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.]
JChristy (05:35:19) :
Am I correct to understand that you measure what the temperature of the oxygen is, without making any sort of judgment as to what heated the oxygen?
phlogiston (05:23:49) :
There is a reason I only bet a nickel on future forecasts. I expect to be surprised, and often to be wrong, because in all honesty I think we have a great deal to learn.
We cannot really use the 1998 El Nino as a predictive tool, because the PDO was in its warm phase in 1998. Now it seems to be starting into its cool phase, and this means we will be looking at an entirely different series of actions and reactions.
If you go look at page 24 of the NOAA site at:
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
you can get a feel for how different the cycles of La Nina and El Nino were during the cool phase of the PDO. For Example, during the 75 months from January 1950 to March 1957, there was only a single five-month El Nino.
One problem is that the record starts in 1950. There was a pretty good La Nina in 1949, and the El Nino before that would be interesting, as it likely has a lot to teach about the border between warm and cool phases of the PDO.
To learn about pre-1950 El Niño and La Niña episodes it helps to know Spanish, for the South Americans were the ones studying the stuff off their shores before 1950. North Americans didn’t really focus on how far away events effect North American weather until Navy meteorologists returned from the Pacific after World War Two, and it took those young fellows a while to get their bosses to listen.
It would be nice to be able to state, in a step by step fashion, how actions and reactions cause a warm PDO to give way to a cool one, and then how a cool PDO gives way to a warm one, but I don’t think science is able, yet. We are still at the point of observing all the steps, and we haven’t even seen all the steps of the roughly sixty year cycle, using our wonderful modern satellites.
I think Bob Tisdale offers a invaluable service simply by making the data easier to grasp, with graphs and animations. He demonstrates what seems to be a hand-off of energy from the El Nino to the more northern waters, by pointing out a “step change” in graphs. However this is only a very astute observation, and likely represents one step out of many. There also seems to be a delayed reaction in the Atlantic, as the AMO changes to its warm phase in a manner that lags the PDO.
Dr. Bill Gray suggests deep sea currents might have an important role and even be a trigger, but I have been very frustrated in my attempts to find any decent measure of thermohaline circulation, or of waves traveling through the thermocline. All I see in current data are incoherent blobs that seem to have no rhyme or reason, and seemingly suggest thermohaline circulation doesn’t even exist, (though we know it does.) Most people simply ignore it, and focus on sea-surface temperatures, pressure patterns, and trade winds.
You will notice air temperatures hardly matters. Air temperatures are more of a by-product of weather patterns, trade winds and sea-surface temperatures than a cause.
It is for this reason I shake my head over the fact Hansen and Jones have squandered billions of dollars monkeying around with air temperatures. We have all these people adjusting temperatures from 1889, because some farmer switched from raising corn to raising sheep in the field beside the thermometer. Then Anthony and friends come along and show the way they monkeyed with the temperatures is highly suspect. I am very glad Anthony and friends have performed this service, for it seems to show the adjustments were unscientific and based upon preconceptions, however, if we truly have all this time and money to spend, I think it would be better spent studying what causes the PDO to shift, and what controls El Niño and La Niña episodes.
JChristy (05:35:19) :
(…)
Kadaka: Variations in land emissivity have been studied as possible noise to the microwave temperature signal (e.g. drought to moist over time). The effect was tiny, < 0.01 K for global average. Mountains don't move around, so their consistent impact is removed in the anomaly calculation.
(…)
Unfortunately I was not talking about land emissivity, like with wet to dry. I was talking about how things above an observer on the ground can be heated, that heat can be seen by a satellite, yet most of that heat does not reach the observer. Forests are primarily heating the air, the satellites measure those air temperatures, but the ground does not see all that heat. So the satellites end up measuring higher temperatures than what a ground-based observer would. In a similar way, higher geological features like hills and mountains will be heating a lot of air, that the satellites will notice, that will not benefit those living in the valleys.
So the UAH numbers can be showing record heat, yet down here on the ground it’s still pretty cold. The satellites are measuring heat that we are not sensing.
R. Gates:
“The extended solar minimum is barely over and already tropospheric temps are near record levels. With or without El Nino lingering, 2010 will beat 1998 as the warmest year on temperature record, (yes, it was warmer a long time ago, but humans weren’t the issue as the trigger a long time ago).
How will AGW skeptics paint the global warming going on in 2010? To what will they ascribe it? It will interesting to see how the worm will turn on the warm to come…”
Well, first of all, we MIGHT be at the end of the extended solar minimum, but this entire cycle is projected to be well below previous cycles, so that should nto be too much of a worry.
Second of all, if it was warmer “a long time ago” and humans were not a trigger for that warming, then it is pretty darn likely that humans are not a trigger for current warming either by normal logic. Your speculation that 2010 will beat 1998 as the warmest year on record is just that, speculation.
Come back in 9 more months and see if that worked out for you or not.
However, the whole statement you made about it being warmer a long time ago without humans being the trigger for the warming means that logically you have to admit the possibility that humans are not the trigger for the current warming either, since it has happened in the past without human influence, so you kinda destroyed your own intent to cause us any worry about human activity by including that disclaimer in there.
Kadaka,
Just from what I feel would be a reasonable perspective, if the temperature at the surface is pretty cold, the warm air has to go somewhere… after all, there has to be some sort of energy-balance. There are several possibilities. If the US gets extremely cold, other places (Western Canada) get abnormally warm.
Another possibility, cold air near the surface displaces warmer air which rises into the troposphere, making the troposphere abnormally warm while the surface freezes.
Not sure if possibility #2 has any real validity or not, but at least to me it seems plausible.
I accept the that the uah figures are right but The Winter we have had in the the uk has been the coldest for over thirty years, I would not have believed that possible last november.The arctic temperature remains below average and the ice area and extent is the highest in the last four years.the baltic sea is full of ice maybe next year we will see the thames freeze over.The river where I live did freeze over for the the first time since 1963 it did not last long enough for anyone to skate on this as they did in 1963 but maybe next year.I think that if we continue to see arctic ice recovery this year then we will likely have another cold winter next year in the northern hemisphere despite the elnino
In Vermont, winter came weeks late (ski area openings). Spring is happening, weeks early. In between-high temps slightly cooler than normal, low temps well above normal. March, often in like a lion, out like a lamb-looks like an extended lambing season this year.
Spring is late in coastal northwest Wales. There were no local daffodils in bloom ready for St. David’s Day (March 1st). Night time ground frosts continue.
As they say ‘Don’t try this at home!’. I’ve taken the liberty of putting the 5.3 dataset into a Excel spreadsheet, with a little pivot table and graph. It’s in Google Docs.
http://docs.google.com/leaf?id=0B9nJpvPnppwlMmE5NTg3YWMtZDEwNy00ZDE4LWIzODItYjkzNjk4NWFmMDUx&hl=en
E & O.E. This comes with no warranty, responsibility etc. Enjoy!
PeterB. said:
“Second of all, if it was warmer “a long time ago” and humans were not a trigger for that warming, then it is pretty darn likely that humans are not a trigger for current warming either by normal logic.”
Peter, this is actually not logical at all. What you’re saying is that the ONLY way global warming can occur is through natural cycles, variations, etc. which in logic means B only can follow A, and never anything else, when in fact, there is no proof of such, and that is exactly what AGW researchers are looking at, namely, can B sometime follow C, and in this case C=human activity (namely a rapid increase in CO2).
R. Gates:
“The extended solar minimum is barely over and already tropospheric temps are near record levels. With or without El Nino lingering, 2010 will beat 1998 as the warmest year on temperature record, (yes, it was warmer a long time ago, but humans weren’t the issue as the trigger a long time ago).
How will AGW skeptics paint the global warming going on in 2010? To what will they ascribe it? It will interesting to see how the worm will turn on the warm to come…”
We’ll keep this on record – something to laugh about this time next year.
Its also amusing how prior to 2006 AGW proponents rejected and ignored the possibility of solar changes affecting climate – but now it is grasped as a fig leaf to account for recent cooler temperatures.
OT – but today there are heavy snow and blizzards on the Mediterranean coast:
http://news.bbc.co.uk/2/hi/europe/8557570.stm
Is the Med coast in the troposphere?
Last July there was a thread on here parodying GISS for having higher anomalies in May and June than UAH: “GISS for June – way out there”.
I guess we now know that it was UAH that was at fault, as was correctly suggested by poster Paul K, for which he was attacked by many in the 250-odd posts.
Paul K (09:07:50) :
Next point, I applaud you for headlining the difference between UAH and GISS for June, as you did in May. Every year you trumpet the UAH data for May and June. Why?
Every year the UAH data show a substantial drop in May and June. There is a serious seasonal variability in the UAH data, and it seems to be getting worse. For some reason UAH shows a seasonal rise in the anomaly in February, and seasonal decline in the anomaly for May and June. This has been discussed at several blog sites, such as
http://deepclimate.org/2009/06/05/uah-annual-cycle-continues-in-2009/
Interestingly, the UAH data seems to show a much higher seasonal impact than RSS, which only shows a minor seasonal change. Something looks very fishy in the UAH reported data.
REPLY: “Every year you trumpet the UAH data for May and June. Why?”
Paul K lets see how well your argument holds up.
WUWT in May 2007 http://wattsupwiththat.com/2007/05/ – no mention of UAH
WUWT in June 2007 http://wattsupwiththat.com/2007/06/ – no mention of UAH
WUWT in May 2008 http://wattsupwiththat.com/2008/05/ – UAH mentioned because of 4 to .5 degrees C cooler than May 2007 “seasonal anomaly”? Not likely since 2007 didn’t have the same issue.
WUWT in June 2008 http://wattsupwiththat.com/2008/06/ – 1 mention of UAH, due to it being cooler than Hansens 20th anniversary, plus the largest 4 month drop in UAH since 1998
WUWT in May 2009 http://wattsupwiththat.com/2009/05/ – 1 mention of UAH comparing it to RSS at the same time
WUWT in June 2009 http://wattsupwiththat.com/2009/05/ – 1 mention of UAH pointing out the low anomaly near zero
But wait, let’s look at all the other months…if you’ll go through the archives, you’ll see that I mention UAH almost every month since early 2008. I also mention RSS. Trumpeting? Your reporting trend is non-existent, and you’d be the first to jump on me if I made such assumptions on something else without looking at all the data. You don’t like UAH, you don’t like what I report about it, we get it.
Christy offers some insight as to why UAH and RSS don’t always coincide:
http://wattsupwiththat.com/2009/05/07/april-global-temperature-anomalies-rss-steady-uah-dropped-50/
Once again there is a rather large discrepancy between our monthly anomaly (+0.09 deg. C.) and that produced by Remote Sensing Systems (RSS, +0.20 deg. C). We (John Christy and I) believe the difference is due to some combination of three factors:
1) we calculate the anomalies from a wider latitude band, 84S to 84N whereas RSS stops at 70S, and Antarctica was cooler than average in April (so UAH picks it up).
And there’s a good reason why RSS does so.
2) The monthly anomaly is relative to the 1979-1998 base period, which for RSS had a colder mean period relative to April 2009 (i.e. their early Aprils in the 1979-1998 period were colder than ours.)
3) RSS is still using a NOAA satellite whose orbit continues to decay, leading to a sizeable diurnal drift adjustment. We are using AMSU data from only NASA’s Aqua satellite, whose orbit is maintained, and so no diurnal drift adjustment is needed. The largest diurnal effects occur during Northern Hemisphere spring, and I personally believe this is the largest contributor to the discrepancy between UAH and RSS.
Apparently not.
So the real question is, does UAH do a better job than RSS due to platform differences? Does UAH do a better job of representing the planetary temperature than GISS? From my perspective, seeing the issue with weather stations worldwide and the data they produce, and the high number of airports in GISTEMP, I think UAH is free of those biases. Is the “serious seasonal variability” real or an artifact? I don’t know, but I’ll put the question to Dr. Christy.
– Anthony
REPLY: Yes, I asked the question of Spencer, personally I might add. Paul K deserves a few arrows because of the way he acts. Like many of his ilk, he complains loudly but does nothing to advance the actual issue. For the record Paul K was just the troll messenger, not the analyst who pointed out the issue. Paul K gets no respect here. The analyst was another one of those climate cowards that won’t put his name to work, but has plenty to say about how everybody else is wrong.
Despite that, I got the issue advanced due to getting a one-on one meeting with Spencer, even though I thought it might be wrong, I felt the question was valid. And for that, you chide me.
Isn’t trolling under cover fun? You get to say anything like Paul K with no consequences. – Anthony
REPLY: Yes, I asked the question of Spencer, personally I might add. Paul K deserves a few arrows because of the way he acts. Like many of his ilk, he complains loudly but does nothing to advance the actual issue. For the record Paul K was just the troll messenger, not the analyst who pointed out the issue. Paul K gets no respect here. The analyst was another one of those climate cowards that won’t put his name to work, but has plenty to say about how everybody else is wrong.
Despite that, I got the issue advanced due to getting a one-on one meeting with Spencer, even though I thought it might be wrong, I felt the question was valid. And for that, you chide me.
I didn’t chide you for anything, well done for bringing it up with Spencer, he’d been ignoring it for long enough. You backed the wrong horse with your headline on that occasion, it should have been “UAH for June – way out there”, something that had been apparent for a few years.
Isn’t trolling under cover fun? You get to say anything like Paul K with no consequences. – Anthony
No trolling, I’d been pointing out the problems with the UAH spring results for some time after reading Swanson’s GRL paper.
REPLY: I’ll never understand why you think GISS is a reliable measure of temperature. Talk about backing a wrong horse. At least UAH fixes problems, GISS still can’t get the signs of adjustments right after being pointed out in dozens to hundreds of station examples. – A
Wow! If such adjustments would have been necessary for NASA’s data, there would have been no end to the cries of conspiracy!
Caleb (07:29:57)
Thanks for your helpful reply. Some interesting food for thought. I also feel that the deep ocean needs to be brought in for any chance of a working understanding of climate patterns. Bob Tisdale’s work in this area is indeed important.
A new UAH temperature record for march seems very likely inspite of the new calculation which reduces the march values slightly. The old one from 1998 (+0.54) is not affected by recalculation. At least the absolute record values (+0.76) from february and april 1998 are not in danger.
Why waste time arguing about the short term ups and downs, which data source is best and what minor corrections have been applied here and there? UAH is up this month and will be down again sometime in the near future. The big picture is what really matters and that shows that the global temperature is definitely on a long term upward trend – all of the data sources show that to clearly be the case.