NASA Aqua Sea Surface Temperatures Support a Very Warm January, 2010
by Roy W. Spencer, Ph. D.
When I saw the “record” warmth of our UAH global-average lower tropospheric temperature (LT) product (warmest January in the 32-year satellite record), I figured I was in for a flurry of e-mails: “But this is the coldest winter I’ve seen since there were only 3 TV channels! How can it be a record warm January?”
Sorry, folks, we don’t make the climate…we just report it.
But, I will admit I was surprised. So, I decided to look at the AMSR-E sea surface temperatures (SSTs) that Remote Sensing Systems has been producing from NASA’s Aqua satellite since June of 2002. Even though the SST data record is short, and an average for the global ice-free oceans is not the same as global, the two do tend to vary together on monthly or longer time scales.
The following graph shows that January, 2010, was indeed warm in the sea surface temperature data:
But it is difficult to compare the SST product directly with the tropospheric temperature anomalies because (1) they are each relative to different base periods, and (2) tropospheric temperature variations are usually larger than SST variations.
So, I recomputed the UAH LT anomalies relative to the SST period of record (since June, 2002), and plotted the variations in the two against each other in a scatterplot (below). I also connected the successive monthly data points with lines so you can see the time-evolution of the tropospheric and sea surface temperature variations:
As can be seen, January, 2010 (in the upper-right portion of the graph) is quite consistent with the average relationship between these two temperature measures over the last 7+ years.
[NOTE: While the tropospheric temperatures we compute come from the AMSU instrument that also flies on the NASA Aqua satellite, along with the AMSR-E, there is no connection between the calibrations of these two instruments.]
JP I’m glad you found the post useful. It has been long enough since I worked in this area that I couldn’t confidently say how to get the raw data — just asking for it today may well alarm people given the political issues involved. It may need an official FOI request to pry the raw sensor data loose and also to find out how the computer programs have changed over the years. One other point occurred to me after writing the previous post –that by relying on an expected average set of temperatures for the atmosphere at a given time and place, the satellite measurements in effect assume a steady climate (climate being broadly defined as average weather) and use that assumption to estimate each day’s temperatures as a relatively small deviation, mathematically speaking, from the expected climate. This not only makes the satellite temperatures vulnerable to changes in the computer programs’ assumptions about the climate, it also makes the satellite temperatures a relatively bad way to measure climate change of any sort, since the computer programs are always, until told otherwise, assuming **exactly** no climate change. I guess this means that, from the climate alarmists’ point of view, satellite temperatures could be expected to show less of a temperature rise over the last several decades than the surface data does. From the point of view of the rest of us, it would be nice if CRU had not lost the raw data and if NOAA had not decided over the last 15 years or so to stop taking measurements from weather stations located at high altitudes and above the arctic circle. From an objective point of view, it may still make sense to look for trends in the satellites’ raw heat-radiation data, and find out whether the satellite software has changed over the last thirty years. Vigilantfish’s story about how the satellites missed the developing polar ozone hole is also very relevant, because (although I’ve not worked with ozone detection) the mathematics of measuring ozone from its effect on the radiation leaving the earth’s atmosphere would almost certainly be another type of ill-posed problem — so it too would have to be solved by starting out with some restrictive assumptions about the sort of ozone layers the satellite is looking at.
tallbloke: You wrote, “…and cloud has been increasing.”
And if memory serves me well, the complaint about the early ISCCP cloud amount data was the noise created by volcanic aerosols. Is there something to combat that dataset now that comes to mind?
It’s a good idea to step back and look at what the numbers actually mean; and in this case, they are departures from the mean over a previous, longer period. (I hate the term “anomaly” because it has connotations of wrongness.) So the January figure tells us only that it’s warmer than what one would expect if there were no change.
Instead of an actual increase in mean temperature, such a “warming” could simply mean that it’s not cooled as much as the mean. Several factors can explain such a “lack of cooling”; the most likely that springs to mind is increased cloud cover.
One can’t know for sure without reference to the absolute temperatures instead of departures from the mean in conjunction with the global insolation data for the relevant periods.
Paul Vaughan (12:17:43) : “Substantially more investment in research into natural climate variations is needed so we can get off these ridiculous political distortion cycles that track every bump & dip in climate.”
Hear hear.
Chris
Norfolk, VA, USA
Symon (18:18:17) : You wrote, “Bob, I don’t get it. Is the whole planet warmer this month than it has been for a few decades? Because the sun has been in a funk.”
First, a clarification: The record lower troposphere temperature (TLT) anomaly is for the month of January. According to the preliminary reading (0.724 deg C), it is not an “all-time” record TLT anomaly. February and March 1998 readings were higher at 0.76 deg C.
Second, other bloggers are claiming the extended solar minimum is causing the oceans to release heat and warm the atmosphere. Not me. I can very simply point to the facts that the 1997/98 El Nino caused an upward step in the TLT anomalies of much of the Northern Hemisphere. I’ve discussed it here:
http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html
A similar but smaller upward step occurred as a result of the 1986/87/88 El Nino.
Bob Tisdale (17:49:26) : [Dr. Spencer] .. would be the person with the answers to your questions.
I don’t wish to make this a question for the AMSU series or any particular researcher.
I’d prefer to ask questions of the science in the open and to receive open replies. Any potential issue here should already have been answered in the scholarly literature.
Methods to removing the possibility of artifacts due to aliasing should be addressed in statements of methodology, and perhaps analysis included in SI to relevant papers.
But we do have an absolute requirement set out for us in the sampling theorem, and this will limit the scope for any suggestions of novel approaches, or sweeping inadequate data into statistical averages and hoping that everything will be OK.
Jones et al presents a temperature series going back some 150 years. His series has been elevated to the status of the “instrumental record” and claimed to be superior to proxy data. But his analysis seems to be of a statistical nature, and there is no obvious statement about how he has complied with the sampling throrem for the last 150 years. Not just achieving the theoretical minimum sampling condition, but exceeding it by a a factor of around 10 in order to be able to accurately reconstruct climate patterns.
Not to forget that the shape of those series must be attributable to real physical processes. If fluctuations are swept under the carpet as “random variations”, you should look upon them as equivalent to those backward-spinning wagonwheels in old movies.
Aliasing must be designed-out of the system as a principal objective of the sampling strategy. If you do not feel satisfied that this has been achieved, the safest thing to do is to ignore the shape of these putative climate signals.
the brightness anomaly for january-
http://www.remss.com/msu/msu_data_monthly.html
shows a large red blob over china. including the sea ice off the coast which is set to get worse soon –
http://www.china.org.cn/environment/2010-02/05/content_19372251.htm
it is obvious when it reads sea ice as a red blob where previously this did not exist even in the life of the satellite, there is something wrong with the calculations made regarding snow and ice.
australia temp anomalies are incorrect too, they should show cooling in the top half, but only show warming in the lower.
the problem of snow/ice should not influence australia, so the question is why?
i could understand that because of the fact that AMSU are microwave frequencies and snow and ice are rather transparent to them as compared with water, that snow or ice may be miscalculated due different types of snow crystals etc and snow where there was none before, or even sea ice where there normally is none, but why is australia showing no cooling? base period perhaps?
Jordan (02:24:34) :
“Any potential issue here should already have been answered in the scholarly literature.”
Indeed it has. First, there are some serious misunderstanding by commentators on this site about the Nyquist theorem. The theorem states that if signals are sampled at twice the maximum frequency present in a signal, that signal can be perfectly determined. It does not say anything about the average of that signal, and that can be very well, but not perfectly, determined from much fewer points: you don’t need to know every point on the ocean floor to determine its mean depth of 12400 ft to the nearest 100 ft.
Dr Roy Spencer measurements are on a 2.5 x 2.5 deg grid, or at a spacing of about 250 km. Hansen and Lebedeff looked at the variation in temperature anomalies with spatial frequencies back in 1987:
http://pubs.giss.nasa.gov/docs/1987/1987_Hansen_Lebedeff.pdf
and concluded that sampling at 1000 km was sufficient to plot the anomaly variation.
“Sorry, folks, we don’t make the climate…we just report it.”
Not to nitpick but one month of temperature data at 14,000 ft is hardly climate.
The CO2 hypothesis suggests that the oceans are warmed by the troposphere which traps heat near the surface. So it should be noted that any explanation showing that warming of the troposphere in January is caused by ocean heat does not support this hypothesis, and can be written off as natural variability due to an El Nino effect.
As for why the ocean warming (SST) translates into higher temperatures at 14,000 ft and not over land is beyond me. In the NH I believe oceans (excluding sea ice) cover not much more than 60% of the surface, and it would seem the higher amounts of snow cover in January would reflect more sunlight back to space, and perhaps to clouds at 14,000 ft?
Since global temperature data only goes back a few years,
one more little tidbit from Prof. Ole Humlum’s (University of Oslo) website at Climate4You:
The Spanish Armada (Jul-Aug 1588) and the Winter of 2007 –
“From an official English political point of view the outcome was a major triumph for the English Navy and for Sir Francis Drake. In reality it was a climate-induced disaster for Spain and King Philip II, who rightfully complained that he had sent his ships to fight the English, not the elements. The immediate political effect was the survival of the Kingdom of England and the gradual transfer of world sea dominance to the British Navy: Rule Britannia, Britannia rules the waves.
“From a meteorological point of view the strong westerly and north-westerly winds suggest a major storm centre travelling across England, in response to a relatively southerly position of the Polar Jet Stream. Presumably the meteorological situation was much alike that bringing about the wet, windy and cold summer of 2007 in NW Europe.”
http://www.climate4you.com/ClimateAndHistory%201500-1599.htm
Mea Culpa –
The Spanish Armada (Jul-Aug 1588) and the “Summer” of 2007
Symon: You wrote, “I’d prefer to ask questions of the science in the open and to receive open replies. Any potential issue here should already have been answered in the scholarly literature.”
Have you searched the scholarly literature written about this and the RSS MSU TLT anomaly dataset to see if your questions have been addressed?
pft (06:08:04) said:
The Sun inputs some 1600 W/m2 of energy into the oceans (although averaging reduces this). How much does can the atmosphere input?
Secondly, what is the heat capacity of the oceans vs the heat capacity of the atmosphere? Which has the greater thermal inertia?
Frankly, the atmosphere has little ability to impact the temperature of the oceans, and as someone else said, perhaps on another thread, any temperature excursion of the lower atmosphere is going to be dragged back to the temperature of the sea surface in short order with little impact on ocean temperatures.
R. Gates (12:03:15) :
The whole month of January is hardly a single data point. Now, If it had been a single day that was warm, that would be different. Janauary had 31 data points as days. Last I checked the year was made up of 12 months, and now we are more than 1/12 the way the way through the year and temperatures are still high througout the troposphere from sea level up to 46,000 ft. Now that’s a pretty big “single” data point.
I must have missed something. I don’t seem to recall R. Gates posting back in June that there were 30 days making a “big” data point. Of course, the fact that the anomaly was .003 may have been the reason. Now, if we extrapolate from that point we’d already be starting the next ice age.
Clearly, R. Gates does not want to discuss science. You’d think the other warmers would jump on him, since he’s making warmers in general look bad.
Picking up on mobihci (04:58:38) : point, we do seem to be seeing major discrepancies from satellites, even in simple Photos. As I have posted before Satellites do not appear to be showing non Artic Ice in the NH.
I also agree that “Sorry, folks, we don’t make the climate…we just report it.” was not a completely truthfull remark, they are not even reporting weather, just an Interpretation of electrical signals.
I would prefer to rely on Mercury or Alcohol.
Do we still have Weather Balloon readings being taken?
The sudden rise of the UAH LT anomaly for the month January 2010 was unexpected to me. Let us concentrate on the Nothern Hemisphere, where we ascertained an anomaly of +0.841deg. C.!
We all had the impression that it was much colder in last January than normally. Is it possible that the satellite didn’t notice the cold layers of air above land? I don’t believe it (unless the reflection by the snow plays a role). So, this means that the rise of temperature of the sea surface must be very high. How is this possible on a hemisphere with 60 procent of sea and 40 procent of land? If the temperature anomaly on land is negative, then the anomaly above sea has to be very high. Example: (- 0.24 * 0,4) + (+1.56 * 0.6) = 0.84 deg. C.
Is it possible that the temperature anomaly above sea in the Northern Hemisphere was +1,56 deg. C. in January?
I think scientist have hardly notion of the partition of temperature in and above the ocean. Do they know exactly what the satillite is measuring and at what height? I agree with the statement that there is a relation between SST and tropospheric global temperature, but it seems to me that the temperature above land hardly plays a significant role.
I have also questions about the high fluctuations of the temperature anomaly ascertained by UAH (or RSS). Certainly, El Nino is a factor in the discussion, but not exclusively. In the years 2002 to 2007, we ascertained high anomalies with a moderate El Nino. Even in the month December 2009, the value of ONI (ERSST v2) was 1.8, not the value 2.5 of December 1997.
We can hope that this time again, the sudden rise will be followed by a proportional decline. Only, it is possible that the expected decline will not happen in the first months. The average anomaly (UAH) for the month February from 1998 to 2009 is + 0.352 deg. C. (for the month January, the average from 1998 until now is + 0.336 deg. C.). Wait and see…, but an anomaly of such amount as in January 2010 has to be kept in mind.
R. Gates (12:03:15) :
Don’t worry about ice loss at the poles. The sun never gets past the Bragg angle of 57° and so heating, whether of water or ice, is minimal.
This could also simply mean that winds over the ocean were lower than the mean for January. SST as I understand it are strongly effected by evaporative cooling due to average winds.
In theory the prevailing winds are driven by temperature differentials between the equatorial ocean and the poles. If that differential temperature narrows, prevailing winds would decline in strength and duration on average. That reduced windiness, would reduce evaporative cooling. Reduced evaporation would lower average humidity and cloudiness.
It would be interesting to see a tabulation of average cloudiness and winds over the oceans during this same period to see if that might explain warmer than average oceans while the northern hemisphere land masses were cooler than average.
Larry
Take note of Joe Bastardi’s view on the matter:
http://www.accuweather.com/ukie/bastardi-europe-blog.asp?partner=rss
Bob Tisdale (02:11:59) :
You are right about the upward steps in 97 (or 95, and 77), not so sure about the 87 though, ok, a very small one. Anyway, the problem is it doesn’t drop back enough before the next step. Bacause of an underlying trend?
http://virakkraft.com/ohc-tropics-enso.png
… or because the steps are to frequent?
Bob Tisdale (18:35:41) : “Tom in Florida (12:41:14) : Will someone please make the definite statement that when SST goes higher it is either:
1. due to the release of heat from the oceans and they are cooling
2. due to the accumulation of heat in the ocean and they are warming
Which is it?
************
It depends on the time frame.”
So are you saying that simply charting a monthly SST anomaly doesn’t tell you anything specific about the direction of global temperature trends?
R. Gates (12:03:15) :
R.Gates,
I don’t see how anyone can state with any degree of confidence that a diminished, or even missing, arctic ice cap would be good or bad or anything for the ecological balance of the planet.
For example, what was the status of the northern ice cap when the Vikings were raising wheat and cattle in Greenland? I don’t know the ice extent, of course no one does, at that time. But I think it would be reasonable to conclude the arctic ice extent was much smaller in 1000 AD than today.
Was there suffering on the part of the human family during the medieval warm period? Of course not. It was a time of great prosperity, with food surpluses and spare time for society as a whole. As people were of a religious bent in those days, we saw the building of the Gothic style cathedrals.
It was only when things got cold everyone began to suffer. Apparently the last of the Vikings died in Greenland around 1500 AD.
No doubt when it began to get colder, the Arctic ice cap expanded.
tallbloke (13:02:48) :
The first one. I’ve been saying it for a year now. The ocean heat content is dropping, because the amount of solar energy going into it has been falling since 2003, and cloud has been increasing.
The ocean responds by releasing the heat built up over the long run of high solar cycles, keeping the global temperature up.
Why when it’s cooling would it release more heat. Surely some sort of equilibrium would would be established between the ocean and the atmosphere. If the oceans were cooling relative to the atmosphere surely there would be less heat transferred upwards.
I genuinely don’t understand your point.
There was a huge, very intense warm pool in the Southern Ocean, halfway between New Zealand and Tierra del Fuego, that persisted throughout most of January. Methinks that’s what spiked the monthly anomaly. It has little to do with the faux El Nino (aka Modokai) and even less to do with all the other causes speculated here. Underwater volcanism, anyone?