I was preparing a few graphs for a chapter of my upcoming book (current working title An Illustrated Guide to Global Warming and Skepticism), and I thought readers here would find them interesting because they display global warming in a different light. The changes in temperature are minuscule when we look at the annual temperatures at all latitudes of the planet. I believe most of us are aware of that fact, and often times, because we’re looking at anomalies, we lose sight of the big picture. (Those warming signals would be even smaller if we were to consider the seasonal cycles and daily variations in temperatures…but those additional variations are beyond the scope of this post.)
In this post, we’re going to be looking at global temperature data and a reanalysis of global temperatures in absolute form, on a latitude-average (zonal-mean) basis, for two decade-long periods: 1979 to 1988 and 2003 to 2012. The purpose of the little exercise is simply to show how minute the rise in global temperatures has been when we compare the average temperatures for those two periods, while looking at the temperatures in 5-degree latitude bands from the South Pole to the North Pole. Then we’ll take a look at the climate model simulations of global land+ocean surface air temperatures for 2003 to 2012 and the final decade of the CMIP5 RCP8.5 (IPCC AR5) worst-case scenario, 2091 to 2100.
I’ve included the GHCN-CAMS land surface reanalysis because there are no land surface temperature datasets available in absolute form through the KNMI Climate Explorer. I’ve downloaded the data through to the current month and would have presented the latter period as 2004 to 2013, but the GHCN-CAMS reanalysis is missing temperature estimates at high latitudes in the Antarctic in 2013 and I did not want to bias the data there by a seasonal component.
First, a couple of preliminary graphs and discussions:
Figure 1 contains three graphs where the data and reanalysis are presented as anomalies…the form we’re used to seeing. Each dataset (and model output in the case of the GHCN-CAMS reanalysis) covers the period of January 1979 to December 2012, and also shown are the period-average temperature anomalies for periods of 1979 through 1988 and of 2003 through 2012. Looking at the top graph, we can see that global sea surfaces (HADISST) were about 0.17 deg C warmer in 2003 to 2012 than they were in 1979 to 1988. Lower troposphere temperatures (RSS), center graph, were about 0.30 deg C higher in 2003 to 2012 than they were in 1979 to 1988. And in the bottom graph, we can see that land surface air temperatures (GHCN-CAMS reanalysis) were about 0.74 deg C higher in 2003 to 2012 than they were in 1979 to 1988.
Figure 1
As a reference for the GHCN-CAMS reanalysis, GISS Land-Ocean Temperature Index (LOTI) data with the oceans masked shows land surface air temperatures were about 0.64 deg C higher in 2003 to 2012 than they were in 1979 to 1988. See the graph here. The fact that the GHCN-CAMS reanalysis is biased warm is good for this presentation. Just keep that in mind, please.
Another preliminary graph: In Figure 2, the average temperatures (in absolute form) are presented on a zonal-mean (latitude-average) basis. They show the average temperatures for the period of 1979 to 2012 in 5-degree latitude bands. That is, the vertical axis (y-axis) is temperature in deg C. The horizontal axis (x-axis) is latitude. The South Pole is to the left, the North Pole to the right, and the equator is at 0-degree latitude in the center.
Figure 2
Looking at the dark-red curve, the land surface air temperatures are by far the coldest in the Antarctic, averaging almost 40 deg C below zero near the South Pole for the period of 1979 to 2012. The tropics are, of course, much warmer, reaching just over 27 deg C at 12.5 degrees north latitude. And, as one would expect, average land surface air temperatures for the period of 1979 to 2012 cool again gradually until they reach their coldest temperatures for the northern hemisphere near the North Pole. The sea surface temperature data in light blue are, logically, also warmest in the tropics and they cool toward the freezing temperature of sea water in the polar oceans. Sea surface temperatures are, for the most part, warmer than land surface air temperatures. Then across the latitudes sampled by RSS, the lower troposphere temperatures are consistently cooler than both sea surface temperatures and land surface air temperatures.
Figures 1 and 2 probably give you an idea of what you’re going to see…better said, not going to see…when we compare the average temperatures for the periods of 1979 to 1988 and 2003 to 2012.
As a reminder, the GHCN-CAMS curve is the output of a computer model, meaning it’s not data. See Fan, Y., and H. van den Dool (2008), A global monthly land surface air temperature analysis for 1948-present. But they use data as inputs to the reanalysis model and the model infills regions without data. One of the datasets used as input is GHCN, which is used by the three primary global temperature data suppliers for land surfaces. I would be happy to present data, not a reanalysis, if and when a land surface air temperature dataset in absolute form is available through the KNMI Climate Explorer.
Figure 3 includes the comparisons of global temperatures on a latitude-average basis, with the average temperatures for the period of 1979 to 1988 shown in blue and the average temperatures for 2003 to 2012 shown in red. Sea surface temperatures are in the top graph, lower troposphere temperatures in the center, and land surface temperatures in the bottom graph.
Figure 3
Looking at the land surface air temperatures in the bottom graph, there is about a 65 deg C temperature difference between the average temperatures at the South Pole and the equator, and the two curves overlap (by the breadth of the default line chosen by EXCEL) in the Southern Hemisphere, showing how insignificant the changes in temperature have been there. It’s only when we reach the high latitudes of the Northern Hemisphere that there is a noticeable difference between the two curves. At 82.5N, the period average temperature for 1979 to 1988 is about -17.2 deg C, and for 2003 to 2012 it’s -16 deg C…a whopping 1.2 degree rise in temperature between those two decade-long periods.
WHAT ABOUT THE CLIMATE MODELS USED BY THE IPCC?
We’ve already presented that CMIP5 (IPCC AR5) climate models are not capable of simulating surface temperatures over any timeframe. For examples, see the posts:
- Model-Data Comparison with Trend Maps: CMIP5 (IPCC AR5) Models vs New GISS Land-Ocean Temperature Index
- Will their Failure to Properly Simulate Multidecadal Variations In Surface Temperatures Be the Downfall of the IPCC?
- Maybe the IPCC’s Modelers Should Try to Simulate Earth’s Oceans
- Models Fail: Land versus Sea Surface Warming Rates
But as a reference…
We often see maps of future global surface temperatures, where the maps have been color-coded to show everything in red. Example: Refer to the maps in Figure 4. They’re from the BBC article IPCC climate report: humans ‘dominant cause’ of warming. The Arctic temperatures are forecasted to warm more than 11 deg C by the end of the century for the worst-case RCP8.5 scenario on the right.
Figure 4
What they fail to tell us is that average annual temperatures (2091 to 2100) in the Arctic are still below freezing, as they are in Antarctica. See Figure 6, which illustrates the multi-model ensemble-member mean of the climate models stored in the CMIP5 (IPCC AR5) archive, for the worst-case (RCP8.5) scenario. Shown are the simulated annual temperatures on a latitudinal basis for the period of 2003 to 2012 and for 2091 to 2100.
Figure 5
Now consider that there are seasonal variations in temperature every year and daily variations in temperature every day.
CLOSING
As the title of the post read, this was simply a different perspective of global warming.
Many people hear that global temperatures have warmed a specific amount over a certain time period and realize they personally would never have been able to sense that change. The only reason they’re aware of it is the constant propaganda from talking heads. Maybe that’s why global warming falls so far down on people’s priorities on the UN’s recent poll. See the MyWorld2015.org poll The United Nations Global Survey for a Better World.
SOURCE
The data, the reanalysis and the climate model outputs are available through the KNMI Climate Explorer.
Bob,
David Hoffer did a simple analysis of the worst possible “catastrophe” as per the IPCC “science” and looked at actual temperatures of three cities and graphed the effect that it would have.
http://knowledgedrift.wordpress.com/2011/03/03/why-the-co2-greenhouse-gas-debate-doesnt-matter/#more-999
When you look at that analysis, fighting over the physics seems kind of irrelevant …
So the oceans won’t boil, who knew?
Bob, Why not “An illustrated Guide to Global Warming/Climate Change”.
I notice that the plots are in degrees C. If the absolute temperatures were used (degrees K) the change would look even far less significant.
The volume of “stuff” decreases to zero at the poles so the latitude scale should be non-linear. The divergence at the pole would seem even less important.
But what about the 1,000,000,000 Climate Refugees? Will they not need to move?
Another great post, Mr. Tisdale. The key word is ‘perspective’, as in “putting things in perspective.”
[Note: “pyromancer76” is “beckleybud” and “H Grouse”. He is the same sockpuppet. Banned multiple times. ~mod.]
Leonard Weinstein says:
May 4, 2014 at 6:54 am
I notice that the plots are in degrees C. If the absolute temperatures were used (degrees K) the change would look even far less significant.
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Leonard…..and if plotted on a thermometer….you can’t even find it
http://suyts.wordpress.com/2013/02/22/how-the-earths-temperature-looks-on-a-mercury-thermometer/
Very good Bob. This is a more realistic presentation of what is really happening.
Great post, now if someone has the skills to put predicted jules of energy (Hiroshma bombs would work) under each latitude numer, for that latitude, then we could see even further how far 6he observations are from the horriblle climate predictions.
Carbon dioxide is not well mixed in the mid-troposphere (where weather is located). It is also the case that its greenhouse affect is a regional to localized event. It can heat up the area it is in, while being less capable of doing that to any measurable degree where it is thinned out, and it certainly can’t heat up an area that is far away from the regional area the globby concentration is currently in.
This is the main reason it does not have an apparent or mechanized correlation with localized weather events, weather pattern variations, and oscillation in the short, medium, or long term time span (disregarding the seasonal correlation which is well observed but poorly modeled, and the correlation with large scale wind patterns moving it around, also well observed but poorly modeled, thanks to the AIRS project). While most CO2 globby and variable concentrations are in the Northern Hemisphere, the Southern Hemisphere has its own footprint complexity in terms of atmospheric CO2.
Because of this complexity, it will be a challenge for catastrophic climate scientists to demonstrate though observations and correlated modeling of localized extreme weather events with a CO2 presence of globby abundance with enough staying power to cause such an event. Chances are just as great that a glob of CO2 was NOT in the regional vicinity when the extreme event happened. Add to that the little bit of extra CO2 that is put there anthropogenically, and you have no case for human-induced increased deleterious or even beneficial anthropogenic CO2 affects. This is why I also suspect that global warming has not been caused by increasing CO2 and turn instead to natural oceanic/atmospheric teleconnections on decadal time scales as the null hypothesis yet to be disproven.
http://airs.jpl.nasa.gov/data/about_airs_co2_data/
Thanks, Bob. I think many will find this approach enlightening and eye opening. It’s SO obvious to those with the eyes to see. Your work is greatly appreciated.
What is the name of that island at 60 deg. south latitude, where they got their “land” surface air Temperatures ??
Oh I forgot; their computer just “modeled” what it would be if there was any land at 60 deg. south.
2 things that might be instructive – Instead of averages it would be nice to look at the total temperature variance to show the silliness of comparing a person having a 2 degree temperature to the earth changing 2 degrees (a human temperature only varies 3 degrees C over their life, the earth varies 70 degrees C
Also to show the anomalies on a scale that includes all recorded earth temperatures. The change will be almost impossible to discern at full scale
I did the same with 70N-90N and global temp many years ago. The global warming post 1970 s did not make sense. But then they changed the 70N-90N Data and nothing now makes sense.
I forgot to add Bob (as if you really needed more work to do) , what does it look like, if they added or “modeled” what the average “annual maximum” and average “annual minimum” global temperatures are ??
By “average” I mean over those years that are included in your plots, so that would likely not show the -94 deg. C for that cold plateau in Antarctica, or the + 57.8 deg. C record from north Africa.
And yes, it is very valuable to have a mental picture of what earth’s Goldilocks habitat REALLY looks like, so we can see how easy it is to live on this planet.. Thanks Bob.
g
Thanks Bob….looking forward to your new book. I notice the projected computer sea temp in the tropics exceeded 30 degrees. I have the understanding gathered from several sources that evaporation and resulting cloud cover at that temp worked to get her to keep the temp from rising above a sustainable +30C. Am I incorrect in this belief?
George e
Good point.
Perhaps “A sceptic’s illustrated guide to the catastrophic global warming scam.”?
I notice from your plots of the temperature changes on the two periods that you chose, the temperature increases are in the Northern Hemisphere mostly above 60 degrees. The climate model showed temperature increases for the entire Earth. The climate model outputs, if they were adjusted for no warming in the Southern Hemisphere and the same adjustment was applied for the total output, would be much closer to reality. Other than the fact that models have problems of drift and accumulated error, there is something basically wrong in the model.
Dear Bob,
It works even better if you plot the before and after curves on an absolute temperature scale. Across the entire Holocene, even.
rgb
When I started to read this article I thought at last someone is going to show temperature variations on the proper absolute scale, but alas they did not.
Where I live, in Rancho Mirage California, The seasonal variation is
295K in winter to 315K in summer or ~ 7% whereas the global warming variation over 100 years has apparently been less than 1 deg K or 0.3%. Thus seasonal variation is ~ 21 times the 100 year climate change variation.
Thanks Bob.
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Doug says:
May 4, 2014 at 6:54 am
“The volume of “stuff” decreases to zero at the poles so the latitude scale should be non-linear.”
“stuff” being a technical term used by those in the know
The distance along a Parallel of Latitude is a function of the angle of that latitude,
specifically the Cosine function.
Circumference at latitude L = circumference at Equator * cosine ( L )
Using 40,075 km. for the Equator,
Arctic Circle = 15,940 km
89° = 699 km
Thus, area and stuff will have to be scaled accordingly.
Hi Bob. Good luck with the book. You should also look at the extreme ranges on a per day basis, TMax and TMin since they use those to get TAvg for each day, then get TAvg for the year, and average those averages per station to give a regional average. In all those averagings we lose what is physically going on.
For example, using just summer Tmax for Canada stations we see that they are getting cooler since the 1930s. Winter TMin is warming more than TMax is cooling, so the TAvg for the years appears to be getting warmer. But the fact of the matter is the range of daily temps is narrowing since the 1930’s, and winters are getting less cold.
http://cdnsurfacetemps.wordpress.com/2010/06/23/july-temperature-trends/
The other aspect lost is the number of heatwave days. They have been dropping since the 1930’s. For any given day in July record temps fall in years before 1950, and were hotter than the few records set today.
http://cdnsurfacetemps.files.wordpress.com/2011/01/figure2a.jpg