I’m unable to setup a graph for these while I’m on the road, so a short table will have to do:
RSS (Remote Sensing Systems, Santa Rosa)
RSS data here (RSS Data Version 3.2)
RSS Jan09 .322
RSS Feb09 .230
UAH (University of Alabama, Huntsville)
Reference: UAH lower troposphere data
UAH Jan09 .304
UAH Feb09 .350
Oddly, a divergence has developed, and opposite in direction to boot. The only thing more puzzling today is Andy Revkin.
UPDATE: I spoke with Dr. Roy Spencer at the ICCC this morning (3/10) and asked him about the data divergence. Dr. Spencer had not yet seen that data, since he has been attending a conference. The data of course has been released by his associates and staff back at UAH. Here is what he had to say:
“I believe it has to do with the differences in how diurnal variation is tracked and adjusted for.” he said. I noted that Feburary was a month with large diurnal variations.
For that reason, UAH has been using data from the AQUA satellite MSU, and RSS to my knowledge does not, and makes an adjustment to account for it. I believe our data [UAH] is probably closer to the true anomaly temperature, and if I’m right, we’ll see the two datasets converge again when the diurnal variations are minimized.”
For layman readers that don’t know what diurnal variation is, it is the daily variation of temperature due to the variation of incoming solar radiation from rotation of the earth on its axis.
It looks like this:
Source: http://apollo.lsc.vsc.edu/classes/met130/notes/chapter3/daily_trend4.html
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
That is weird. The eye in the sky reports that Jan was colder compared to what the rabbit hutch on the ground reports. But then for Feb it reverses itself and says that the rabbit hutch reports colder temps than the eye in the sky does.
Now this is climate change.
Has anyone attempted to calculate error bars for global temperature measurements? Sounds like a job for Steve McIntyre. I laugh because earlier this afternoon I was having a hard time getting 4 thermocouples in the labs to agree with each other within 0.25 degC.
I don’t know whether to cower in fear or sigh with relief…
Perhaps this is good evidence of why we need several different mechanisms for measuring temperature change to provide a more objective basis to the data.
(Instead of just relying on surface temps…)
Is ice measured very differently than temperature? Are they different satellites?
It is common that there is a difference between UAH and RSS.
Since about 10-12 year ago a 12 month cyclic error has appeared.
Se diagram that shows the difference between RSS and UAH.
Normally at this time of year the difference between RSS and UAH should be small. I guess it will get back on track next month.
The error reaches its maximum in the summer.
is the 12 month running mean error between RSS and UAH.
Making a second try to make links work….
I wish there was a preview function available.
It is now obvious, I have no clue how to make links work in this blog. :/
I do it the textstyle way.
http://www.flickr.com/photos/22768673@N05/2559561428/
http://www.flickr.com/photos/22768673@N05/2558758077/
Temperature trends from 2002 til today:
http://www.klimadebat.dk/forum/attachments/feb.gif
This is weird. I read everywhere that the globe is in a downwards temperature mood. El nina, no solar activity, cold winters in parts of the NH,……and yet and yet….Global temperature stays above average ?
Would it not be logical that in periods like these where all know natural influence point to cooling that the global temperature would be significant below average ?
UAH is higher than I expected, but still coolest Feb since 2001…
Climate4you keeps an excellent graphical record of temperatures
http://www.climate4you.com/
Difference between UAH and RSS
When you compare the details, you realize that the SH and tropic data show the same trend in both data sets, but NH differs strongly.
tot NH SH trpc
UAH 2009 Jan 0.304 0.443 0.165 -0.036
UAH 2009 Feb 0.350 0.685 0.016 0.051
RSS 2009 Jan 0.322 0.449 0.190 0.067
RSS 2009 Feb 0.230 0.391 0.062 0.130
The UAH increase seems to be consistent with the AMSUA daily temperatures.
The more detailed data:
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt
and
ftp://ftp.ssmi.com/msu/monthly_time_series/rss_monthly_msu_amsu_channel_tlt_anomalies_land_and_ocean_v03_2.txt
are not yet out.
A tenth of a degree difference?
I don’t really think it’s significant. This is hardly an exact science after all.
According to JunkScience, UAH is in at +0.30,
and not +0.35.
http://www.junkscience.com/MSU_Temps/Warming_Look.html#SIDC
That would be in the ballpark.
Ooops.
Ignore my last comment. I was looking at UAH January temps.
This two measurements diverge by a total of 0.138. That is such a large amount that there has to be some gross error somewhere. Or has this happened before?
My first thought was RSS doesn’t include the poles but UAH does. Then the “Sudden Stratospheric Warming” phenomenon that Bill Illis reported on last month in a comment came to mind. But with respect to the inclusion of the poles, the NCDC’s version of global land and sea surface temp based on ERSST.v3b shows a decline this month too and it includes the poles.
ftp://eclipse.ncdc.noaa.gov/pub/ersstv3b/pdo/aravg.mon.land_ocean.90S.90N.asc
So that would seem to confuse matters more. Hmm!
And for those into information overload, the OI.v2 SST data shows a decline in global SST anomalies:
http://bobtisdale.blogspot.com/2009/03/february-2009-sst-anomaly-update.html
But there were a few positive SST datasets in the OI.v2 SST data. The North Pacific, the Indian Ocean, the Arctic, and the Southern Oceans were positive, leading me back to the probability that the divergence between the RSS and UAH data may be how they handled the poles.
AMSU seems to indicate UAH rather than RSS to be correct. Unless there is a systematic error. AMSU has indeed shown some significant fluctuation this year. The latest example – the recent March rise of .33C in six days…
Willem de Rode: This is the sort of thing that puzzled me, until I formed the view that natural variation (particularly the Pacific Decadal Oscillation) was masking a genuine underlying warming trend from AGW.
I explain why I became a climate skeptic here.
And why I recanted here.
And where I assess whether we should try to do something here.
What is the difference between the UAH data linked in the post and this link:
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt
John M Reynolds
Do RSS and UAH cover the same area? Looking at the raw data for RSS (ftp://ftp.ssmi.com/msu/monthly_time_series/rss_monthly_msu_amsu_channel_tlt_anomalies_land_and_ocean_v03_2.txt) it looks as if the RSS data covers 82.5N to 70S, so it’s overweighted for NH. My recollection is that UAH is more uniform, so the current difference and cyclical difference (see Jerker post ~5) would make sense if the Antarctic is typically warm in the late southern summer. It looks like they do some adjustment, as RSS global temp is not an exact average of NH and SH temps, but it’s pretty close. I think I trust the UAH with better coverage.
Willem de Rode (23:28:58) :
There is no “average” world temperature. The charts we refer to when we talk about anomalies refers to an average of temperatures taken at an arbitrary interval of time. It really doesn’t matter what that interval is, as long as everyone uses the same baseline.
With satellite data we are limited to the years when satellites were first put into orbit. That data is only about 30 years. Collectively, everyone with an interest in the subject could use any interval as the “average”.
One of the biggest misconceptions out there is the planet is warmer, or cooler, than average. There is no average. There is no optimum.
For a really good discussion of this topic, see http://www.climate4you.com/ClimateReflections.htm#Reflections%20on%20recent%20global%20temperature%20changes
And see a good discussion of the relationship between CO2 concentrations and world temperatures
http://www.climate4you.com/ClimateReflections.htm#20080927:%20Reflections%20on%20the%20correlation%20between%20global%20temperature%20and%20atmospheric%20CO2
The author of climate4you has a very calm approach to this whole topic and is very thorough in his documentation. It is my second favorite website on this topic.
To Jack Simmons,
I agree with your remark. Of course the so called average global temperature is only an average of temperatures measured via the same methode over a limited period of time.
But even then, if we consider the average global temperature over the period 1980 to 1995 as reference. Still then my remark is standing solidly !
Now, all known natural variance parameters are pointing to lower temperature conditions. As I can read on this and similar blogs, this is an unique coïncidence that maybe only is seen before during the Little Ice Age.
But yet, uless all conditions, the average global temperature of the last months is still higher than the average global temperature of the reference period (in which some natural conditions lead to warming !).
Regardless of defintitions of global average temperatures, this seems very odd to me.
With all information I can read about the natural temperature-influencing parameters I expect logically that the global temperature would be lower than in these periods in which these parameters would facilitate warming. Discussions about definitions of references will never solve this rather simple logical problem.
OT:
What’s up with that? Strange NASA sun images. The sunspots are back, and they are back with a vengeance!
http://umbra.nascom.nasa.gov/images/latest_solisHe_thumbnail.gif
http://umbra.nascom.nasa.gov/images/latest_nsoHe.gif
From here:
http://umbra.nascom.nasa.gov/images/
Since 2002 temperatures near the earth surface have not changed much, they are flat. However if I look at the temperature at a height of 36km., using the AMSU-A data, I see that from 2002 to 2008 there has been a fall of almost 1 degree C. From 2008 to 2009 there is a further 0.5 degree C fall.
The upper atmosphere is cooling quickly. It seems to me that the surface is being kept at a constant temperature by heat stored in the oceans while the upper atmosphere is cooling because of less energy from the sun.
I therefore predict more cooling at the surface.