip . . you would need to provide some proof of these assertions rather than just stating them otherwise it is just trolling . . mod]
agfosterjr: The 3.5W/m² of albedo forcing from ice sheet and vegetation changes comes from the findings of Hewitt and Mitchell 1997. If you can cite a paper which gives a much larger figure (and hence a lower climate sensitivity than 0.75°C/W/m² (3°C for a doubling of atmospheric CO₂ from 280 to 560ppm), then by all means do so.
Friends:
ericgrimsrud says in his post at October 21, 2012 at 9:50 am
Firstly, it is a fact and NOT merely a “claim” that – as I said – empirical (n.b. not model-derived) determinations indicate climate sensitivity is less than 1.0deg.C for a doubling of atmospheric CO2 equivalent. This is indicated by the studies of Idso from surface measurements
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
and Lindzen & Choi from ERBE satelite data
http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf
and Gregory from balloon radiosonde data
http://www.friendsofscience.org/assets/documents/OLR&NGF_June2011.pdf
Anybody can click a mouse to check the fact for themselves. Grimsrud’s post merely – again – demonstrates his inability to read or – alternatively – that he is a liar.
Richard
DBoeihm is now rewriting the evidence concerning the PETM – when he says
“But in fact, the rise in CO2 followed the PETM as usual. Just like today”.
I would love to see the charts or graphs he is reading. Since they don’t exist, I’m sure we will not see any such evidence. I suspect that he might need some help reading his charts again, just are he did before – maybe Kadaka could help again..
And concerning his “just like today” comment. Could it possibly be that DBoehm thinks the 40% increase in CO2 we has seen over the last 150 years is due to a the small T increase we have also seen over this period. Kadaka, where are you? Help?
Friends:
Further to my earlier post, I add these extracts. From each of the links.
Idso SB, Climate Research (1998)
(Determinations from surface data)
And in view of the relative weakness of the CO2 greenhouse effect at current atmospheric CO2 partial pressures, as revealed by the natural experiments I have described herein—a likely warming of only 0.4°C for a 300 to 600 ppm doubling of the air’s CO2 content—these CO2-induced cooling forces could potentially negate a large portion (or even all) of the primary warming effect of a rise in atmospheric CO2, leading to little net change in mean global air temperature.
[i.e. a climate sensitivity of ~0.4°C for a doubling of the air’s CO2 content : RSC]
Lindzen RS & Choi L-S , Geophysical Research Letters (2009)
(Determinations from ERBE satellite data)
For sensitivities less than 2°C, the data readily distinguish different sensitivities, and ERBE data appear to demonstrate a climate sensitivity of about 0.5°C which is easily distinguished from sensitivities given by models.
And
Finally, it should be noted that our analysis has only considered the tropics. Following Lindzen et al. [2001], allowing for sharing this tropical feedback with neutral higher latitudes could reduce the negative feedback factor by about a factor of two. This would lead to an equilibrium sensitivity that is 2/3 rather than 1/2 of the non-feedback value. This, of course, is still a small sensitivity.
[i.e. a climate sensitivity of ~0.4°C for a doubling of the air’s CO2 content : RSC]
Gregory K, Friends Of Science (2011)
(Determinations from radiosonde ballloon data)
This analysis shows that there has been no significant increase in the greenhouse effect since 1960. The greenhouse effect as characterized by the normalized greenhouse factor has increased by only 0.19% from 1960 to 2008. The temperature change from 1960 attributable to AGW is less than 0.1 °C. The extrapolated temperature change attributable to AGW at doubled CO2 concentration is 0.26 °C. Delaying the start date of the analysis year by year to 1970 gives calculated climate sensitivities that vary about the 0.4 Celsius value.
[i.e. a climate sensitivity of ~0.4°C for a doubling of the air’s CO2 content : RSC]
n.b. The three studies each determine a climate sensitivity of ~0.4°C for a doubling of the air’s CO2 content.
I remind that I conservatively said these papers report a a climate sensitivity of less than 1.0°C for a doubling of the air’s CO2 content.
But the egregious Eric Grimsrud asserted
The quotations I have here provided demonstrate that both of his assertions are falsehoods.
Richard
ericgrimsrud says:
“I would love to see the charts or graphs he is reading. Since they don’t exist, I’m sure we will not see any such evidence.”
Pure projection. Grimsrud cannot produce the chart I keep asking him for. That is because there is no such chart. ∆CO2 does not cause any measurable ∆T.
Prove me wrong, if you can. Post your non-existent chart.
ericgrimsrud says:
October 21, 2012 at 2:28 pm
“Could it possibly be that DBoehm thinks the 40% increase in CO2 we has seen over the last 150 years is due to a the small T increase we have also seen over this period?”
Eric are you admitting that we have seen only a small T increase over the past 150 years? Careful when you are looking down on your superiors that you don’t make such Freudian slips.
When Richardscourtney uses the word “proof”, to him it means that some scientist somewhere has offered an explanation for their observations that RC likes. His repeated misuse if that word shows that RC is no scientist.
In addition, if he had followed the literature in recent years, he would know that the paper he cites by Lindzen and Chio has been ripped to sheds both because of flawed measurements and the mis interpretation of their data- ever since it’s publication in ’09..
A little lesson here for RC: complex relationships are never “proven” beyond all doubt. Papers appear and they sometimes make claims and deductions. Those experiments and claims are then tested by others. A point is seldom proven but is frequently suppoered in follow up studies. The L and C paper did not even make the latter grade. Yet, because the L and C paper offered the explanation RC wanted, he now thinks he is providing “proof” for something just by pointing to some carefully selected references that have already failed to pass the test of time. .
Gary, So far we have seen about 0.8 C increase in T. Do you also think that caused the 40% increase we have seen in atmosphereic CO2.? You might what to check with your supervisors before agreeing with DBoehm on that one.
ericgrimsrud says:
“When Richardscourtney uses the word ‘proof’, to him it means that some scientist somewhere has offered an explanation for their observations that RC likes. His repeated misuse if that word shows that RC is no scientist.”
Richard Courtney is a published, peer reviewed scientist. And he is someone you have previously been forced to apologize to for your baseless attacks. Obviously, your apology was insincere, since you continue to make the same ad hominem attacks — which reflect badly on your own lack of character.
Since DBoehm thinks that
∆CO2 does not cause any measurable ∆T.”
I wonder why he thinks the world was about 12 C warmer some 50 mYrs ago. . Was the Sun hotter? Was the albedo that much lower even though most of the total albedo is caused be cloulds? Gosh, what else might it have been given “DBoehm’s Law” shown above. It must have been “natural variation” right? Or , maybe the Laws of Nature have changed since then – that was a long time ago,right?
Kadada, maybe you could help DBoeihm with this one also. Its really a tough one to deal with given “DBoehm Law”.
ericgrimsrud:
re your post at October 21, 2012 at 3:29 pm.
YOU LIED.
I showed you lied (yet again). And instead of apologising you provide weasel words and say I used the word “proof”. That is another lie. I only use the word “proof” with regard to mathematics.
“Proof” is a word used by pseudoscientists; e.g. you. It is not used by scientists; e.g. me.
The three papers each analyse different data and they each obtain the same result for climate sensitivity. RC and SkS have attacked one of the papers but have failed to publish a significant flaw in it.
All the evidence for the magnitude of climate sensitivity is – as I said – that climate sensitivity is less than 1.0°C for a doubling of the air’s CO2 content. Your superstitious beliefs do not and cannot change that fact.
APOLOGISE FOR YOUR LIES then crawl back under your bridge.
Richard
ericgrimsrud,
You have provided zero scientific evidence showing that the rise in CO2 has caused any global warming. You base your belief on a short term, coincidental correlation that began breaking down over a decade and a half ago.
But if you have any empirical evidence that the rise in CO2 is the cause of global warming — or even part of the cause — then by all means, post it here and now. Be sure to abide by the scientific method, and remember that models are not evidence. Be prepared to show explicit and verifiable cause-and-effect, or you will be laughed at once again for your invincible ignorance.
One more time: ∆CO2 does not cause any measurable ∆T. Your comments amount to mere hand-waving, because you have produced no scientific evidence to refute natural variability. If it were not for your hand-waving, and cherry-picking of outlandish examples from millions of years in the past, you would not have anything to say. As it is, your baseless comments are pseudo-scientific nonsense, and thus very easy to debunk.
BTW — where is that chart showing that ∆CO2 causes ∆T? Still looking for it? Here’s a hint: it doesn’t exist. You have cause and effect reversed, that’s all.
icarus62 says:
October 21, 2012 at 1:42 pm
agfosterjr: The 3.5W/m² of albedo forcing from ice sheet and vegetation changes comes from the findings of Hewitt and Mitchell 1997. If you can cite a paper which gives a much larger figure (and hence a lower climate sensitivity than 0.75°C/W/m² (3°C for a doubling of atmospheric CO₂ from 280 to 560ppm), then by all means do so.
=============================================================================
In fact the paper you cite gives a figure of 5W due to “Topography and surface albedo” (Table 5) and 50W local forcing (p.827a, top), both averaged out over the year and the 5W averaged out over the globe. To better make my point, assume a planet like ours but latitudinally symetrical. Would it be safe to deduce alternating ice ages in both hemsipheres? Global T and surface albedo would be the same whether you happened to be in or out of an ice age–an ice core would tell us little about climate. Now according to Hansen such a scenario would not work since the symmetry would not allow for GHG asymmetry. That is, our hemispherical asymmetry allows for GHG’s to accumulate very roughly out of phase with receding ice caps, which could not happen if the opposite hemisphere were going into an ice age at the same time.
So if you understand the argument and agree with its presentation you have to ask yourself, which world is realistic: would there be ice ages in a world just like ours except with symmetrically configured continents? Hansen says no. What do you say?
And getting back to the albedo, if we were to assume your paper’s 5W global average, and ignore southern ice formation, that “un-averages” to 10W in the north, and 40W in the northern summer quarter. Your paper’s 50W local average would “un-average” to 200W summer quarter if there were no insolation asymmetry, and of course it is that asymmetry which starts the melting in the first place–and extra 100W/m TOA in June.
Hansen is like a fire chief who disables the alarm system in favor of a thermometer stuck on a station window. –AGF
Ericgrimsrud: not even your people blame the 95% of earth’s warm climate history on CO2. Plate tectonics are usually invoked, altering wind and ocean currents. –AGF
Kadaka, Please explain to DBoehm how silly his comment is:
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
“BTW — where is that chart showing that ∆CO2 causes ∆T? Still looking for it? Here’s a hint: it doesn’t exist. You have cause and effect reversed, that’s all.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
He apparently does not know that plots do not necessarily show cause. They might show correlation – if there is cause – but they do not prove cause. Similarly why would DBoehm suggest that that same plot proves cause in the reverse direction?. The notion of a cause is provided only by a theory..
I hope you don’t mind that I have asked you for your help in communicating with DB. You two seem to be on a similar wavelength so I just thought your chances of getting through might be better.
And if you understand why he is asking me for a chart all the time, please let me know.. If it Is just so that he can then tell me that correlation does not prove causes, please help him understand that we all already know that.
Grimsrud,
Begging for someone else to support your nonsense beliefs is über lame.
Post a chart showing that a change in CO2 causes a change in temperature, or you lose the argument. Simple as that.
[snip – reword this, not your blog to make demands on – Anthony]
Anthony:
re your snip of my post at October 21, 2012 at 11:23 pm.
Yes,
it is your blog and you can allow or forbid any post you choose to be posted on it,
I write to make a request.
Following other lies about me on other threads, Grimsrud made a series of lies about me on this thread. Here he made repeated claims that
*a) I asserted a series of papers said other than they do
and
(b) they do not contain specific information that I said they did.
Those assertions were more of his personal attacks and I showed that they were lies. They were posted on this blog in this thread.
I demanded that Geimsrud apologise. He did not but made excuses and I complained.
He still did not apologise and I repeated my demand in strong – but not profane – terms,
You have snipped that saying
“[snip – reword this, not your blog to make demands on – Anthony]”
OK. Then please snip any further lies about me from Grimsrud. There have been too many on too many WUWT threads.
Richard
To RichardsCourtney
Have you seen
“Trenberth et al
Relationships between tropical sea surface temperature and top-of-atmosphere radiation. Geophys. Res. Lett., 2011.
In it, Lindzen and Choi 2009 is shown to be wrong on several fronts. If you don’t actually read papers and cannot figure out where the problems with L and C are, I would be pleased to summarize them for you on a following post.
Hope you are feelling better.
Eric
ericgrimsrud says:
October 21, 2012 at 9:05 pm
=========================
Centuries of data correlating the cock’s crow and sunrise show strong agreement, albeit with a lag of less than an hour. We may safely conclude that one event causes the other, or that a third event causes both. This chart (http://en.wikipedia.org/wiki/File:Vostok_420ky_4curves_insolation.jpg)
compares insolation governed by orbital forcng (Milankovitch Cycles) with T and CO2, and again shows good agreement, especially between T and CO2. Again we can assume either T or CO2 drives the other or that a third function governs both. But we have a third function, insolation, governed by the earth’s orbit, which correlates with the other two, generally leading it by c.5ky. So now we have to ask, is T or CO2 driving insolation, or is insolation running the show? Does the rooster make the sun come up? And the claim that CO2 forces T is every bit as absurd. Insolation causes ice sheet growth or melting, which governs T and CO2. And as I’ve been arguing all along, CO2’s contribution to warming is of 2 orders of magnitude less than insolation and albedo feedback combined. That means insignificant. This year the high southern latitudes will get 30 more watts of January insolation than the opposite northern latitudes will in June:
http://aom.giss.nasa.gov/cgi-bin/srmonlat.cgi
–AGF
ericgrimsrud:
re your post tp me at October 22, 2012 at 7:50 am
I will not lower myself to discuss anything with you unless and until you provide a complete, abject and unequivocal apology for your lies.
Anyway, as this thread demonstrates, it is a laughable idea that you are capable of understanding the paper which you cite.
Richard
To RC, Have a good laugh:
The huge problem with the Lindzen and Choi 2009 paper is that they examine only select tropical data. In their chosen data set, they find that during periods of higher surface temperatures, the IR radiation emitted and solar radiation reflected back into space by the earth goes up as well, thereby cooling the Earth. To show this, they select specific intervals of monthly averaged values and compare fluxes at their endpoints. They don’t even provide a criterion for selecting these endpoints, they simply pick some for analysis.
The result one then obtains in depends entirely on the endpoints chosen. The article by Ttrenberth et al shows that the perceived feedback can be whatever one wishes it to be by choosing different intervals and that the result that obtained by Lindzen and Choi is actually very unlikely.
In sort, much more robust sampling is required.
ANd there is much more — later.
Eric Grimsrud:
I await your apology.
I have no interest in your misunderstandings of a paper which you lack the competence to understand. And I doubt that anybody else is interested, either.
I await your apology.
Richard
RC,
You will have a long wait. I am not inclined to apologize to bullies who hand it out in spades and then turn into crybabies when treated in kind.
I will, however, continue explaining the fatal flaws of the Lindzen and Choi paper in a future post or two.
And why would you claim to know what everyone else is interested ? Do you think you run the place?. You have hung your entire case for low sensitivity above on the Lindzen and Choi paper, even though you can’t explain its contents. .Therefore, I suspect that many others might like to know more about its contents – something you have been unable to provide – other than countless repetitions of its erroneous conclusions.
I understand that you are trying the “head off” this pending discussion of science. Again that is when we generally see only your backside along with a few personal insults. But should you regain your interest in the actual science on which you pontificate, please feel free to point out any errors I might make it representling the scientific content of the two papers in question.
Eric
ericgrimsrud :
re your post at October 23, 2012 at 12:43 pm.
I still await your apology for your lies. A man would have provided it by now.
It is not bullying to object to blatant personal lies from a troll.
I don’t run away from you. Why would I? You have the intellect – but not the work rate – of a fly and you are easier to swat. And, as you have so often demonstrated, you lack competence to discuss science.
Copy as many misleading statements from SkS as you want. It will have no effect. Lindzen&Choi are right and their work is confirmed by the other completely independent studies.
Incidentally, I point out that I have a surprisingly high respect for you in that in terms of respect I rank you only two places below a slime mold.
I await your apology. If it is sufficiently grovelling then it may improve my respect for you.
Richard
To RichardsCourtney and any other parties who are interested in the scientiifc content of Lindzen and Choi 2009 and not simply their conclusions.
Another exceedingly important deficiency in L&C, 09 appears to occur in their calculations of CO2’s Sensitivity. They did not include the effects of black body radiation in their feedback parameter. This omission resulted in a net feedback that was negative thus leading to their prediction of low Sensitivity. Inclusion of the radiation effect leads to a positive feedback parameter and a much greater estimate of Sensitivity.
This deficiency of L&C 2009 and others, such as the other one I described in another recent post above, are described extensively in Trenberth et al 2010.
My main point here is not to be overly critical of the paper by L&C. That paper made suggestions that were novel and perhaps worthy of consideration, but were also contrary to more generally accepted thought. It is not surprising therefore that there will be counter arguments and corrections to their paper. That’s how science works.
But my main point here is: for Richardscourtney or anyone else to embrace the conclusions of L&C before that paper has withstood the test of time is most unwise. It already appears that the conclusions of L&C are very probably not valid after a very short test of time.