Up slightly from .489 last month to .511 a change of .022 degrees C
August 2010 UAH Global Temperature Update: +0.51 deg. C
By Dr. Roy Spencer
While the global-average lower tropospheric temperature remained high, +0.51 deg. C in August, 2010, monitoring of the daily Aqua Ch.5 data at the Discover web site suggests that the cooling of global average sea surface temperatures that started several months ago is now causing the troposphere to cool as well. I will probably provide an update of that plot tomorrow.
Plot and recent data below:
YR MON GLOBE NH SH TROPICS
2009 1 0.251 0.472 0.030 -0.068
2009 2 0.247 0.565 -0.071 -0.045
2009 3 0.191 0.324 0.058 -0.159
2009 4 0.162 0.315 0.008 0.012
2009 5 0.139 0.161 0.118 -0.059
2009 6 0.041 -0.021 0.103 0.105
2009 7 0.429 0.190 0.668 0.506
2009 8 0.242 0.236 0.248 0.406
2009 9 0.505 0.597 0.413 0.594
2009 10 0.362 0.332 0.393 0.383
2009 11 0.498 0.453 0.543 0.479
2009 12 0.284 0.358 0.211 0.506
2010 1 0.648 0.860 0.436 0.681
2010 2 0.603 0.720 0.486 0.791
2010 3 0.653 0.850 0.455 0.726
2010 4 0.501 0.799 0.203 0.633
2010 5 0.534 0.775 0.292 0.708
2010 6 0.436 0.550 0.323 0.476
2010 7 0.489 0.635 0.342 0.420
2010 8 0.511 0.672 0.349 0.362
As of Julian Day 243 (end of August), the race for warmest year in the 32-year satellite period of record is still too close to call with 1998 continuing its lead by only 0.06 C:
YEAR GL
1998 +0.61
2010 +0.55
As a reminder, six months ago we changed to Version 5.3 of our dataset, which 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 as in Version 5.2. ALSO…we have added the NOAA-18 AMSU to the data processing in v5.3, which provides data since June of 2005. The local observation time of NOAA-18 (now close to 2 p.m., ascending node) is similar to that of NASA’s Aqua satellite (about 1:30 p.m.). The temperature anomalies listed above have changed somewhat as a result of adding NOAA-18.
[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.]
The 20-year period was selected, I presume, because, there was not 30 years of data when anomalies were first being calculated against a baseline.
As has been pointed out above, it makes no difference what the baseline is. Keeping it the same makes it a much simpler matter to compare data. If you change the baseline, then every bit of data has to be changed, and the data is somewhat prominent in the blogosphere. It’s the same reason NSIDC stick with their baseline – it makes year-to-year comparisons awkward, especially when having to explain to interested public unfamiliar with base line and anomalies.
Can’t think of any good reason to change the baseline, up down or whatever. Just keeps things straightforward. Reminds me of the argument about imperial and metric. The length is the same, only the standard by which it is measured changes. I guess it would be like the MSM suddenly decding to use using metric scale when reporting in the US – they’d have to spend time explaining what it means in imperial terms anyway.
Depends what you’re looking at. For the entirety of the satellite record, UAH is the outlier and GISS is closer to the other 2 (RSS and HadCRUt).
http://www.woodfortrees.org/plot/gistemp/from:1979/trend/offset:-0.209/plot/rss/from:1979/trend/offset:0.024/plot/hadcrut3vgl/from:1979/trend/offset:-0.128/plot/uah/from:1979/trend
Not that the deviation is terribly significant. The biggest difference between the trends is 0.03C/decade. Storm in a tea-cup material.