Global Temperature Updates – 2012

By Paul Homewood

While Obama is imploring us to stop the global warming that is bringing us “the devastating impact of raging fires, and crippling drought, and more powerful storms”, it would seem to be a good idea to see exactly what global temperatures have been doing in the last year.

December Updates

First, let’s look at the December numbers, as there have been some significant changes.

December 2012 0.10 0.21 0.27 0.44
Change from last month -0.09 -0.07 -0.25 -0.24
12 month running average 0.19 0.16 0.44 0.56
Average 2002-11 0.26 0.19 0.47 0.59

[Remember all four sets are based on different base periods, so the absolute numbers are not directly comparable]

Points to note:-

  • Although HADCRUT and GISS show larger drops than the satellites, UAH and RSS both showed falls earlier in Oct/Nov, that were not matched by the others.
  • All three sets share a remarkable degree of agreement, in that the current 12-month average is running just below the 10 year average.
  • This month’s temperatures are remarkably low by historic standards. For instance, in the last ten years, there have only been three months when the HADCRUT figure has been lower.
  • ENSO conditions have been neutral for the last three months, and the temperature drops in the last couple of months appear to reflect the ending of a short lived El Nino conditions over the summer. More detail here.
  • The retrospective changes made by GISS, see here, are included in the above analysis. They tend to affect comparisons prior to 1998, rather than with recent years.
  • Quick analysis of HADCRUT data shows a larger drop of 0.41C in Northern Hemisphere temperatures, though Southern Hemisphere is also down by 0.09C.






Annual Summary

 Before we look at temperatures, let’s just see what the ENSO index has done this year.

The monthly figures for 2012 are :-

Month MEI
Dec 2011/Jan 2012 -1.046
Jan/Feb -0.702
Feb/March -0.410
March/April +0.059
April/May +0.706
May/June +0.903
June/July +1.139
July/Aug +0.579
Aug/Sep +0.271
Sep/Oct +0.103
Oct/Nov +0.166
Nov/Dec +0.037

The average for the year is +0.15, so it would be reasonable to classify it, overall, as ENSO neutral. Probably the last time neutral conditions applied for a sustained period was between April 2001 and March 2002. The current running averages for all four sets are close to or below the average seen in 2002.

Understanding this background is important when reviewing temperatures during the year.

The following graphs compare the annual temperatures over the last 10 years. None of them show any evidence of an increasing trend.





Perhaps the President might care to tell us what global warming he is talking about!


Temperature datasets are available  below.






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The concept of ‘trailing average’ puts a time shift on the smoothed data compared to the data the filter purports to be smoothing.
A smoothing filter outputs at the centre of the filter, not at either end.
The correct way to filter is to run the operator over the entire length of the data, and off the end of the data.

Tim Walker

Don’t confuse us with the facts. The situation is dire and getting more dire.

Peter Miller

And it looks like we are heading into a La Niña, so the 2013 is probably not going to be a good year for alarmists. Of course, their models could say different.
And the models is wot matters!


Note that GISS’s latest report shows the last decade at least being warmer by about .02C than what they were reporting last month. They warmed up the whole planet and only just realized it!

The same seasonality we have seen the last 2 years. Cooler anomalies in NH winter. Likely decreased clouds.

Krishna Gans

None of them show any evidence of an increasing trend.

Ask Rahmstorf, he will tell you s. t. about increaing trends
and fitted data

Werner Brozek

Similarly, Hadcrut3 dropped from 0.482 to 0.233 or a drop of 0.25. The average became 0.403. As a result, Hadcrut3 (as well as Hadcrut4) dropped from 9th to 10th warmest with the December numbers.

David L

Obama is simply denying the overwhelming scientific evidence.


Temperature anomiles resolved to 0.01° and MEI resolved to 0.001 (since 1950). Are the measurements that good?

Werner Brozek

The retrospective changes made by GISS, see here, are included in the above analysis. They tend to affect comparisons prior to 1998, rather than with recent years.
Check out 2007 with their latest data:
2007 93 66 67 71 63 55 57 58 60 57 54 46
Compared to WFT which still has the data prior to last week:
2007 0.89
2007.08 0.64
2007.17 0.65
2007.25 0.68
2007.33 0.62
2007.42 0.54
2007.5 0.56
2007.58 0.57
2007.67 0.53
2007.75 0.55
2007.83 0.49
2007.92 0.4

Goode 'nuff

Obama is only doing what he’s told. The ultra-wealth at the Environmental Defense Fund and Waltonville.
Light bulb went off… why don’t you advertise wuwt in the local Bentonville, Arkansas newspaper? That would get some attention. 😉 Maybe they’d publish some of the best of WUWT.
O Democrat
O Republican
√ educated


“[Remember all four sets are based on different base periods, so the absolute numbers are not directly comparable]”
Actually, as long as these four sets use different baseline periods, their annual cycles differ as well. For instance average RSS november temperature differs from average UAH temperature and the same for december, therefore even the difference between baseline november and december temperatures (in absolute values) is different and that affects the anomaly difference.
The only comparable data are annual average anomalies and anomaly differences between the same months in different years.

Just noticed WX Channel’s winter forecast-then look what they say about spring..!
“OK it’s cold now but just watch!!…”


It should be illegal to show an anomaly graph without noting the baseline temperature.

For those interested, earlier this month, I provided a sea surface temperature anomaly update, where the satellite-era sea surface temperature anomalies were presented on an annual basis:
They provide a slightly different perspective.


So when do we get to start calling the Alarmists, Deniers?? It seems they are the ones denying the reality of the actual temperature record over the last 15 years.


You are really not playing fair here when you use facts to determine the “truth”.


RSS and UAH are linked to reality
GISS and HadCrud, are linked to email.
Always find it funny that GISS and HadCrud started levelling off once real satellite data became available. And the all major adjustments made by Giss are to data before the satellite record.
Sorry Jim, but the period before satellite records is now immaterial.. SO LEAVE THEM ALONE.
Time to step away.. ITS OVER !!!
gees, maybe someone can even get rid of all your adjustments and take them back to the raw data…… now that would be interesting. !!

The traffic on the web in New England is unreal tonight, likely because this Global Warming is freezing everyone’s bleep off, and no one is leaving home. Below zero already in southern New Hampshire. So everyone is posting and the computer is very slow and seems to lose stuff when you try to post. So forgive me if this is a “double posting.”
Joe Bastardi predictly a nasty cold spell will “lock in” over the USA for a while, but that around the start of March the pattern ought “snap,” and the Eastern USA abruptly experience a balmy early spring.
Therefore my prediction is as follows: Dead silence on the part of the mainstream media until below-normal temperatures give way to above-normal temperatures, and then a deafening cacophony of hype.
Yawn. If only the weather was so predictable.

“It should be illegal to show an anomaly graph without noting the baseline temperature.”
I absolutely agree. I’ve thought that for a while. It’s bad enough that a poorly informed reader (like myself) see one and misunderstands what it reflects. It’s disastrous, however, in terms of properly informing the public if a news organization gets hold of one and mistakenly puts it out like it’s a temperature trend or raw data.

Jim McCulley

21 below at 9:40 here in Lake Placid. Thank god for global warming or it might be -22.

P. Solar

Thanks. Good, informative post.
You do label your running average as “trailing average” but It would be better if you just calculated the average centred on the data from six months either side. All your graphs show temps actually peaked in early 2010 but the averages all peak in late 2010. This is clearly inaccurate.
[Thanks – Paul]

James at 48

Quasi related. After a very brief tip of the hat to positive territory ENSO has plunged off a cliff. Now, as a result, here in CA:
This is really bad news as there will also be a return to the horrible cold stress this weekend.