This is just for our friends in Europe and Australia…or anyone traveling there.

(UPDATE: added Asia and South America, too.)

In our first foray into non-U.S. weather, I’ve added 10-day GFS model forecast animations to WeatherStreet.com. My personal favorite is the air mass temperature (850 mb) forecasts:

Europe 850mb Temp & winds (looks like quite a blow coming thru the UK next Monday)

Australia 850 mb Temp & winds

Asia 850 mb Temp & winds

South America 850 mb Temp & winds

Other forecast fields have links from the above; mouseover the blue bar to animate.

The model field graphics are from Unisys weather…we just make them easier to visualize.

Craig Idso, an expert on the fertilization effects of elevated CO2 levels on various plant species, has done a new study of the positive externality (unintended economic consequence) of increasing CO2.

In the 50 year period, 1961-2011, he estimates that there has been a $3.5 trillion benefit resulting from increased agricultural productivity. The projected benefits in the coming decades are even larger.

Egad! How could any by-product of human activity possibly be good? That sure wasn’t what I was taught in school!

In our modern age of self-flagellating hand-wringing do-gooders with too much time on their hands and anxious to find some cause to convince others to pay for assuaging their self-imposed guilt (phew), it is seldom we hear any good news about anything related to climate change.

And if just the agricultural benefits of increasing CO2 is in the multi-trillion dollar range, what about the prosperity enabled over the last 100 years by access to abundant, affordable energy? How many gazillions of dollars would that be?

Yet, the government continues to try to justify a wide range of regulations punishing the use of fossil fuels based upon the silly idea of “social cost of carbon” (SCC), the supposed overwhelming negative externalities resulting from fossil fuel use.

When are real economists with some gonads going to stand up for the social benefits of carbon (SBC)? People like Matt Ridley are speaking out on the subject. Where are the economists? Have they (like most climate researchers) been bought off, too?

Until we get an unbiased accounting of BOTH costs AND benefits of using fossil fuels, there is little hope in getting rational public policy that won’t do more harm than good.

I’ve been watching the 10-day GFS forecast for the U.S., and each run is reinforcing the previous one, with a major cold air outbreak for most of the U.S. late next week:

I’m reminded of when I started the graduate program in meteorology at UW-Madison in the fall of 1978. We were getting an unusual string of cold fronts which all the professors were claiming could not last. Eventually, warmer Pacific air would come in from the west…it always does.

Except during winter ’78-’79…it didn’t. The cold air just kept coming.

I’m not making a winter forecast here…just reminiscing. But I will say that I’ve been watching the model forecasts nearly every day for decades (since I’m co-developer of WeatherStreet.com, and still a weather weenie at heart), and for many years the model forecast tendency has been to over-forecast these cold air outbreaks.

The model would predict a cold front coming through our neck of the woods (N. Alabama) 5-7 days in advance…but the front would almost never make it, or it would not plunge as far south (or be as cold) as originally forecast.

But this model error tendency seems to have changed in the last couple years, with that cold air not only making it, but reaching the Gulf coast and beyond. This has been a record cold summer in Alabama, and we had cool fronts pass through regularly all summer long. I don’t recall that ever happening in the 30 years we have lived here. The lawn stayed spring-green all summer, when usually we have to work to keep it alive.

Maybe my friend Joe Bastardi will chime in and say whether he has seen a similar change in the model error in recent years.

At least we can be thankful that when the cold air does arrive, it will be slightly warmer than it would have been without global warming. Ha-ha.

I was working up some global comparisons between the CMIP5 models (provided by the KNMI Climate Explorer via John Christy) and the HadCRUT4 surface temperatures, as well as our UAH lower tropospheric temperatures.

And I think I discovered what the IPCC meant regarding 95% certainty and global warming. I’m sure it was an honest mistake on their part.

As seen in the following graphic, over the period of the satellite record (1979-2012), both the surface and satellite observations produce linear temperature trends which are below 87 of the 90 climate models used in the comparison.

So, about 95% (actually, 96.7%) of the climate models warm faster than the observations. While they said they were 95% certain that most of the warming since the 1950s was due to human greenhouse gas emissions, what they meant to say was that they are 95% sure their climate models are warming too much.

Honest mistake. Don’t you think? Maybe?

I’m far from a political moderate, but I’ve been tagged as a “lukewarmer” in the climate wars. That’s because, at least from a theoretical perspective, it’s hard (but not impossible) for me to imagine that increasing CO2 won’t cause some level of warming.

I would remind folks that the NASA AIRS instrument on the Aqua satellite has actually measured the small decrease in IR emission in the infrared bands affected by CO2 absorption, which they use to “retrieve” CO2 concentration from the data. Less energy leaving the climate system means warming under almost any scenario you can think of. Conservation of energy, folks. It’s the law.

But I’ve been troubled for quite a while by those “skeptics” (you know who you are) who are forecasting cooling in our future. Not that it couldn’t happen, but are you ready to be “debunked” when we see continued slow warming?

The debate will then be about how the skeptics who predicted cooling were wrong. Warming continues. The IPCC was right. There is obvious danger in that becoming the narrative.

Some of us have been trying to explain that there is a big difference between weak (or even modest) warming, and catastrophic warming. The former is probably beneficial, especially when you factor in the benefits of more CO2 on photosynthesis. I was taught this lesson by Pat Michaels who, after my talk at a Heartland conference, correctly rebuked me for publicly implying that modest warming would be evidence the IPCC was correct and we skeptics were wrong.

Pat was right. Some level of warming can probably be expected, but just how much makes a huge difference. Lindzen and I and a few other researchers in the field think the IPCC models are simply too sensitive, due to positive feedbacks that are either too strong, or even have the wrong sign. But we still believe more CO2 should cause some level of warming.

If the current lack of warming really is due to a natural cooling influence temporarily canceling out CO2-induced warming, what happens when that cooling influence goes away? We are going to see rather rapid warming return…but nowhere near the levels of warming predicted by most of the IPCC climate models.

It’s fascinating to me that the predictions we see in the media are almost bimodal…either catastrophic warming, or another ice age. Of course, the news cycle enjoys predictions of catastrophe (see the Time magazine covers, above).

But sometimes it seems like we global warming moderates are getting drowned out by the extremists.

(And for those who are ready to snark me for my “extremist” political views, I will only say that it’s a sad day when supporting the U.S. Constitution is viewed as “extremist”.)

So, I have apparently opened a can of worms with my challenge to Willis Eschenbach to read up on subjects a little more before he claims to have invented something new. Unfortunately, Willis took my post as a swipe against citizen scientists, which it wasn’t. As I said, I “applaud” people who are willing to get their hands dirty with the data. I also said I consider Willis a very sharp guy, and he is a gifted writer.

Anyone who read my post could see I was not faulting citizen science. (My showing a sharp-looking Homer Simpson as a citizen scientist was insulting, but showing professional scientist Jim Hansen being arrested wasn’t? C’mon.)

For example, Anthony Watts (who is a meteorologist) has forced NOAA to quit pretending it has pristine surface temperature data, and has helped reveal what a mess the surface thermometer adjustments have become (the adjustments are *always* in the direction of more warming? Really? [btw, that’s a criticism of NOAA’s adjustments, which always seem to produce more warming]).

Similarly, Stephen McIntyre (along with Ross McKitrick) have shown that if you analyze tree ring data and statistically *assume* there is a hockey stick shape to the data, you will get a hockey stick shape to the data. (Sorry if I’m oversimplifying what Steve has shown).

Now, both Anthony and Steve have formal technical backgrounds, which I don’t believe is necessary… a person can be self-taught, which is what Willis is. And that’s fine.

But in Willis’ case, as far as I can remember, he has not revealed anything that we did not already know. Now, that’s fine if this is just a part of Willis’ personal education. But over the last several years he has put forth ideas which he has claimed as his own, when in fact they have been previously published…even leading to multi-agency field experiments in the case of “his” Thermostat Hypothesis.

In science, you find out what has been done before, and then you either build upon it or show where it is wrong and do it differently. And, you don’t advance as your theory what has been done before.

Why should I care what Willis does? Because the way he presents his analysis leads readers to assume that what he is presenting is new, when in general it is not. *I* then have to deal with e-mails asking what I think about “his” latest theory. I have to explain to people that either “we already knew that”, or “that data plot doesn’t demonstrate what he claims, and here’s why”.

This is not a new problem, and I have blogged on it before. Now, since I have been talking in generalities, and Willis has asked for specifics, here we go again (I have covered some of this ground before)…

The Thermostat Hypothesis
In 1991, Ramanathan and Collins advanced in Nature their theory of surface temperature regulation by deep moist convection in the tropics. This became known as the “Thermostat Hypothesis”, which led to a field experiment (CEPEX, 1993). Yet, on WUWT, you will find Willis talking about the Thermostat Hypothesis as being ‘his’ theory. For scientists, this would be a major faux pas.

Of course, moist convection on average cools the surface of the Earth…even Kiehl & Trenberth’s much-maligned global energy budget diagram shows this average rate of cooling to be about 100 W/m2, compared to an average solar input of 240 W/m2. But how convection might change in a global warming scenario (i.e., its regulation ability) is a very complex topic, and one which has been studied for decades by hundreds of scientists. Willis is just scratching the surface of a very large body of existing knowledge.

For example, even climate models say convection will increase with warming, leading to even more surface cooling…yet, the models still amplify the warming. This is because surface evaporative heat flux is only one of a myriad influences on the surface energy budget, and therefore on surface temperatures.

Now, the Thermostat Hypothesis might just be a case of Willis not doing his homework first. And if Willis figured out this theory on his own, why should I care?

Because it leads to the mistaken impression among readers (read the comments on WUWT) that professional climate diagnosticians are too stupid to figure out what this citizen scientist has done, when in fact it *has* been done before. This puts me in the VERY unusual position of defending mainstream climate scientists…and, as my readers know, most of the mainstream have disowned me. But I will give credit where credit is due, and mainstream climate scientists have learned (and published) a lot over the years…some of them just have a bad habit of claiming silly things like “proof” and “95% certainty”.

Again, I am not against citizen scientists figuring out something new. But don’t give people the impression that this stuff hasn’t been done before, unless you are familiar with the literature and know that to be the case.

Instead, build upon what we already know. Anybody who can download a dataset and plot graphs in Excel can claim this or that about what the graph means. But it is rare that anyone discovers something new and significant; almost always the data can be explained based upon what we already know.

Some think I am being harsh in my criticism. But After years of having to answer questions about Willis’ latest ideas, I frankly don’t know what else to do. I have previously tried to keep it low key.

I don’t want to dissuade Willis from contributing to the science. But contributing to the science requires more due diligence than plotting graphs and leaving readers with the impression that the graphs show something new or unexplained (in this case, demonstrating the differing water vapor greenhouse effect between tropics and high latitudes, and the fact that the tropics export heat to the high latitudes).

Willis, you write really well, you are a smart guy, and you can make complex subjects more understandable. Don’t dilute those talents by leaving readers with the wrong impression.

I don’t usually respond to public policy commentaries written by scientists. Everyone is entitled to their opinions…even scientists.

But Andy Dessler and Jerry North, both Texas A&M professors and climate researchers, felt the need to lecture the rest of us about the certainty of manmade global warming, and that if we just trust the government, a solution will be found.

Yeah, they pushed my button.

Sure, the Clean Air Act did a lot of good (to an extent), and with the Montreal Protocol we found new refrigerants to replace traditional chlorofluorocarbons, as Dessler and North correctly point out.

But this is like saying, because we found a cure for smallpox, we can certainly find a cure for aging.

In fact, just outlaw aging. There, problem solved.

Or, if we try hard enough, we really can put a teletransportation device in every home, and harness the limitless energy potential of antigravity.

Sorry, but not all medical or engineering problems are created equal. Have Dessler and North not been paying attention to what is happening in Europe, especially the UK? “Renewable” energy has proved so expensive and unreliable that they are facing another winter with the threat of even more people dying due to prohibitively expensive energy.

Dessler and North can pontificate from their cushy, federally-funded (and Texas state oil-money funded) jobs, but to at least half the citizens in the U.S., they appear clueless and elitist. The wealth they enjoy did not come from the government, but from the private sector, which is where prosperity is created and where money derives its purchasing power.

They can afford more expensive energy; many people can’t.

Even if humans are responsible for the warming of the last 50 years, there is little that can be done about it in the near term. The global demand for energy is simply too large to meet with renewable sources, which even with a bust-gut effort will only amount to about 20% of global energy needs in the coming decades.

And when new energy solutions do come, they will more likely come from the private sector, not government. Energy is needed by everyone, and energy companies are working on alternatives to fossil fuels. Traditional energy sources are indeed finite, so as they become more expensive to find and extract, prices will rise, and alternatives will be eventually developed to replace them.

In the meantime, it would appear that Dessler and North would rather punish energy use, destroy prosperity, and kill poor people.

How can I make such an accusation? Well, how else can you explain Dessler and North hiding the fact that global temperatures stopped rising 15 years ago, in contradiction to most, if not all, IPCC climate model forecasts?

They could have said, “The lack of warming is good news for humanity! Maybe global warming isn’t a serious problem after all!” Or even, “We have more time to solve the problem!” But, no.

Instead, they do exactly what they accuse Republicans of doing…letting their views of the proper role of government (and their desire for more climate research funding) determine what they believe (or profess to believe) about the science.

Since Dessler and North want more government, not less, they ignore the inconvenient truths about global warming not being as big a problem as the IPCC forecasted it would be.

So, stick to the ivory tower, guys. Better to let the people who work to support you wonder about your cluelessness, rather than open your mouths and remove all doubt.

I’ve been asked to comment on Willis Eschenbach’s recent analysis of CERES radiative budget data (e.g., here). Willis likes to analyze data, which I applaud. But sometimes Willis gives the impression that his analysis of the data (or his climate regulation theory) is original, which is far from the case.

Hundreds of researchers have devoted their careers to understanding the climate system, including analyzing data from the ERBE and CERES satellite missions that measure the Earth’s radiative energy budget. Those data have been sliced and diced every which way, including being compared to surface temperatures (as Willis recently did).

I’m not defending the IPCC’s use of climate models here. I’m talking about climate diagnostic work with real satellite data…figuring out how the climate system works from observations.

I’ve previously commented on Willis’ thermostat hypothesis of climate system regulation, which Willis never mentioned was originally put forth by Ramanathan and Collins in a 1991 Nature article. Basically, it has been known for a long time that moist convection has a huge cooling effect on the surface of the Earth (e.g. Manabe and Strickler, 1964), but the fact that deep moist convection tends to occur over the warmest tropical waters doesn’t really tell us anything about the sensitivity of the climate system or cloud feedbacks.

Take Willis’ latest posts about the “cloud radiative effect”, which formerly had been called “cloud radiative forcing”. All you have to do is google “cloud radiative forcing” (choose image results if you want lots of pretty pictures) to see that many scientist-years have been devoted to analyzing such data.

If you want to get some idea of what has been done on cloud feedback, then a good place to start is Graeme Stephens (2005) review of cloud feedback work performed over the years.

The reason I am picking on Willis a little bit here is that his posts sometimes lead to comments like this:

“Geez – if I was one of the hoard of IPCC enthusiastic fools, this would be downright embarrassing. I sure wouldn’t want my mom to know I was so ineffective that some guy named Willis sits in his den and does more and better work than my entire IPCC crowd of hundreds of scientists, economists, psychologists, train engineers, tree surgeons, etc does in 4-5 years.”

C’mon, folks! Do you really think that of the billions of dollars spent on designing, launching, and keeping these satellite instruments going, that no one thought to analyze the data? Really? That’s why hundreds of scientists and engineers collaborated on such projects in the first place!

Just because you can’t find some technical issue described in blogs doesn’t mean it hasn’t been addressed. It’s in the scientific literature, and in workshop reports, conference proceedings, etc.

In retrospect, it’s now clear that public interest in climate change has led to citizen-scientists like Willis taking matters into his/her own hands, since so little information is available in a form that is easily digested by the public. Career scientists like myself have not done enough public outreach to describe what they have done. And when we do such outreach, it is usually too technical to understand. We are too busy publishing-or-perishing.

As a result, just about every time someone posts an amateur analysis of data that becomes popular, I’m asked to read it, critique it, and respond. Well, I simply don’t have the time. But these things sometimes get legs, and when they do, I get even more e-mails.

For example, I still get the occasional e-mail because the Sky Dragon Slayers took a NASA report about CO2 cooling of the upper atmosphere (which we have known for at least 50 years) and spun it into ‘proof’ that CO2 can’t warm the lower atmosphere. Well, greenhouse gases cool the upper layers, and warm the lower layers, of planetary atmospheres. Nothing new there…except maybe to misguided public perceptions of the science, which usually only involve the warming effects of greenhouse gases.

Anyway, I applaud Willis, who is a sharp guy, for trying. But now I am asking him (and others): read up on what has been done first, then add to it. Or, show why what was done previously came to the wrong conclusion, or analyzed the data wrong.

But don’t assume you have anything new unless you first do some searching of the literature on the subject. True, some of the literature is paywalled. Sorry, I didn’t make the rules. And I agree, if research was public-funded, it should also be made publicly available.

But cloud feedback is a hard enough subject without muddying the waters further. Yes, clouds cool the climate system on average (they raise the planetary albedo, so they reduce solar input into the climate system). But how clouds will change due to warming (cloud feedback) could be another matter entirely. Don’t conflate the two.

For instance, let’s say “global warming” occurs, which should then increase surface evaporation, leading to more convective overturning of the atmosphere and precipitation. But if you increase clouds in one area with more upward motion and precipitation, you tend to decrease clouds elsewhere with sinking motion. It’s called mass continuity…you can’t have rising air in one region without sinking air elsewhere to complete the circulation. “Nature abhors a vacuum”.

So, examining how clouds and temperatures vary together locally (as Willis has done) really doesn’t tell you anything about feedbacks. Feedbacks only make sense over entire atmospheric circulation systems, which are ill-defined (except in the global average).

And we already knew that clouds, on average, cool the climate system, as described almost 25 years ago from the first Earth Radiation Budget Experiment (ERBE) data.

I consider what follows to be potentially very significant…but also very preliminary.

Background
Global warming (including the increase in ocean heat content) is supposedly explained by human greenhouse gas emissions (CO2) reducing the ability of the Earth to cool through infrared radiation to outer space, leading to the observed warming in the last 50 years or so.

My (admittedly minority) view is that some portion of this heating/warming is due to Mother Nature, probably from natural cycles in low cloud cover changing the amount of sunlight absorbed by the Earth. (Why? Well, take your pick…ENSO, PDO, NAO, cosmic rays, etc.).

So, which is it? Are humans keeping the Earth from cooling by reduced infrared energy loss, or is nature causing warming from extra solar energy gain? Or both? I’ve maintained it’s a mixture of both, in unknown proportions.

The answer would be much more obvious if we had accurate measurements of global absorbed sunlight and emitted infrared radiation over a long period of time. But we don’t. What we have, and only since 2000, is reasonably precise measurements of the month-to-month variations in these energy flows (from the NASA CERES instruments)… the absolute accuracies are not good enough to measure the (presumed) anthropogenic heating effect of more CO2 in the atmosphere. The ERBE satellite measurements before that time are rather spotty and much more uncertain.

What we need, if possible, are other observation-based surrogates for global radiative energy flows.

SSM/I Oceanic Cloud Water: A Surrogate for Net Radiative Energy Fluxes Back to 1987
We now have over 25 years of SSM/I (and SSMIS) oceanic cloud water measurements, from Remote Sensing Systems. The monthly departures from average (in percent) through August, 2013 look like this:

I’ve compared these cloud water variations to CERES radiative flux variations (both over the global ice-free oceans, between March 2000 and June 2010), and there is a pretty good relationship:

The correlation coefficient is 0.72, and the regression line shown is a 2-way fit.

If we take this regression relationship, and convert the SSM/I cloud water variations in the original plot to Net radiative flux variations, we get the following plot:

Now we can sum up these monthly average flux variations over time, and over the area of the global ice-free oceans (~341 million sq. km.), to get energy accumulation in 10**22 Joules, and compare it to one estimate of the increase in ocean heat content:

Taken at face value, this plot shows that about 1/3 of ocean heating over the 20-year period from 1990-2010 can be accounted for just based upon a change in oceanic cloud cover alone, probably a decrease in low clouds. (I say probably a decrease in low clouds because the SSM/I and SSMIS instruments only measure cloud water, not cloud ice which is transparent at the 19.35 and 37 GHz microwave frequencies. The CERES comparison I did vs. cloud water showed that most of the relationship was in the reflected shortwave [sunlight], not emitted longwave [infrared], which is consistent with a low-cloud effect rather than high-cloud.)

What Does All This Mean?
I think it is additional evidence that natural cloud variations cause multi-decadal time scale climate change.

But how do we know that this isn’t just positive cloud feedback on human-caused warming? Well, first of all there has been virtually no surface warming over this period of time, and cloud feedback is (by definition) in response to surface temperature.

Secondly, since about 2010 we see there has been an abrupt reversal in the trend of ocean energy accumulation…basically wiping out the energy accumulation caused by the previous 20 years of reduced cloudiness. Did positive cloud feedback suddenly change to negative cloud feedback? Seems hard to believe.

The more logical explanation is that there are natural cycles in cloud cover which cause multi-decadal periods of global warming or global cooling.

It will be interesting to see if the SSM/I-inferred changes in Net radiative flux after 2010 are supported with more recent CERES data (my CERES dataset only extends through June 2010). I doubt that it will be, at least to this large an extent, but who knows?

So what does this portend for the future? Well, there are (as always) different possibilities. The first that comes to mind is (again taken at face value), since the supposed warming effects of increasing CO2 are still twice the size of these cloud effects, if clouds are switching from augmenting anthropogenic warming to mitigating it, then what we might be seeing is a new period of reduced heating of the global oceans, as well as a continued plateau in global surface temperatures. The timing roughly coincides with the recent switch of the Pacific Decadal Oscillation (PDO) to its negative phase. This is just one possibility, and I’m sure readers here can suggest others.

Anyway, this is all very new, and seldom in my work has the final analysis ended up as clear cut as the initial analysis suggested. I don’t know when (or if) I’ll have time to do a careful evaluation of the results and submit them for publication. But I thought I would throw these results out there for discussion anyway.

Supplementary Evidence on Cloud Feedback
Since my discussion of clouds as ‘forcing’ versus ‘feedback’ is admittedly not very convincing, here is a lag regression plot of SSM/I cloud water versus HadSST3 sea surface temperatures during July 1987 thru August 2013. What it suggests, at least for year-to-year variability, is that a decrease in clouds tends to contribute to ocean warming, then clouds increase in response to that warming, leading to surface cooling:

The Version 5.6 global average lower tropospheric temperature (LT) anomaly for September, 2013 is +0.37 deg. C (click for larger version):

The global, hemispheric, and tropical LT anomalies from the 30-year (1981-2010) average for the last 21 months are:

YR MON GLOBAL NH SH TROPICS
2012 1 -0.145 -0.088 -0.203 -0.245
2012 2 -0.140 -0.016 -0.263 -0.326
2012 3 +0.033 +0.064 +0.002 -0.238
2012 4 +0.230 +0.346 +0.114 -0.251
2012 5 +0.178 +0.338 +0.018 -0.102
2012 6 +0.244 +0.378 +0.111 -0.016
2012 7 +0.149 +0.263 +0.035 +0.146
2012 8 +0.210 +0.195 +0.225 +0.069
2012 9 +0.369 +0.376 +0.361 +0.174
2012 10 +0.367 +0.326 +0.409 +0.155
2012 11 +0.305 +0.319 +0.292 +0.209
2012 12 +0.229 +0.153 +0.305 +0.199
2013 1 +0.496 +0.512 +0.481 +0.387
2013 2 +0.203 +0.372 +0.033 +0.195
2013 3 +0.200 +0.333 +0.067 +0.243
2013 4 +0.114 +0.128 +0.101 +0.165
2013 5 +0.083 +0.180 -0.015 +0.112
2013 6 +0.295 +0.335 +0.255 +0.220
2013 7 +0.173 +0.134 +0.212 +0.074
2013 8 +0.158 +0.111 +0.206 +0.009
2013 9 +0.367 +0.342 +0.392 +0.192

The Effect of Convective Oscillations On Tropospheric Temperature
I sometimes get asked why the tropospheric temperature variations are so large on a month-to-month basis. As I have mentioned before, these are usually due to natural oscillations in convective heat transfer from the ocean surface to the atmosphere. Just how large are these variations? The global average rate of energy transfer by moist convection (precipitation systems) has been estimated to be around 100 Watts per sq. meter. Since satellite (SSM/I) measurements of global oceanic rainfall have a monthly standard deviation of 3%, this equates to ~3 W/m2 monthly variations in convective heating of the troposphere. A quick calculation using the heat capacity of air will show that 3 W/m2 of more (or less) heating will raise (or lower) the tropospheric temperature by about 0.2 deg. C (assuming no other energy exchanges are affected). This is indeed the approximate size of the month-to-month variations in tropospheric temperature that we observe.

Note: In the previous version (v5.5, still provided to NOAA due to contract with NCDC) the temps are slightly cooler, probably due to the uncorrected diurnal drift of NOAA-18. Recall that in v5.6, we include METOP-A and NOAA-19, and since June 2013 they are the only two satellites in the v5.6 dataset, whereas v5.5 does not include METOP-A and NOAA-19.

Popular monthly data files:

uahncdc_lt_5.6.txt (Lower Troposphere)
uahncdc_mt_5.6.txt (Mid-Troposphere)
uahncdc_ls_5.6.txt (Lower Stratosphere)