February 2010 UAH Global Temperature Update: Version 5.3 Unveiled
by Roy W. Spencer, Ph. D.
The global-average lower tropospheric temperature remained high, at +0.61 deg. C for February, 2010. This is about the same as January, which in our new Version 5.3 of the UAH dataset was +0.63 deg. C. February was second warmest in the 32-year record, behind Feb 1998 which was itself the second warmest of all months. The El Nino is still the dominant temperature signal; many people living in Northern Hemisphere temperate zones were still experiencing colder than average weather.
YR MON GLOBE NH SH TROPICS
2009 1 0.213 0.418 0.009 -0.119
2009 2 0.220 0.557 -0.117 -0.091
2009 3 0.174 0.335 0.013 -0.198
2009 4 0.135 0.290 -0.020 -0.013
2009 5 0.102 0.109 0.094 -0.112
2009 6 0.022 -0.039 0.084 0.074
2009 7 0.414 0.188 0.640 0.479
2009 8 0.245 0.243 0.247 0.426
2009 9 0.502 0.571 0.433 0.596
2009 10 0.353 0.295 0.410 0.374
2009 11 0.504 0.443 0.565 0.482
2009 12 0.262 0.331 0.190 0.482
2010 1 0.630 0.809 0.451 0.677
2010 2 0.613 0.720 0.506 0.789
The new dataset version does not change the long-term trend in the dataset, nor does it yield revised record months; it does, however, reduce some of the month-to-month variability, which has been slowly increasing over time.
Version 5.3 accounts for the mismatch between the average seasonal cycle produced by the older MSU and the newer AMSU instruments. This affects the value of the individual monthly departures, but does not affect the year to year variations, and thus the overall trend remains the same.
Here is a comparison of v5.2 and v5.3 for global anomalies in lower tropospheric temperature.
YR MON v5.2 v5.3
2009 1 0.304 0.213
2009 2 0.347 0.220
2009 3 0.206 0.174
2009 4 0.090 0.135
2009 5 0.045 0.102
2009 6 0.003 0.022
2009 7 0.411 0.414
2009 8 0.229 0.245
2009 9 0.422 0.502
2009 10 0.286 0.353
2009 11 0.497 0.504
2009 12 0.288 0.262
2010 1 0.721 0.630
2010 2 0.740 0.613
trends since 11/78: +0.132 +0.132 deg. C per decade
The following discussion is provided by John Christy:
As discussed in our running technical comments last July, we have been looking at making an adjustment to the way the average seasonal cycle is removed from the newer AMSU instruments (since 1998) versus the older MSU instruments. At that time, others (e.g. Anthony Watts) brought to our attention the fact that UAH data tended to have some systematic peculiarities with specific months, e.g. February tended to be relatively warmer while September was relatively cooler in these comparisons with other datasets. In v5.2 of our dataset we relied considerably on the older MSUs to construct the average seasonal cycle used to calculated the monthly departures for the AMSU instruments. This created the peculiarities noted above. In v5.3 we have now limited this influence.
The adjustments are very minor in terms of climate as they impact the relative departures within the year, not the year-to-year variations. Since the errors are largest in February (almost 0.13 C), we believe that February is the appropriate month to introduce v5.3 where readers will see the differences most clearly. Note that there is no change in the long term trend as both v5.2 and v5.3 show +0.132 C/decade. All that happens is a redistribution of a fraction of the anomalies among the months. Indeed, with v5.3 as with v5.2, Jan 2010 is still the warmest January and February 2010 is the second warmest Feb behind Feb 1998 in the 32-year record.
For a more detailed discussion of this issue written last July, email John Christy at christy@nsstc.uah.edu for the document.
[NOTE: These satellite measurements are not calibrated to surface thermometer data in any way, but instead use on-board redundant precision platinum resistance thermometers (PRTs) carried on the satellite radiometers. The PRT’s are individually calibrated in a laboratory before being installed in the instruments.]
“”” David (16:01:37) :
Thanks Dr Christy: I apologise if this is a stupid question, but what effect if any does the high albedo from the exceptional northern hemisphere snow cover in recent months have on your measurements? “””
Only stupid questions are the ones not asked.
Seems like a higher albedo, would make the surface colder; but maybe the upper atmosphere warmer due to double pass of incoming solar; but that just a WAG; what do I know about such things.
Is rather interesting though to contemplate just what this EN is doing; was the 1998 El Nino at the same time of the year, or some other season ?
It’s good to see you defending satellite observation Roy. However; mikelorrey (16:37:52) has a valid query.
To ensure stability in an electronic circuit that may be required to operate accurately beyond its expected environment an identical circuit is often incorporated within the device. The purpose of the identical circuit is to give an identical ‘feedback’ of environmental aberrations (noise), which when added to the sensor output as an inverse signal, permits the signal to emerge without the noise from the adverse environment.
Can you show this?
Best regards, suricat.
Where on earth are the very hot regions that are causing the global mean to be so high?
They must be very extensive and powerful as many sections of the northern hemisphere have been unusually cold.
I understand that New Zealand has had a cool summer. Here in Australia, the summer started off being very hot, particularly in Adelaide.
In Sydney, we had a hotish early period, but in general summer has been quite mild. It’s been so wet this year (similar to the 1950’s I recall), that it has been very, very humid. That makes it feel hot, but the thermometer says, no, quite normal to coolish for summertime.
So where oh where are the very hot places?
Are the satelite sensors able to penetrate clouds and the humid air and accurately intrepret the resulting signal.
I understand that satelite temperature measurements are very accurate. But are they measuring temperature on earth, or something rather different?
The reason why January/February are the warmest months will probably be because the earth’s orbit has its closest approach to the sun (perihelion) in early January.
Can’t seem to find a correction applied due to the vast decrease in the atmosphere’s volume over the last few years. If this particular calibration is implied by another more direct correction or parameter, could you let other here know that?
Since persons here now speak with other people from all over this globe, it is becoming very clear that something may be amiss. Every place seems mild or downright cold, where is the hot spot or mis-calibration occurring? AMSUs infer direct temperatures, not merely anomalies, and then the anomalies are derived from the direct temperatures. Any help Roy, even if you can only give possibles?
Ref:
AMSU-A Level 1B Calibrated, Geolocated Radiances
http://disc.sci.gsfc.nasa.gov/AIRS/data-holdings/by-data-product/amsuL1B_Rad.shtml
Agree with you Mooloo. Where is it actually warmer? Numbers are all very well but try sticking your head out of the door instead of in the sand. NZ has had a very cold winter and a cooler summer. We have lit the fire
3 times in January. In fact we have had fires over 10 months of last year.
Traditionally we would start having fires in late April and discontinue them
in October(in general,we don’t have central heating in our houses downunder).
The growing season has been shorter also here in the South.
From the WINC file in Chicago: “Mild” winter with above average snow.
Lowest temp. -2F
Last year was -18F (Will the car start? cold).
Almost no ice on the “great lakes” this year, lots of ice last year.
Last 3 years have worn out 3 snow shovels, they used to last 5 years (during the “warming”).
I still remember the “next ice age scare”, it was great, I was a kid.
Source code?
The earth is very warm indeed compared to the long term average, I wonder what’s causing it?
YR MON GLOBE NH SH TROPICS
2010 1 0.630 0.809 0.451 0.677
2010 2 0.613 0.720 0.506 0.789
YR MON GLOBE NH SH TROPICS
2010 1 0.630 0.809 0.451 0.677
2010 2 0.613 0.720 0.506 0.789
Could someone explain this to me please? It appears to show the NH as experiencing the greatest warmth.
Now I’m really confused!
Also, still waiting for response to my questions on if it’s normal for all Aqua AMSU data to fail QA and if it’s normal for channel 4 to have zero readings for a month.
George E. Smith (17:59:04) :
“Is rather interesting though to contemplate just what this EN is doing; was the 1998 El Nino at the same time of the year, or some other season ?”
The hottest months were Feb
http://www.cpc.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml
The hottest months were Feb and April
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt
Also wondering if it’s normal for two different months that have nearly identical raw readings (i.e. Jan, 2009 and Jan, 2010) to produce an anomaly where one is more than twice the size of the other.
I think you will find that UAH and RSS have higher temps than giss etc because they are meassuring warmer oceans that of course make up 71% of the planet’s surface.
The land areas probably were cooler but with the el nino influence the temp over the oceans easily overcame the much smaller land area.
Steve Goddard,
Interesting question, I was thinking the hot spot was SST in the Pacific due to El Nino, but haven’t seen an official answer on it. Would be interesting to see if this is only SST or affecting land as well.
Dr. Spencer/Anthony/Anyone,
I understand that from 2002-current the sat (AQUOS?) uses internal calibration (very clear, and nice move with the footer BTW), was that also the case for the RSS sats (1979-2001)?
Can Dr Spencer be specific and tell us where, exactly, in the Northen Hemisphere we are experiencing these enormously high temperature anomalies?
In Europe we are experiencing 20 to 30 year low temperatures. A good portion of North America has been colder than average. The Arctic is showing strong ice growth indicating low temperatures. These ‘hotspots’, where ever they are, have not just got to be hot in relation to their own geographical location after all but to be so hot that they can overcome the very low temperatures that a lot of us have actually experienced and then go on to raise the overall average temperature anomalies to near record levels.
Now that has to be really hot in these places and also very extensive!
So where are these places, exactly, so that we can check and talk to posters here who live there, or close to there, to check their actual experiences.
I really feel this is important because whilst we have, what is becoming, a rather vague ‘Northern Hemisphere anomaly’ which seems to be the opposite of what real people in real places are actually experiencing then gaining credence for the measurement process will be difficult.
Alan
Hide the incline?… massaging data..seems convenient that just as Feb reaches a record high, 0.12 deg C is lopped off.
Seems there are two standards, if GISS changes data it is a conspiracy, but UAH changes data and not a peep
Guys! I think we would all do well to remember that we live on a ‘water world’ that affects land surface climate! Thus, there are some, perhaps in some instances ‘short’, differences between our perceptions of the way that energies flow between land surface and sea surface.
Best regards, suricat.
[/quote 4 billion (19:04:27) :]
Hide the incline?… massaging data..seems convenient that just as Feb reaches a record high, 0.12 deg C is lopped off.
Seems there are two standards, if GISS changes data it is a conspiracy, but UAH changes data and not a peep
[/quote]
.
Perhaps you missed my 3 posts giving reasons I find these results questionable?
.
If you think that skeptics are giving UAH a free pass, they are not. I’ve got a 2 month series of posts on the issue as well as an open-source project underway to attempt to verify UAH results. See here: http://magicjava.blogspot.com/2010/03/amsu-limb-adjustment.html
and here: http://magicjava.blogspot.com/2010/02/amsr-e-and-amsu-hdf-eos-c-readers-are.html
Both of those posts are to the end of a series of posts on the topic, with links to previous series.
I’ve also e-mailed requests for source code to Dr. Spencer and to NASA, neither of which were granted. I’ve also e-mailed questions I have regarding the data to Dr. Spencer, Dr. Christy, and NASA. None of my questions have been answered.
@Mike Borgelt (16:31:35) :
There have been a series of these satellites with those PRTs on them. The “experimental data” you request is that we’re not seeing step changes when one satellite with a new PRT replaces an old satellite with an older PRT that’s been exposed to the factors you describe.
P.S. Just to be fair, Dr. Christy did answer a question about the day/night flag in the AMSU data. But that question was a hypothetical and had nothing to do with whether or not the data used by UAH is valid.
That’s a whole lot of adjusting that Dr. Christy is talking about.
Everybody seems curious about how it can be so cold where people are but apparently warm globally. Well the highly negative AO conditions precipitated such cold weather are manifest where people live, yes, but the effect of the AO is dual. When you get cool air in the US etc. the air in the Arctic-where few people live-is anomalously warm.
For example:
http://icecap.us/images/uploads/dec1-feb22.JPG
So I’d bet when we see the UAH map (John will probably release it at some point) it will show that the anomalies are more positive in those areas where people aren’t.
4 billion (19:04:27) : Posh, conspiracy theorists like you make all kinds of peep. John has been working on this fix since June.
NickB. (18:50:18) : The MSU’s indeed calibrate the same way, I believe.