This is part 8, essentially a wrapup see all other parts 1-7 here: http://kenskingdom.wordpress.com/
Guest post by Ken Stewart, July 2010
“…getting seriously fed up with the state of the Australian data.”
(Harry the mystery programmer, in the HARRY_READ_ME file released with the Climategate files.)
He’s not the only one. In a commendable effort to improve the state of the data, the Australian Bureau of Meteorology (BOM) has created the Australian High-Quality Climate Site Network. However, the effect of doing so has been to introduce into the temperature record a warming bias of 41.67 %. And their climate analyses on which this is based appear to increase this even further to around 66.67%.
This post is the summation of what I believe is the first ever independent check on the official climate record of Australia. It is also the first ever independent check on the official record of an entire continent.
I will try to keep it simple.
Here is the official version of “the climate trends and variations in the Australian instrumental record” published for the Australian public, the government, and all the world at http://www.bom.gov.au/climate/change/aus_cvac.shtml
Trend Map, 1910-2009:
Time Series Graph using their handy trend tool:
0.1 degree C per decade, or 1 degree per100 years.
In the BOM website appears this explanation:
The temperature timeseries are calculated from homogeneous or “high-quality” temperature datasets developed for monitoring long-term temperature trends and variability …….. Where possible, each station record in these datasets has been corrected for data “jumps” or artificial discontinuities caused by changes in observation site location, exposure, instrumentation or observation procedure. This involves identifying and correcting data problems using statistical techniques, visual checks and station history information or “metadata”.
and
“High-quality” Australian climate datasets have been developed in which homogeneity problems have been reduced or even eliminated.
I have given a very brief summary of this process in http://kenskingdom.wordpress.com/2010/05/12/the-australian-temperature-record-part-1-queensland/
(I should point out that this method was changed somewhat by Della-Marta et al (2004) who also used a distance weighting method as well and included some urban stations and stations with much shorter records.)
Torok and Nicholls (1996), authors of the first (published) homogenization, rightly state that
“ A high-quality, long-term surface air temperature dataset is essential for the reliable investigation of climate change and variability.”
Here is the map showing the 100 currently used High Quality stations that supposedly meet this requirement:
Before my first post, I asked BOM to explain some of the odd things I had noticed in the Queensland data. Amongst others, this statement by Dr David Jones, Head of Climate Monitoring and Prediction, National Climate Centre, Bureau of Meteorology, in an email dated 25 April 2010, caught my eye:
“On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).”
This statement has been the yardstick for this study.
Not having access to the list of stations, the metadata, the software used, or the expertise of BOM, the average citizen would normally accept the published results as they stand. However I wanted to have a closer look. Surely the results of any adjustments should be easy to compare with the previous record.
I downloaded annual mean maxima and minima for each of the sites from BOM Climate Data Online, calculated annual means and plotted these. Frequently, two or three stations (some closed) were needed for the entire record from 1910-2009, and even then there sometimes were gaps in the record- e.g. from 1957 to 1964 many stations’ data has not been digitised. (But 8 years of missing data is nothing- many stations have many years of estimated data “filled in” to create the High Quality series). I also downloaded the annual means from the High Quality page, and plotted them. I then added a linear trend for each.
I have exhaustively rechecked data and calculations in all 100 sites before compiling this summation. I have decided to amend only one, Bowen, by creating a splice by reducing early data and omitting some data, so that the trend matches that of HQ. This is on the basis of no overlap at all, but makes the plot lines roughly meet. Unsatisfactory, and Bowen should be excluded. The net effect on the Queensland and Australian trends is negligible (0.01 C).
Let’s look at Dr Jones’ assertion for the whole of Australia.
“…a near zero impact on the all Australian temperature …”
WRONG.
We can look at the record in a number of ways- here is the graph of the average raw and adjusted temperatures for all 100 stations. The discrepancy is obvious. 
That’s 0.6 degrees C / 100 years for the raw data. The adjusted trend is 0.85.
Before anyone complains that anomalies give you a more accurate picture of trends across a large region, I also calculated anomalies from the 1961-1990 mean for the all Australian means (0.6 raw to 0.85 HQ increase)
and for all 100 stations (slightly different result): (0.6 raw to 0.9- 50%)
But the figure BOM publishes is 1.0C- that’s a two-thirds increase!
We can also look at the average adjustment for each station: + 0.23 degrees Celsius. (The table of all 100 stations is too large to include).
Or we can find the median adjustment (+ 0.275 C), and the range of adjustments:
So much for “these tend to be equally positive and negative across the network”.
We can also look at the “quality” of the High Quality stations.
Urban vs Non-urban:
“Please note: Stations classified as urban are excluded from the Australian annual temperature timeseries and trend map analyses. Urban stations have some urban influence during part or all of their record.” (http://www.bom.gov.au/cgi-bin/climate/hqsites/site_networks.cgi?variable=meanT&period=annual&state=aus)
In Part 1 I showed how 3 Queensland sites listed as urban by Torok and Nicholls (1996) are now non-urban. Della-Marta et al resurrected a number of others in other states.
The full list is: Cairns AMO, Rockhampton AMO, Gladstone MO, Port Hedland AMO, Roebourne, Geraldton AMO, Albany AMO, Alice Springs AMO, Strathalbyn, Mount Gambier AMO, Richmond AMO, Mildura AMO, East Sale AMO, Cashmore Airport, Launceston Airport.
15% of the network is comprised of sites that BOM is at pains to assure us are not used to create the climate record.
Long records:
“… the number of stations is much smaller if only stations currently operating and with at least 80 years of data are considered. To increase the number of long- term stations available, previously unused data were digitised and a number of stations were combined to create composite records… all stations in the dataset (were) open by 1915.” (Torok and Nicholls)
Torok wanted 80 years of data: Della-Marta et al and BOM have settled for much less. There are six stations with no data before 1930 (80 years ago), but BOM has included these. Some are truly dreadful: Woomera- 1950; Giles- 1957; Newman- 1966.
As well, many of the sites have large slabs of data missing, with the HQ record showing “estimates” to fill in the missing years.
Here is a graph of the number of stations with data available for each year.
Note that only 70% of raw data is available for 1910; 90% by 1930; another drop from 1945 to 1960; and the huge drop off in HQ data this decade!
Data comparison:
“Generally, comparison observations for longer than five years were found to provide excellent comparison statistics between the old and new sites…… Comparisons longer than two years, and sometimes between one and two years, were also found to be useful if complete and of good quality… Poor quality comparisons lasting less than two years were generally found to be of limited use.” (Della-Marta et al, 2004)
Wouldn’t “excellent comparison statistics” be essential for such an important purpose? Apparently not. There are many sites with less than five years of overlapping data from nearby stations (up to 20 km apart). A number of sites have no overlap at all.
This results in enormous gaps in the temperature record. Here is the map of the High Quality network, with sites deleted if they are (a) listed as urban in 1996 (b) sites with less than 80 years of observations (c) sites with less than 5 years of comparative data overlap- or sometimes all of the above!
The sites left are concentrated in Eastern and South-Western Australia, with an enormous gap in the centre. Check the (admittedly very aprroximate) scale.
And finally…
Claims made in the State of the Climate report produced by BOM and CSIRO in March 2010.
Since 1960 the mean temperature in Australia has increased by about 0.7 °C . The long term trend in temperature is clear…
TRUE. But the raw data shows the mean temperature since 1910 has increased only 0.6 C.
Australian average temperatures are projected to rise by 0.6 to 1.5 ºC by 2030.
REALLY? That would require between 5 and 12 times the rate of warming seen in the raw temperature record, or between 3 and 7.5 times that shown by BOM’s published figures.
Much of Australia will be drier in coming decades
MAYBE NOT. See http://kenskingdom.wordpress.com/2010/03/20/political-science-101/
Our observations clearly demonstrate that climate change is real.
TRUE- that’s what climate does.
CSIRO and the Bureau of Meteorology will continue to provide observations and research so that Australia’s responses are underpinned by science of the highest quality.
“Highest quality”? REALLY?
Conclusion
This study shows a number of problems with the Australian High Quality Temperature Sites network, on which the official temperature analyses are based. Problems with the High Quality data include:
- It has been subjectively and manually adjusted.
- The methodology used is not uniformly followed, or else is not as described.
- Urban sites, sites with poor comparative data, and sites with short records have been included.
- Large quantities of data are not available, and have been filled in with estimates.
- The adjustments are not equally positive and negative, and have produced a major impact on the Australian temperature record.
- The adjustments produce a trend in mean temperatures that is roughly a quarter of a degree Celsius greater than the raw data does.
- The warming bias in the temperature trend is 41.67%, and in the anomaly trend is 50%.
- The trend published by BOM is 66.67% greater than that of the raw data.
The High Quality data does NOT give an accurate record of Australian temperatures over the last 100 years.
BOM has produced a climate record that can only be described as a guess.
The best we can say about Australian temperature trends over the last 100 years is “Temperatures have gone down and up where we have good enough records, but we don’t know enough.”
If Anthropogenic Global Warming is so certain, why the need to exaggerate?
It is most urgent and important that we have a full scientific investigation, completely independent of BOM, CSIRO, or the Department of Climate Change, into the official climate record of Australia.
I will ask Dr Jones for his response.
(Thanks to Lance for assistance with downloading data, and janama for his NSW work. Also Jo Nova for her encouragement.)
Pamela: I made those graphs. It’s a lot of work to make lots of 5-year trendlines! 🙂 I just did enough to illustrate the point I was making. I’m not sure that 5-year trendlines are particularly useful for agricultural purposes, unless you can predict years *in advance* what the ENSO and other such climate phenomena are going to do (which of course we cannot). Looking at 5-year trendlines from the past is interesting but rather academic for these purposes, wouldn’t you say?
Smokey said (July 28, 2010 at 8:49 am):
This chart strikes me as being rather bogus. It plots atmospheric CO2 against *current* global mean temperature anomaly, without accounting for the lag in the climate system, which is mainly due to the thermal inertia of the oceans. For example, today at ~390ppm CO2 we have seen ~0.8°C of warming above pre-industrial level, but there is still a net energy imbalance of ~0.5W/m², which means that even if CO2 never rose any further than 390ppm, we would still expect another ~0.4°C of warming (50% more than the current value) based on short-term climate sensitivity of 0.75°C/W/m². No-one disputes that this lag is present in the system. So, it seems to me that the predicted 1.62°C per doubling of CO2 based on observations is invalid.
Thanks Ken for your work, maybe it will make some of the scientists who are cooking this country’s historical temperature record think about how they and the dodgy science they represent will be viewed by the Australian people when the whole charade they have built up collapses as it certainly will.
They think they are well protected by both sides of the political spectrum who are playing things safe (just in case) and by the Australian Broadcasting Corporation (ABC) who have refused to allow dissenting scientific information to be debated on Prime time television and by their tight knit academia associations and total stranglehold on the government funding of climate science.
I think they will regret the damage they have done to the Australian people, the economic damage, the disruption of lifestyle, and the high cost that, they have personally imposed on ordinary Australians, by assisting the control agenda of socialist left academia, comfortable entrenched in feather bedded jobs and protected from feeling the effect of higher taxes, higher prices, loss of jobs, loss of opportunity and the ruination of the future job prospects of those children that they have helped indoctrinate with false expectations, the Eco Warriors of today, that will be the disenchanted of tomorrow once the full extent of the fraudulent manipulation is fully exposed.
I just hope that among our new politicians there will be some who insist on cleaning up Climate science by creating a Royal Commission or Judicial Inquiry with sufficient powers to compell them to disclose the full extent of what they have been wilfully promoting and wrongfully manipulating.
They should be careful of what they try and create and nervous about the backlash of public opinion once the rotten core of this scientific fraud is exposed. Unfortunately it may take a year or two, but it will surely happen.
I wish it was sooner, rather than later.
Looks like my last post hit the spam filter – maybe I was just too disgusted and let my feeling show!! I hate to see Australia go down the drain because of this stuff.
Icarus,
That chart shows two things: the model predictions, and reality.
You’re arguing for the model over reality. If you accepted reality, you would see that you have nothing to worry about. In fact, a 1°C rise in global temperature would be a major benefit to people, plants and animals. Warmer is better; cold kills.
And regarding your “time lag”, you might as well accept the fact that the rise in temperature is the result of the planet’s emergence from the Little Ice Age. CO2 outgases from the oceans as they naturally warm.
Smokey:
The reality is that it takes a long time to warm up 332 million cubic miles of ocean. I think you’d have to agree with that – it’s basic physics. It’s not a climate model telling us that. Your cited chart isn’t a valid representation of how much warming corresponds to a particular atmospheric concentration of CO2, because it doesn’t take into account the inertia of the climate system. It’s not measuring warming at equilibrium. Agreed?
As for the ice age argument, warming needs a forcing – a net energy imbalance – and there isn’t one from this supposed ‘recovery from the little ice age’. The only reason the Earth continues to warm in response to atmospheric CO2 today is that it hasn’t reached equilibrium yet – there is still that imbalance of ~0.5W/m², accumulating heat in the climate system.
Nice good-natured comment from you though, discussing the facts rather than ranting, as some people have here. It’s appreciated.
Icarus (7:36 am):
“…The problem with that argument is that satellite-based global temperature series are almost exactly the same as the terrestrial series….”
Not quite right,
http://woodfortrees.org/plot/gistemp/from:1979/trend/plot/uah/trend/offset:0.2
Icarus (9:02 am):
“…The CET shows warming of ~0.27C per decade over the last 50 years. Not ‘slight…”
Eyeballing the entire CET record, most of the warming appears to be in the last 20 years,
http://www.junkscience.com/MSU_Temps/HadCET_an.html
Icarus says:
July 28, 2010 at 1:39 pm
“[…] reached equilibrium yet – there is still that imbalance of ~0.5W/m², […]”
So the AGW crowd is now crowing about a purported energy imbalance of 0.2 % of the mean solar insolation? And this shall do what? Cause a problem? Make global climate reach a tipping point from which she is not able to recover? Meanwhile insolation regularly varies by 90 W/m^2 from perihelion to aphelion.
http://en.wikipedia.org/wiki/Solar_constant#Solar_constant
And has done so through all ages.
Icarus, this is not a believable scare scenario.
Ken,
Well done.
1. How does the rate of warming for rural stations compare with urban stations ?
2. How does the rate of temperature change appear for only long term rural stations that are really “high quality” ie well sited ?
Christopher Hanley: The difference between the satellite and terrestrial series is minimal. The warming is unequivocal. Also I would disagree about the CET – it looks like consistent warming in the last 50 years.
Aynsley kellow- yep that would be great, I just tried to keep it simple and stick to BOM’s own criteria.
Anthony Holmes- most rural airports in Australia are very quiet, lonely, bare, windswept places- not bad at all. They all need to be checked physically though. Busy airports have the problems you mention.
Icarus- make the trend short enough and you can prove anything. Don’t like 100 years? Too bad.
Bob-FJ- They would have some distance weighted algorithm for a grid 16 degrees x 16 degrees centred on each point. Or they might guess. As others have noted, the south east of Australia has most stations and has warmed the least- AND HAS BEEN ADJUSTED THE MOST! Strange but true. Much of SE Australian inland’s raw data shows flat or cooling means.
Folks- I won’t be able to comment again until this arvo as I’m off to school and Education Queensland has blocked WUWT from schools. My site is still OK so comment there and I’ll reply when I can.
Ken
DirkH:
A change in globally averaged insolation of less than 1W/m² was enough to take the Earth into and out of the last ice age – a difference in global mean temperature of ~5°C. Also it’s not just a matter of what the energy imbalance is at any particular time, but also of how long it’s sustained. If we keep pumping more CO2 into the atmosphere, that energy imbalance can’t decline to zero, so warming will continue, dependent upon how much longer we keep raising atmospheric CO2.
Short-term climate sensitivity is ~3°C (that is, the Charney climate sensitivity with fast feedbacks only). Put another way, that’s ~0.75°C/W/m², so the ~1.6W/m² of CO2 forcing since the pre-industrial should yield about 1.2°C of global warming, of which we’ve seen about 0.8°C so far, with 0.4°C of warming still to come, subject mainly to the lag from the oceans, and determined by that remaining ~0.5W/m² of net energy imbalance. However… fast feedbacks contribute only about half of the warming over longer timescales, the rest being mainly due to changes in ice sheet area, vegetation cover and climate-induced greenhouse gases, so even if atmospheric CO2 stopped where it is now, we’d be looking at a long-term warming of over 2°C… and no-one seriously thinks we’re going to stop raising atmospheric CO2 in the very near future. There is still too much cheap coal to burn.
Considering that we’re only at about 0.8°C of warming and we’re already seeing the terminal decline of Arctic sea ice, disappearing glaciers, thawing permafrost, shifting climate zones, rising sea levels, invasive species and many other effects, I don’t think I want to see what >2°C does to us. How will people know what to grow if the climate keeps changing all the time?
Icarus says:
“…this supposed ‘recovery from the little ice age’.”
If you believe the LIA did not occur, you are either uneducated or deluded. There are copious eyewitness accounts of the extreme cold during the LIA from around the world [the painting shows Washington crossing the ice-filled Delaware in 1776]. The LIA was a global event — unlike the current natural Arctic ice variability, which is only regional.
And your “~3°C short term climate sensitivity” number is a fantasy. If not, explain for us the percentage of “forcing” caused by CO2, vs the percentage of natural warming since the LIA. You will be the first to show where the line is drawn.
There is still much debate over the climate’s sensitivity to CO2, from the rational [<1.0°C] to the fantastic [the UN/IPCC’s ridiculous 3 – 6°C]. Planet Earth herself makes it clear that the effect of CO2 on temperature is minimal.
You really need to get out of that RealClimate echo chamber more often. It is run by mendacious censoring prevaricators and populated by closed-minded people who like comfortable echo chambers. Stick around here and you’ll learn that the large increase in CO2 is almost entirely due to natural emissions as a result of the planet’s warming.
Rises in CO2 follow temperature rises on all time scales. Effect can not precede cause, therefore the fabulous story that a very minor trace gas can cause runaway global warming is only believed by the credulous.
I like to maintain a temperature comparison on my site at http://www.waclimate.net based on 32 locations in the western half of Australia with fairly consistent records dating to 1900 and earlier. I update it each month with the latest BOM data and when doing my update late last year I noticed the mean minimum and maximum temps had all been adjusted up by about half a degree from what had previously been on the BOM website for August 2009. e.g. with their initial data at the top as posted by BOM from September 1 to November 17, and their new adjusted data below:
Albany
9 16.2
9.4 16.6
Geraldton
9.5 20
10 20.5
Marble Bar
13.8 31.1
14.3 31.5
Perth
8.8 18.5
9.3 18.9
etc. I questioned the BoM on what happened and received this reply … “Thanks for pointing this problem out to us. Yes, there was a bug in the Daily Weather Observations (DWO) on the web, when the updated version replaced the old one around mid November. The program rounded temperatures to the nearest degree, resulting in mean maximum/minimum temperature being higher. The bug has been fixed since and the means for August 2009 on the web are corrected.”
The temps for all Western Australia locations in the BOM web database remain at the higher adjusted temperatures and I’m still not sure why they thanked me for pointing out the problem.
My independent, non peer reviewed, check it yourself comparison of temps at the 32 locations suggests the average min across Western Australia has increased by .8 C and the average max has increased by 1.31 C since the 19th century compared to the year to June 2010.
In the year to July 2009, a comparison with exactly the same 1800/1900 baseline showed the average min up by .31 C and the average max up by .64 C.
So for Western Australia, either the average min has leapt by about .5 degrees and the average max by almost .7 degrees in less than a year with extremely hot weather distorting the climate comparison … or inexplicable “bugs” raise questions about the validity of the BOM’s recent dataset as presented on the web.
Smokey:
Yeah, one might “learn” that, but it won’t be a correct learning.
The stoichiometry with oxygen reduction, the isotope signatures, the simple accounting of the amount of combusted fossil carbon with respect to CO2 flow rates into sinks, and the fact that the warming is post-contemporaneous with CO2 increase (rather than preceding CO2 increase by 800 years as many are fond of indicating), all demonstrate that you have the cart before the horse.
They do when the rise in CO2 is a reponse to the effects of warming resulting from other forcings.
However, the simple fact is that as a greenhouse gas, CO2 itself can also force temperature. You are telling only half of the story, and doing so does not make you correct, nor does it change the fact of the physics of greenhouse gas warming, and it certainly does not refute the contribution of CO2 as a cause for the modern warming.
On the matter of the Australian temperature record, perhaps some of the commenters here might like to explain why the fruit trees in my district have shown reductions in fruitset over the last 30 to 40 years, to the point that many orchards are being comlete;ly ripped out and replaced with varieties that require far fewer chilling hours. Perhaps they might like to explain why many spring-flowering species are flowering one to two weeks earlier – or even more – than they did in the 70s.
Perhaps they m ight like to explain why the number and the severity of frost-nights in my area has decreased from dozens each winter several decades ago, to less than a sinlge dozen each year over the last ten years. Perhaps they might like to explain why the snowing-in of people living in valley on the other side of the ridge to me, an event that used to occur annually on at least two or three days, no longer occurs – and in fact they might like to explain why it is now rare to experience any snow in the valley or on my side, let alone the 18 inches or more which used to be a regular occurence.
Perhaps the commenters here can explain why the salmon industry in our waters, which in previous decades had no issue at all with water temperatures rising, is now facing annual summer increases that threaten the very survival of the stocks. Perhaps they might explain why the industry is seeking heat-tolerant species to replace the salmon, should the water warm any further and render the current industry non-viable. Perhaps they might like to explain the presence of tropical and warm-temperate fish species in our waters each summer, that were never observed three or four decades ago.
I’d be most interested to hear their explanations for each of these phenomena.
Hey there Bernard J, another RealClimate refugee I see.
You avoided responding to my request to explain for us the percentage of “forcing” caused by CO2, vs the percentage of natural warming since the LIA.
What exactly are these vague other “forcings”? The effect of CO2 is negligible, as I cited in my post up thread. So what are these other so-called ‘forcings’ that are [very moderately] raising the temperature? And how can you separate them [if they all even exist] from the planet’s natural warming from the LIA?
Where is your runaway global warming? Right around the corner — as always?
JohnH said (July 28, 2010 at 6:53 am):
when you look at areas with long well documented temp records and large populations you see no or slight warming eg Central England, Northern Ireland.
The CET shows warming of ~0.27C per decade over the last 50 years. Not ‘slight’.
This just confirms what I have said, if you look at the full temp record for CET this rate of warming over the last 50 years is nothing unusual and has been repeated before and current temps are not high.
Dr A Burns said:
1. How does the rate of warming for rural stations compare with urban stations ?
2. How does the rate of temperature change appear for only long term rural stations that are really “high quality” ie well sited ?
1: No idea. Do you mean the urban stations BOM identifies and doesn’t use, or the 15 they still use? Haven’t looked at either but will sometime in the future.
2: Why bother? The result could be increased, decreased, or about the same, but essentially meaningless. Have a look at the second map showing the stations that are long term, rural, and with decent overlaps. There are 50. I don’t know how many of them have siting issues. BOM says 100 should be enough to give a reasonable climate picture for Australia. We are talking about 50 sites to cover the whole continent. There are huge areas (millions of square kilometres) without any good sites. You could look at smaller regions e.g. eastern Australia but not for Australia as a whole. I could do it but it would contribute nothing.
Ken
Hey, CAGW fools. There’s this cyclical nuclear furnace, about which we’re orbiting, that just went through what is called a “solar maximum”. None of your comments seem to ackowledge this “inconvenient” fact, and you seem to be all worked up over an increase in plant food that appears beneficial to the continued survival of life as we know it. But…but…but we mere riff-raff can’t presume to challenge your superior intellect. How could we?! Well, we can and we will and the truth will out through the free exchange of ideas (intellectual property). Or is this concept anathema to you?
Icarus says:
July 28, 2010 at 3:16 pm
“Christopher Hanley: The difference between the satellite and terrestrial series is minimal. ”
Only because the satellite data has recently been deliberately cooked to make it match up. It was cooked because the real satellite data was showing unmistakeable signs of divergence from the previously cooked terrestrial series.
Christopher Hanley says:
“Not quite right,
http://woodfortrees.org/plot/gistemp/from:1979/trend/plot/uah/trend/offset:0.2”
What’s the difference between that and this one?
http://woodfortrees.org/plot/gistemp/from:1979/trend/plot/rss/trend/offset:0.2
“Bernard J. says:
July 28, 2010 at 9:13 pm ”
Dunno, where do you live? All I can tell you is that this winter in the inner west of Sydney has been the coldest I can recall, regularly 2c or more below usualy for this time of year. Even ex-pats returning to Australia from the UK, and last winter in the UK was the colderst in 30 years or more, are finding this Australian, southern hemisphere, winter cold.
With the salmon thing, there are MANY factors that affect their spawning, one of which is temperature.
********
Icarus says:
July 28, 2010 at 7:36 am
The problem with that argument is that satellite-based global temperature series are almost exactly the same as the terrestrial series.
********
The problem is that going by basic greenhouse theory, the mid-tropospheric sat temp trend should be about 1.2x greater than the surface trend (up or down). By this, if the sat trend is +.8 C/century, the surface trend should be only +.67 C/century.
Patrick Davis says:
(July 29, 2010 at 6:59 am)
I’m not referring to salmon spawning. Salmon in Australia are always artificially bred, and raised to fingerling-size in cool, fresh water well within their optimal temperature envelopes.
I am referring to the day-to-day physiological response of adult salmon in marine farms, when ambient summer water temperatures rise close to the tolerable limit. Twenty or thirty years ago salmon were able to be raised to salable size with naver a single individual lost to excessive warmth: these days many many fish are routinely lost to warm water, or the growth and health of whole nets (= tens of thousands of fish) is so compromised as to make the viability of farms uncertain.
Where is this warmth, and the warmth that is altering our seasons, coming from?
Bernard J,
Are you not aware that the increase in global temperature is only about 0.7°C over the past century and a half [not the past 20 – 30 years]?
Any anomalous local warming is due to natural climate changes — the same source that makes other regions colder than they have been. It’s silly to believe that a 0.7° change in temperature is going to kill off the world’s farmed salmon population.
You need to show us evidence, from a credible source, showing that farm raised salmon are dying throughout the world from too much heat. Can you provide a reliable citation to back up your story? It looks like what you’re claiming is the usual cherry-picked alarmism. In your case, it may be an entirely invented scare.
Finally, to answer your question about where the [very mild] warmth came from, it is due to the planet’s emergence from the Little Ice Age.