Holocene, historic and recent global temperatures from temperature proxies.
Guest post by: Frank Lansner, civil engineer, biotechnology
NOTE: Link to PDF of this article is HERE
In the climate debate, the temperatures of the past are used to determine if the present temperatures are unique and alarming. Any viewpoint can be supported by choosing specific science papers as reference
This paper is one of many attempts to give a realistic overview of the actual messages we get from the temperature proxies.
(“Temperature proxy”: Past temperatures reconstructed from samples using a row of techniques.
The “Spaghetti graphs” in the following gives an impression of the huge variability among the datasets. The essence of each graphic is the major trends. To enable display of multiple data series it was often necessary to interpolate temperature values to the specific years used in graphics.
To avoid most calibration problems, I have set specific years to zero for the different graphs I chose a year where practically all graphs has data, and no further calibration needed. In few cases I have calibrated from 1980-1990-2000 using UAH trend of approx. +0,1K/decade.)
Recent temperature proxies – 120 years
Fig 1: 10 multi proxies shown for the 20´th century. In addition 14 temperature proxy datasets. The black curve shows average of the 14 datasets as 1 multi proxy. This multi proxy + the 10 of the most used bigger multi-proxy series is the basis for the WHITE graph: “Average of 11 multi proxies”.
The temperature proxies does not show strong net warming since around 1940. In fact, proxy data does not show any warming since 1940. This is no news, it has been recognised for example here:
http://www.ldeo.columbia.edu/res/fac/trl/downloads/Publications/divergence2007.pdf
The authors call the missing global warming in proxies for “The Divergence problem”. And they try to give reasons for this problem using characteristics of trees. But since other proxies than using tree ring proxies also indicates no global warming after around 1940, the problem seems not related with tree rings measurements.
“The divergence problem”:
Fig 2: The “divergence problem”.
The “All China” multi proxy: A reliable work where 8 regions of China where studied and then yield the final China multi proxy temperature line. The “All USA”, NOAA raw, is the official measured USA temperatures minus the official correction, that is, the raw USA temperature dataset. I find it stunning how close All-China and All-USA matches each other, see fig 2! (- a dataset of measured temperature compared to a dataset of proxies). And unlike GISS 2009, the Northern Hemisphere temperature set of 1976 supports the raw trends of US and China. Several of the multi proxy series have been smoothed with a “50 year weighted Gaussian filter” etc. and therefore any bigger dive around 1970 could not be seen in the multi proxy graph.
We see a divergence after 1950 between:
- GISS 2009 vs. Average of the multi proxies, that is, the temperature evidence in the ground and trees.
- GISS 2009 vs. USA, CHINA and NH temperatures
- GISS 2009 vs. Solar activity.
So, at least when comparing with mostly raw datasets, the GISS 2009 dataset could seem to be the source of “the divergence problem” – “the outlier”. Problems for the GISS data set might be incorrect adjustments, problems with UHI and poor measuring sites, see www.surfacestations.org!!
The “divergence problem” also seems to vanish when using satellite data (UAH/RSS) in stead of GISS data:
Fig 3: A: Briffa´s 2001 illustration of tree ring proxies combined with the GISS dataset as “Observations” (as the adjusted GISS temperatures are called). B: Same, however this time “Observations” are raw satellite data UAH from 1980 – 2000 with a slope of 0,1K/decade.
There is no divergence problem when using satellite temperature data as “Observations”. We now have total compliance between proxy data and modern temperature measurements stating: No net warming since around 1940-50.
Historic temperature proxies – 1200 years
For this analysis 33 data sets was used. The first that strikes you when working with historic temperature proxies is the apparent chaos of data. However, after keying in 6-8 data sets the well known features “Middle age warm period” and “The little Ice Age” becomes clear. Keying in the rest of datasets doesn’t change much.
First, take a good look at the period 1900 to 2000..
Notice how these 33 datasets confirms the trends from fig 1, the recent temperature proxies. We can conclude that we have a good ability to reproduce the result quite accurate with quite different datasets, and thus, neither of the graphs ( fig 1 and fig 4) are likely to reflect “random” results. All data evidence used in fig 1. + fig 4. actually suggests that today’s temperatures resemble the temperatures of 1940-50. Yes, a divergence problem for the temperature data from GISS and Hadcrut.
Fig 4: Historic temperature proxy data. Practically all methods and regions of the globe are represented.
6 of the data sets originate from tree ring data.
We see the Medieval Warm Period apparently ongoing already in year 800 and goes on for 5-600 years. First around year 1400 the Little Ice Age really takes over. It was around year 1400 the Vikings left the freezing Greenland.
From year 800 to year 1300 temperatures appears around 0,3 K higher than today. And from around year 1400 to 1900 temperatures appears to be are around 0,4 K lower than today. A difference from MWP to LIA of 0,7 K in average globally. (Max difference approx 1,1 K),
We will return to these historic data later, but lets first take a look even further back in time.
Holocene temperature proxies – 12000 years
For this analysis 29 long datasets where used. All graphs are calibrated to zero for year 1000.
First focus on years 800 to 2000…
Once again we see a reproduced trend between 2 different data sets. And again, the accuracy is nice. The MWP here appears almost 0,8 K degrees celcius warmer than the LIA, very close to what we saw it on fig 4, the historic data 0,7K. This once again confirms the impressing usefulness of data despite the chaotic and random appearance. There is however a tiny difference between the 2 graphs, around 0,1K. But it should be noted, that for the Holocene temperatures, no tree ring data was used. According to Loehle 2007, tree ring data tends to suppress the MWP somewhat. This we will return to.
Fig 5: Holocene temperature data.
The data point for year 2000 are based on too few datasets to be really trustworthy. Therefore I have inserted the red star where I use the value of todays temperature taken from fig 4, historic temperatures. By doing so, temperature for year 2000 got 0,2 K warmer than from Holocene data.
Fig 5 also shows that the whole debate about MWP is irrelevant. Imagine there was no MWP. Practically ALL of the Holocene period the eath appears to be between 0,5 and 1,5 K warmer than today. The little ice age does resemble a mini ice age or at least it appears to be the coldest period in over 10.000 years.
Finally, the overall picture from the graph is an almost perfect mathematical curve that tops around 5-6000 years ago. These Data tells the story quite clear: We are on a down trend in temperatures globally, we should not fear warmth by now. How much lower can the temperatures on earth go before we reach a tipping point to much colder temperatures at earth?
Medieval warm period
Arguments against the MWP often focus on the “fact” that the warmer temperatures from that period are a phenomenon exclusively to have appeared on the northern hemisphere.
Fortunately, the results from fig 4 and fig 5 shows an excellent match for the period year 800 to year 2000. It thus makes very good sense to combine the datasets and then obtain a better data foundation to analyse the MWP.
Datasets from fig 4 and fig 5 combined, a northern/southern hemisphere display of the Medieval Warm Period:
Fig 6: Historic temperatures, North and south hemispheres separated. Let’s first see what the graph actually says, very roughly:
NH MWP, 42 datasets:
Ongoing in year 800, temperatures mostly 0,3-0,4 K higher than today.
The temperature creeps below today’s level and ends around year 1300.
SH MWP, 13 datasets:
Ongoing in year 800, temperatures mostly 0,2-0,3 K higher than today.
The temperature creeps below today’s level and ends around year 1350.
Northern hemisphere is still much better represented than the southern hemisphere, so what can we conclude on this ground? Can we conclude anything?
On this ground I find it safe to accept the NH MWP approximately as described above.
To accept that globally there where no MWP, we will have to accept the following:
The 2 hemispheres have the ability to maintain a quite different temperature development for at least 500 years and did so from year 800 to year 1300.
What can we demand to accept this idea? We can demand solid evidence.
Anyone claiming the above must present solid evidence for a MEDIEVAL COLD PERIOD on the southern hemisphere.
IF data showed that the southern hemisphere had a MCP where temperatures for 500 years was 0,3-0,4 degrees colder than today, would this “kill” the MWP? Certainly not. Because, then we would have had 500 years with global temperatures just like today globally… – In that case, certainly no reason to be alarmed about the temperatures today.
No, if today’s temperatures should be alarmingly warm, the S. hemisphere temperature should show a very strong MCP at least 0,4 degrees colder than today in the 500 year period.
Is there ANY indication of a 500-year strong MCP in the southern hemisphere indicated in the data above? No, certainly not. There are not that many SH data, but still, there is not the slightest indication of a strong MCP on the S. Hemisphere.
Until the strong 500 year long MCP on SH has been proven, there is nothing that shakes the acceptance of a global MWP with temperatures resembling or higher than today’s temperatures.
I believe a massive use of tree ring graphs exclusively might show a strong southern MCP. In this case, the idea that there is no MWP globally is dependent on only on one specific method of making temperature proxies, tree rings. Tree rings are 1 of at least 20 different methods to measure temperatures of the past. As such, they should never dominate the measurements.
The South pole and MWP:
While examining temperature proxies, I found some odd results:
Fig 7: -A stunning mismatch between 2 Antarctic data series.
Not only are they both from Antarctica, but they are both from near the south pole. The well known “MWP-signature” has found its way not only to the Southern hemisphere, but to the south pole. But in the near by Vostok location, for many centuries, there has been absolutely no sign of the MWP? Obviously this is absurd, so at least one of the two results is not accurate.
The black graph (from “Remote Plateau”) has a resolution of 1 – 3 years per sample, excellent. The blue graph (vostok) has approx 23 years between data points. Both series should be considered fine quality then.
How likely is it, that the “MWP/LIA-signature” has come up in “Remote plateau” (black graph) data by a coincidence? When it has also been spotted many other places on the SH? See fig 6: The Vostok data has a dotted red line. How well does vostok data then fit the rest of the Southern hemisphere data?
The use of vostok data also moves the SH temperature profile away from the NH average.
Tree rings
If the MWP only disappears using one a specific measuring method, the idea as well as the method is invalid.
Proxy temperature data from tree rings are easy to get, but the quality?
Craig Loehle: “There are reasons to believe that tree ring data may not capture long-term climate changes”.
Indeed. A good warm year will obviously help a tree growing, but decades of increasing temperatures could affect the whole area so for example more trees might be able to survive, the root nets would only be able to grow to some extend for other trees etc.
Example: Imagine that a warming after decades is accompanied by 10% more trees surviving in an area and eventually demands their “place in the sun”. By measuring tree rings for an individual tree you are not measuring the overall tree growth of the area. And measuring 10.000 trees does not change anything as all trees would have the same problem. Measuring tree pollen or isotopes etc in sediment cores avoids these problems and it makes me wonder how come so much energy has been used for tree ring analyses.
Selective adjustments?
Many kinds of adjustments are used in connection with climate results. But one adjustment I haven’t heard of is the down-adjustment of recent temperatures from temperature proxy data due to CO2-induced extra growth. If the CO2 level is indeed extraordinary high, then it is a fact that plants grow markedly more. And they grow at higher altitude etc.
Here is an impressing overview of plant response to extra CO2 in the atmosphere:
http://www.co2science.org/data/plant_growth/dry/dry_subject_p.php
I have chosen the letter P for the link since several tree ring analysis are made for pine trees. Check the responses for pine trees when adding extra CO2.
Therefore any temperature proxy based on plant growth should be adjusted down in times of high CO2. Otherwise you will measure CO2 and not heat. But this obvious kind of adjustment seems not to happen? Or? Can it really be, that the crew of alarmists so happy for adjusting for all kinds of tiny issues, simply don’t adjust when there is a really good reason to do so?
Fig 8: Historic temperature proxy data with focus on tree ring-method. In the analyses I have used, it turned out that 7 of 55 datasets where from tree rings. On this figure, these 7 datasets actually does seem to differ in trend from all the rest. The 7 tree ring datasets suggests no MWP, in fact, they suggest that the MWP was 0,3-0,4 K COLDER than today’s temperatures. Quite the opposite result than the majority of datasets concerning MWP.
On might say that these 7 datasets are too little a basis for any conclusion, and therefore I have included a bigger tree ring multi proxi, “Esper et al 2002” and the trend from the 7 tree ring datasets are confirmed:
Unlike all other methods, tree rings shows no warm MWP.
Example, the European Alps:
Fig 9: Here from fig 4, we have 2 different temperatures in the same area, the European Alps.
Quite like Antarctica, we have 2 datasets, one showing the well known “MWP/LIA-signature” and one not showing this. Both cannot be correct, so we know that at least one of the datasets is faulty.
In addition, these measurements where taken in the middle of Europe where we have an overwhelming amount of non-tree temperature proxy datasets confirming a very warm MWP.
Therefore, if the tree ring method was useful, we definitely should see a warm MWP from tree ring data in Europe. But we don’t. And unless all the other temperature proxy methods just shows a very warm MWP in Europe by coincidence, the tree ring method does appear to be the faulty method.
The tree graph appears flat compared to the other methods (- a “yummy” to use if you want to produce a hockey stick), but we are not here to produce a hockey stick, we seek the temperatures of the past.
Now it becomes relevant to examine jus non-tree temperature proxies (As Loehle concluded) for better accuracy:
Fig 10: The Historic temperature proxy trend based on 27 non tree ring proxies show a slightly warmer MWP than when including tree rings, fig 4. The average temperature for year 800-1400 is approx 0,4 K warmer than today, and the years 1400-1900 is around 0,4 K colder than today. So the non tree historic temperatures now gives a MWP/LIA difference of 0,8 K like the (non tree) Holocene temperatures, fig 5.
We even see “peaks” in the MWP up to 0,6K warmer than today, and now 1950 actually appears slightly warmer than today.
Fig 11: Briffa’s 2001 all tree ring proxy data, compared with non tree ring data.
First of all, I have every respect for the huge work done using tree rings. There are indeed many sources to errors (like the idea about different SH/NH temperature development etc.) – but despite all, this graph speaks a very clear language.
Here we see the 27 datasets of non-tree rings, together with the well known tree ring graphs.
It becomes clear, that the non tree rings world wide – THICK BLUE CURVE – matches extremely well in the 20’th century and all the way back to year 1450. Then exactly as the MWP starts, the tree rings and the non
tree rings simply “looses contact”.
What ever the reason for the differences between tree ring or non tree ring temperature proxies,
it becomes evident, that choosing tree rings or not is the same as choosing a MWP or not.
.
One partly explanation for this huge mismatch could be CO2. If indeed the CO2 concentration today is a lot higher in the atmosphere than it was in the MWP, then trees simply grows faster than in the MWP, apparently even though temperatures are not higher.
S
Conclusion:
– Its way too early to consider the MWP gone. There is a lot of scientific work to be done before any such conclusion has any weight. MWP disappears when using tree ring data.
– In this writing we see that 48 non tree ring temperature proxies combined shows a MWP around 0,4 K warmer than today, lasting at least 500 years.
– Besides the MWP discussion: 80-90% of the Holocene period (last 10-12.000 years) has been warmer than today. The last 6000 years, the general temperature trend has been steady cooling. The temperature levels in the Little Ice Age were the lowest in the Holocene period.
I find it relevant to study the consequences of further cooling.
– Except for strongly adjusted temperature data, there is compliance between recent temperatures measured from satellites, evidence from tree-proxies, evidence from non-tree-proxies and more showing that: It does not appear warmer today than around 1940-50.
This is in compliance with solar activity in the 20’th century.
This does not suggest a warming effect of CO2 in the atmosphere.
ome of the non-tree-ring measurement methods includes Be, O and C isotopes etc, that in some cases are more independent of changing tree growth or the like. These methods would be preferable if we wanted to clear CO2-induced errors on temperature measurements.
| 1) Alley, R.B., 2000 | The Younger Dryas cold interval as viewed from central Greenland GISP2 |
| 2) Andersen et al., 2004 | A high unstable Holocene climate in the subpolar North Atlantic: evidence from diatoms |
| 3) Barron et al., 2003 | High-resolution climatic evolution of coastal northern California during the past 16,000 years. |
| 4) Biondi et al., 1999 | July temperatures during the second millenium reconstructed from Idaho tree rings. |
| 5) Büntgen et al., 2005 | PYR – MXD Pyrenees reconstruction |
| 6) Büntgen et al., 2006 | Summer Temperature Variations in the European Alps, A.D. 755-2004 |
| 7) Büntgen et al., 2007 | Growth responses to climate in a multi-species tree-ring network in the Western Carpathian Tatra Mountains, Poland and Slovakia |
| 8) Cook, E.R., et al. 1998 | Tasmania Temperature Reconstruction |
| 9) D. Dahl-Jensen et al., 1998 | Past Temperatures Directly from the Greenland Ice Sheet |
| 10) D’Arrigo et al., 2006 | Alpine Spruce Composite tree-ring record – living and historical material |
| 11) DeMenocal and Ortiz 2000 | Coherent High- and Low-Latitude Climate Variability During the Holocene Warm Period |
| 12) Fang Jin-qix 1990 | Climate changes during the holocene and their impact on hydrological systems |
| 13) Filippi, M.L. et al., 1999 | Climatic and anthropogenic influence on the stable isotope record from bulk carbonates and ostracodes in Lake Neuchatel, Switzerland, during the last two millennia |
| 14) Ge, Q., et al 2003 | Winter half-year temperature reconstruction for the middle and lower reaches of the Yellow River and Yangtze River, China, during the past 2000 years |
| 15) Glen MacDonald 1996 (PALE) | Paleoenvironmental Time Series from Postglacial Lake Basins on Kola Peninsula, Russia |
| 16) Goni., 2004 | Generation, transport, and preservation of the alkenone-based U37K’ sea surface temperature index in the water column and sediments of the Cariaco Basin (Venezuela). Global Biogeochemical Cycles 18: 10.1029/2003GB002132. |
| 17) Grudd, H. 2005 | Tornestrask updated reconstruction. Tornetrask tree-ring width and density AD 500-2004: a test of climatic sensitivity and a new 1500-year reconstruction of north Fennoscandian summers. |
| 18) Hammerlund et al., 2004 | Diatom inferred SST (August) variations in core MD95-2011, Voering plateau |
| 19) Hendy and Kennett, 2000 | SST estimates from planktonic foraminiferalassembl ages |
| 20) Holmgren., et al. 2001. | A preliminary 3000-year regional temperature reconstruction for South Africa |
| 21) Hui Jiang et al., 2005 | Evidence for solar forcing of sea-surface temperature on the North Icelandic Shelf during the late Holocene |
| 22) Isaksson., et al., 2006 | Austfonna ice core – Svalbard |
| 23) J. R. Petit et al., 2000 | Historical Isotopic Temperature Record from the Vostok Ice Core |
| 24) K. Antonsson,. et al. 2008 | Anticyclonic atmospheric circulation as an analogue for the warm and dry mid-Holocene summer climate in central Scandinavia |
| 25) Kaiser, J., et al 2005 | A 70-kyr sea surface temperature record off southern Chile |
| 26) KERR et al., 2008 | Ghiacciai e cambiamenti climatici durante l’ultimo secolo nella regione Aoraki/Mt Cook, Nuova Zelanda |
| 27) Kim et al., 2002 | Alkenone-base sea surface temperature record (8C) for core from the Benguela Current |
| 28) Koutavas et al., 2005 | Tropical Pacific SST gradients since the LGM in relation to the ITCZ |
| 29) Linderholm et al., 2005 | Summer temperature variability in central Scandinavia during the last 3600 years. |
| 30) Liu, Z., 2006 | Alkenone-based reconstruction of late-Holocene surface temperature and salinity changes in Lake Qinghai, China |
| 31) Lloyd D. Keigwin | The Little Ice Age and Medieval Warm Period in the Sargasso Sea |
| 32) M.R. Besonen., 2008 | A record of climate over the last millennium based on varved lake sediments from the Canadian High Arctic |
| 33) Mangini, A.et al., 2005 | Reconstruction of temperature in the Central Alps during the past 2000 yr from a δ18O stalagmite record. |
| 34) Mc Greggor et al., 2007 | Rapid 20th-century increase in coastal upwelling off northwest Africa revealed by high-resolution marine sediment cores |
| 35) Meixun Zhao et al., 2006 | A millennial-scale U37 K sea-surface temperature record from the South China Sea (8°N) over the last 150 kyr: Monsoon and sea-level influence |
| 36) Moore, J.J., et al., 2003 | Baffin Island 1250 Year Summer Temperature Reconstruction, |
| 37) Mosley-Thomson 1996 | Holocene climate changes recorded in an east Antarctica ice core |
| 38) Nesjea et al., 2004 | Holocene millennial-scale summer temperature variability inferred from sediment parameters in a non-glacial mountain lake: Danntjørn,Jotunheimen, central southern Norway |
| 39) Newton et al., 2006 | Climate and hydrographic variability in the Indo-Pacific Warm Pool during the last millennium. Geophysical Research Letters 33: 10.1029/2006GL027234 |
| 40) Nyberg, J., et al., 2002, | Northeastern Caribbean Late Holocene Sea Surface Temperature Reconstruction |
| 41) Powers, L.A., et al 2005 | Lake Malawi TEX86 Surface Temperature Reconstruction |
| 42) Sachs et al., 2007 | Cooling of Northwest Atlantic slope waters during the Holocene |
| 43) Sallinger et al., 1988 | The nature of New Zealand’s atmosphere and climate |
| 44) Salzer, M.W. and K.F. Kipfmueller. 2005 | Southern Colorado Plateau Temperature and Precipitation Reconstructions |
| 45) Selvaraj et al., 2007 | Holocene East Asian monsoon variability: Links to solar and tropical Pacific forcing |
| 46) Seppa et al., 2003 | Holocene annual mean temperature changes in Estonia and their relationship to solar insolation and atmospheric circulation patterns |
| 47) Seppa et al., 2005 | Diatom inferred SST (August) variations in core MD95-2011, Voering plateau |
| 48) Societa Geologica Italiana 2007 | Variabilità naturale del clima nell’Olocene ed in tempi storici:un approccio geologico |
| 49) Stott et al., 2004 | Climate/Ocean History of the Western Tropical Pacific |
| 49) Stott et al., 2004 MD2176 | Decline of surface temperature and salinity in the western tropical Pacific Ocean in the Holocene epoch |
| 49) Stott et al., 2004 MD2181 | Decline of surface temperature and salinity in the western tropical Pacific Ocean in the Holocene epoch |
| 49) Stott, et al., 2004 MD2170 | Decline of surface temperature and salinity in the western tropical Pacific Ocean in the Holocene epoch |
| 50) Tan, M., et al., 2003 | 2650-Year Beijing Stalagmite Layer Thickness and Temperature Reconstruction |
| 51) Tarasov., et al 2009 | Late Glacial and Holocene changes in vegetation cover and climate in southern Siberia derived from a 15 kyr long pollen record from Lake Kotokel |
| 52) Tyson., et al 2000 | The Little Ice Age and medieval warming in South Africa. |
| 53) V. RULL., 1996 | PALAEOCLIMATOLOGY AND SEA-LEVEL HISTORY IN VENEZUELA. |
| 54) Wang et al., 2000 | Twentieth-century warming in the context of the holocene |
| 55) Wilson, A.T., et al. 1979 | Short-term climate change and New Zealand temperatures during the last millennium |
| 56) Zabenskie, S. and Gajewski, K | Post-glacial climatic change on Boothia Peninsula, Nunavut, Canada. Quaternary Research 68: 261-270. |
| 57) Zinke et al., 2001 | Evidence for the climate during the Late Maunder minimum… |
| 58) Devi, et al ., 2008 | Expanding forests and changing growth forms of Siberian larch at the Polar Urals treeline during the 20th century |
| 59) Kim et al., 2006 | Age and alkenone-derived Holocene sea-surface temperature records of sediment core SSDP-102 |
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Quick note. Interesting data west Australia via http://joannenova.com.au/2009/04/03/global-warming-a-classic-case-of-alarmism/ :
A brief look at the inland low population stations show no hockey sticks. No slope, either. PDO immune? CO2 immune?
Absolutely brilliant work, Frank. Thank you.
This paper should be required reading for every college student, every faculty member, every high school science class, every teacher, every member of congress, every journalist and every employee of NASA, NOAA, CPC, and so on….
About three times a week I run through First Landing State Park, at the “end” of my corner of the world, situated at the confluence of the mighty Chesapeake Bay and the Atlantic Ocean [called First Landing because that is where the Jamestown Settlers landed in 1607–ironically in one of the years that some say was the coldest in the LIA–and where many of the Jamestown settlers starved through a difficult winter].
Even more ironic are the “hills” in the park. This is the flat coastal plain so there should be no hills as there is no tectonic action around to be found.
On the “hills” are an interesting mix of northern hardwoods such as beech and maple, and subtropical loblolly pines and spanish moss.
This park is an extraordinary clash of zones which show prima facie evidence of the ebbs and flows of Earth’s climate both in the SHORT RUN [multidecadal] and in the LONG RUN:
In the warm AMO and PDO combination…the good ole’ south Scarlet O’Hara “well shuck-my-corn ya’ll and put some cheese in my grits” plantation advance of spanish moss, tupelo trees, and copperhead snakes reigns supreme.
When those oscillations shift negative, the beech, blueberries, and sugar maples take over on the “hills.”
Now in the LONGER RUN….look back into the earlier Holocene, just about 5,000 years ago, and we see these “hills” are not hills at all.
They are former waterfront sand dunes…when sea levels were higher around than they are now.
This all occurred in the Biblical times before there were enough humans to produce the CO2 to cause the supposed “warming”……which in the grand 10,000 year scheme of things…is not showing warming at all.
Thanks again Frank…..this work is another brilliant nail in the coffin for the new world religion of the International Church of the A.G.W.
Speaking of coffins….every time when I think of that first Jamestown winter in 1607 where people froze and starved to death…I shudder to think that the current world figures and organizations….Obama, Holdren, Hansen, NASA, the UK Met, et al….seem to be JUST as ill-prepared for such a turn in the climate if that is the direction things are going….
Chris
Norfolk, VA, USA
CORRECTION:
“They are former waterfront sand dunes…when sea levels were higher than they are now.”
Dear Frank, a heartfelt thank you for the second day’s reading of this magnificent synthesis. While I respect those who suggest that you break up the conclusions into a number of articles, I emphatically disagree. The greatness of your effort is that you are responding to every argument frontwards and backwards, leftwards and rightwards, through the conclusions of those who have spent so much of their lives in the dogged details of research.
There is no place to hide once one has read your article. It is most assertive, no, aggressive, for science and the truth. It places the accountability for deception right where it belongs — by comparing research and pseudo-research.
Go for it. It deserves a place in the most prestigious publication that will accept it. Or, perhaps prestige is not as important as a combination of prestige and wide readership.
Hey sod, where is the “massive effect on flora and fauna” from the Modern Warm Period? Your premise seems to be pretty wrong to me.
Comments above about someone saying we are adding some large amount of CO2 by mass into the atmosphere-sounds dramatic when you put it that way, doesn’t it? Except there are 3.5 trillion tons of CO2 in the atmosphere already (the amount of carbon is a different story, but I’d wager it’s higher).
As someone who is red green colorblind (approximately 10% of the population has a color vision irregularity), I would strongly second that recommendation, and extend it to every presentation intended for large audiences made by any of the readers of this blog.
One of the most difficult problems for the people with atypical color vision, is to sort out similar gray tone pastel, or dark subdued color traces. If similar colors are placed side by side in relatively large samples, they can sometimes be distinguished from each other, but in narrow lines it becomes essentially impossible.
Even when using colorblind assistant tools like firefoxes colorzilla addon or the free ware tool “whatcolor4” which displays color triplets used in screen images, it can be difficult for me to distinguish similar shades as color ditthering can create a situation where the user can find no pixel to sample that has exactly the same color triplet as the key used in the graph.
One help is to use physical indicators on the traces like different dash patterns or symbols like triangles and squares superimposed on the traces. Likewise explicit labels on the traces even if only a key number is helpful as by process of elimination you can determine which of two similar traces you need to follow.
The use of the visual key was very helpful on the primary trace to make it completely unambiguous.
Even on the larger image I have great difficulty determining with certainty, which graph trace corresponds to which data set for some pairs. The major problem is no two red green colorblind people see colors exactly the same as the condition covers a range of response differences. In my case I am almost totally blind to the color cyan, and have reduced sensitivity to red (it has much less visual impact to me than to someone with normal vision although I can see red it appears much darker to me than to someone with “normal” vision)
This makes color pairs like yellow and yellowgreen, pale blue and turquoise, blue and purple, dark brown and green, very dark red and black, royal blue and purple almost impossible for me to distinguish depending on color size sample size and color intensity (subdued colors, or pale tints being more difficult that stronger hue colors). One check you can make is to see that no two color traces resolve to the same gray tone if converted to monochrome image. Sometimes the easiest way to differentiate colors is to copy the image and modify it by shifting to different color depth displays, or use the color fill tool to change a line to a different color. Line weight is also a very good way to separate similar color shades in a multiple trace graph.
Thanks to anyone who takes that presentation issue into consideration when you prepare public data displays for large audiences!
Great analysis and very interesting conclusions about the value of some of the proxy data.
Larry
I’m just a “grunt” forester, but I have been that for 45 years. One thing that my education (I have a Master’s Degree in Forestry) and decades of observation have showed me is that within their normal range, tree rings are most affected by sufficient to excess mositure during the growing season and freedom to grow (ie. spacing – as someone said, “…all a tree needs to be happy is a place in the sun and a little piece of earth to call its own”). Trees are adapted to elevation, aspect, soils, climate and latitude among other more and less significant site and microsite effects. It seems to me, therefore, that comparing Bristlecone Pines from an extreme elevation in California to Spruce trees from the tundra line in Finland would present some formidable problems in statistical variability requiring controlling for multiple variables at once. I don’t know if that is somehow being done but I am very doubtful that one of those variables (climate) over hugely long periods can be effectively coaxed from any level and amount of data. I find it interesting to note that during the last ice age, Eastern White Pine grew on the Grand Banks off the coast of New England.
In describing the complexities of forest succession Botanist Henry Chandler Cowles observed in1901 that it was akin to,”a variable converging on a variable.” Surely, given the number of site related elements that affect tree ring width, the current effort is at least that complex.
sod (00:53:48) :
…linking the two of them removes an internal contradiction in sceptical writing, but produces a massive problem: a 500 year period warmer than modern times, would have lead to a massive effect on fauna and flora.
i haven t seen any discussion of this, beyond the incredibly weak “wine in england” meme.
That would occur if believing that warm environments could effect massively on fauna and flora.
The actuality is that warm environments don’t effect massively on fauna and flora as to cause extinctions and/or unusual stochastic or competitive radiation. Massive extinctions occur more often under cool environmental conditions or when clades are submitted to extreme stress by natural catastrophes; for example, intense volcanism, glaciations, epidemics, etc. A fluctuation of temperature between -3 and 3 °C (∆T = 6 °C) is quite normal during the Holocene and don’t cause extinctions or unusual radiations. That’s another biomyth spread on AGW propaganda.
Frank:
How did you get the un-altered NOAA data?
It was my understanding that all NOAA data was altered (time of day, station moves, etc.) and that raw data was not available.
timetochooseagain (07:03:14) :
Hey sod, where is the “massive effect on flora and fauna” from the Modern Warm Period? Your premise seems to be pretty wrong to me.
Nasif has already answered sod’s point, but just to clarify: his argument is that modern temperatures sustained over a 500-year period in the past must must have had an enormous impact on flora and fauna. His point is utterly unscientific.
Sod:
The only “massive effect on flora and fauna” is from extrapolation of computer models that have failed to predict climate variation during the past decade.
In order for those derivative studies to have any validity, the models have to be accurate. Beyond that they are nothing better than unscientific wild-ass guesses.
Any comments on the paper below, also in relation to this post?
http://www.eawag.ch/organisation/abteilungen/surf/publikationen/2008_wanner.pdf
This is worth repeating ( from the link Tree leaves control their own temperature, Penn study reveals http://www.eurekalert.org/pub_releases/2008-06/uop-fct061108.php . )
For decades, scientists studying climate change have measured the oxygen isotope ratio in tree-ring cellulose to determine the ambient temperature and relative humidity of past climates. The assumption in all of these studies was that tree leaf temperatures were equal to ambient temperatures.
It has clarified for me how the tree ring measurements are done. The time is taken from the ring cycles. One of the first things we learned in natural history in grade school was how the 11 year sun cycle was evident in the thickness of the rings. Even if other inputs affect the thickness of the rings, the yearly measurements are there to be counted. The temperature is measured by the the oxygen isotope ratio , which we recently learned is the temperature of the leaves, and the leaves tend to keep a constant temperature. So all the tree measurements are measuring the stability of the tree biology. No wander the temperatures are flat.
Frank, thanks for this great piece of work. Thanks to all for the links to the trees trying to maintain an ideal temperature, I filed the link with the article for future reference.
Dave Wendt (18:04:19) Your thought is my point. I wanted to throw it out because it gives perspective on the usefulness of tree proxies. Steve McIntyre has done extensive analysis on Mann, Briffa et al. I would encourage anyone interested in proxies to look at his work, it can be technical, but worthwhile.
John F. Hultquist (21:29:35) : Thank you.
And thank you Frank Lansner for this most informative post.
Regards, Allan
Sod:
The only “massive effect on flora and fauna” is from extrapolation of computer models that have failed to predict climate variation during the past decade.
this is false. the change can be seen by direct observation.
http://www.independent.co.uk/environment/changing-climate-sees-britain-offer-a-warm-welcome-to-new-varieties-of-wildlife-731456.html
http://www.independent.co.uk/environment/nature/britain-in-bloom-as-spring-is-sprung-earlier-than-ever-776174.html
if you prefer scholar article, a short search should bring enough hits for a lifetime of reading…
That’s some swell anecdotal evidence, sod.
If you’re trying to imply that CO2 is the cause, say it. If you’re trying to make the case that the planet’s drop in temps over the past few years caused a warm and wet past winter, say it. If you’re claiming the planet is currently warming, say it. If you’re assuming that the British isles are representative of the planet, say it. If you’re claiming that the climate usually doesn’t change, as most alarmists want us to believe, and that’s why this is unusual, say it.
If you missed the reams of comments posted here by people living there, who were telling us that this past winter was much colder than usual, and begging the planet to ‘send us some of that global warming’, then go back over the archives and tell us they were all wrong, and that those articles are accurate when they say “The unseasonably warm and wet winter so far in Britain has coaxed plants into early flowering.” Really? The past winter was unseasonally warm in GB?
Who should we believe? Posters commenting here about the extremely cold winter weather there, who have nothing to gain by fabricating their stories — or should we believe a very biased newspaper, which must sensationalize every story in order to stay in business? Or maybe we should believe someone who posts an article reporting on the winter of 2002, seven years ago. Who should we believe?
Next thing you’ll probably be telling us is that there was no MWP.
sod (00:53:48) :
“…linking the two of them removes an internal contradiction in sceptical writing, but produces a massive problem: a 500 year period warmer than modern times, would have lead to a massive effect on fauna and flora. ”
– Its sounds as though you really believe a little extra warmth would massively benefit all fauna and flora? Nice to have pointed out some good things about global warming, it doens happen so often.
Smokey, this is simple:
our planet has warmed significantly over the past 50 years. the evidence can be found in fauna and Flora changes basically everywhere.
if you don t believe those articles, feel free to read scientific articles on the same subject, or talk to gardeners. the story will not change.
if the planet was WARMER for 500 years during the MWP, we would have A LOT of evidence of similar changes.
i haven t seen that evidence.
Deadwood:
You asked about the RAW US temperatures.
Heres a graphic showing (fig 3) the raw US set.
http://www.klimadebat.dk/forum/attachments/ustemp.jpg
-in fig 4 i have compared with trend in US temperature records: A perfect match!
The background for adjusting is the official numbers:
http://www.coyoteblog.com/photos/uncategorized/2007/07/30/ushcn_corrections.gif
Thanks for the interest!!
sod,
Your first article was reporting on the winter of 2002. Why did you pick an article that stops at 2002?
Here’s why: click
Since 2002 the planet has been cooling.
And re the MWP: “i haven t seen that evidence.”
You are being deliberately blind to the really huge volume of evidence supporting a global MWP. You pick only the evidence you want to see. Cognitive dissonance claims another victim.
I just find it hard to understand why glaciers all over the world keep melting if the world is actually getting colder;
Glaciers will melt irrespective of whether the climate is warming or cooling. This is because all glaciers without exception are a process to transport ice from where it doesn’t melt to where it does melt.
If you meant glaciers retreating, i.e losing ice mass, then glaciers react to climate changes with a lag of decades to millenia.
Most temperate glaciers react with a lag of around 100 to 200 years. So we can say with confidence that the current climate is warmer than 150 years ago.
The real problem is the confusion between change and migration. There are many causes of migration and change of distribution of species. A sole explanation to migration, like attributing it to climate change = global warming, is confusing and not scientific. Migration has more than one explanation and it’s different for each species (Jablonsky et al. 1996).
For example, mosquitoes cannot fly more than 100-200 meters; however, we have found mosquitoes crossing the oceanic barrier. Obviously, those species of mosquitoes didn’t fly from Asia or Africa to America and they were not dragged by winds either; they were brought hidden in imported products. Many, many butterfly species expand their territories through eggs fixed on leaves of imported garden plants.
When we talk about radiation we’re referring to the production of new species; this is change. Other change could be the distribution of populations, communities, etc.; nonetheless, the latter change is due to multiple factors. When we talk about extinction we’re referring to a dying off of a clade; consequently, the examples on butterflies and frogs migrations not necessarily are due to climate changes. Migration not always leads to change.
As an illustration, we have a case of Columbina passerina L. (common ground dove) invading our very warm megalopolis. Columbina is a common inhabitant of mild and cold regions in Central and Southern Mexico, for example, Zacatecas, Jalisco, Guanajuato, etc. What is the cause of this territorial expansionism behavior from cold to warm regions? On this case, the climate obviously didn’t force them to migrate because Columbina population and climate on the regions from where they did come from have not been altered. We are working on finding a plausible cause; however, this expansionist migratory behavior is not exclusive of Columbina passerina and it fairly illustrates that the current behavior of territorial expansion of many species is happening on both ways, from warm to colder regions and vice versa.
Migrations from North to South or from warm to colder regions have also happened nowadays.
Population growth could be a plausible cause of migration.
Frank, you’ve really got me thinking about tree cover and the MWP doing so badly on the dendrochronology. It won’t let up and I suspect it may be significant. What if today’s CO2 rise, that is still continuing despite falling global temperatures, is in part because of ongoing loss of forests? What if it is the loss of forests in some places that has helped the increase of food production and the greening of the Sahel elsewhere? If you look at the seasonal CO2 fluctuations globally, the steady impacts of the tropical rainforests at those latitudes, and the seasonal impact of the Russian taiga at that latitude, are enormous.