Guest Post by Willis Eschenbach
Well, after my brief digression to some other topics, I’ve finally been able to get back to the reason that I got the CERES albedo and radiation data in the first place. This was to look at the relationship between the top of atmosphere (TOA) radiation imbalance and the surface temperature. Recall that the IPCC says that a change in the TOA radiation of 3.7 W/m2 from a doubling of CO2 will lead to a 3°C ± 1.5°C temperature increase. This 3°C per doubling is called the “climate sensitivity”, and its value is an open question.
Figure 1, on the other hand, shows my results regarding the same question of the climate sensitivity. These reveal nothing like a 3°C temperature rise from a doubling of CO2:
Figure 1. Gridcell-by-gridcell linear trends of the change in surface temperature (∆T) given the change in TOA radiation (∆F). Note that the surface temperature data is gridded on a 5°x5° gridcell, while the CERES TOA radiation data is on a 1°x1° gridcell basis. Graph includes a two-month lag between change in forcing and the change in temperature.
There are a variety of interesting aspects to this particular graph. Let me start by describing how I constructed it.
I began by taking the gridded HadCRUT3 temperature data for the period of the CERES study, Jan 2001 to Oct 2005. The HadCRUT data is on a 5°x5° gridcell, so I first expanded that to 1°x1° gridcells. Then I took the first differences (∆T) by subtracting each month from the succeeding month, to get the monthly change in temperature (∆T) in each gridcell.
Then I compared that ∆T dataset to the change in TOA radiation (∆F), which was constructed from the CERES TOA data. For each gridcell, I took the linear trend of the temperature changes ∆T with respect to ∆F.
Of course, the climate sensitivity results from this procedure are in units of temperature change per forcing change, which is °C per watt/square metre. To convert it to change in temperature per doubling of CO2, I multiplied the results by 3.7 W/m2 per doubling of CO2.
Finally, I needed to adjust for the lag in the system. I did this in two ways. First, I selected the lag which gave the largest temperature change, which was a two month lag. These are the results shown in Figure 1. However, this is a cyclical record of the annual fluctuations, so the equilibrium sensitivity will be underestimated. Per the insights gained from my last analysis, “Time Lags in the Climate System“, the time lag is related to the size of the reduction in temperature swing. A 1-2 month lag in the system indicates a reduction in fluctuation of about 50%. So for my final adjustment, I doubled the indicated climate sensitivity. The results of this are the values shown in Figure 1.
Now, I have long argued, solely from first principles, that climate sensitivity is a non-linear function of temperature. I have said that the sensitivity was greater when it is colder, and that it is smaller when it is warmer. I have held that this relationship was non-linear, with a kink at the temperature range for tropical thunderstorm formation. Finally, I have also argued that in some places in the tropics the climate sensitivity is actually negative, due to the action of tropical clouds and thunderstorms.
To test these claims, I plotted the sensitivity for each gridcell shown in Figure 1 against the annual average temperature for that same gridcell. The results are shown in Figure 2. As far as I know, this is the first observational evidence that shows the actual relationship between climate sensitivity and temperature, and it supports all of my contentions about that relationship.
Figure 2. Scatterplot of gridcell climate sensitivity versus gridcell temperature. Colors indicate the latitude, with red at the tropics, yellow in the temperate zones, and blue at the poles. Gray dashed line shows the linear trend, indicating that the climate sensitivity varies generally as -0.009 * temperature + 0.32 (p-value < 1e-16).
There are some important things about this plot. First, it strongly supports my claim that the climate sensitivity varies inversely with the temperature. Next, it shows that a number of areas of the tropics actually do have negative climate sensitivity. Finally, it shows that the relationship is non-linear with a kink at around the temperature for the formation of tropical thunderstorms. This is important corroborative evidence for my hypothesis that the tropical clouds and thunderstorms act as governors of the tropical temperature and are the source of the negative climate sensitivity.
Let me close by railing a bit against the pernicious nature of averages. Consider Figure 2. Normally, far too many climate scientists would take an average of that data, and come up with some number as the average climate sensitivity. But that number is meaningless, and worse, it gives the impression that the sensitivity is a fixed number. It is nothing of the sort. Not only is it not fixed, it is far, far from linear, and it goes negative at times. It is a dynamic response to changing conditions, not some fixed value.
As a result, when we average it, we come away with entirely the wrong impression of what is happening in that most complex of phenomena, the climate system. While averaging is often useful, it conceals as much as it reveals, and it can lead one to badly erroneous conclusions. That is why so many of my graphs and charts show thousands of individual points, as in Figure 2. Only by seeing the whole picture can we hope to understand the system.
My best to all,
w.
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RE: the equatorial cooling. There we have it, nature’s “tower heatsinks” – CuNim – shooting all the heat out into space. Probably also an element of electromagnetic energy flux via all the sprites, etc. In any case a negative energy balance in such locales.
Another thought, has anyone ever tried to demonstrate an increase in Hadley Cell velocity? That would also be supportive of this result, with the increased equatorial divergence, and increased subsidence in the mid latitudes (creating the slightly positive numbers up there).
I would be keenly interested to see the results broken down by land vs. ocean.
I wonder if we’ll ever see Mr. Eschenbach embrace the idea that 390PPM of CO2 does nothing measurable to the Earth’s surface temperature. Surely that is a conclusion that can be drawn from the data. Sun heats Earth and water. Water and Earth heat air. Radiation is a dissipative process that always acts in the same direction as conduction and convection–it is not a mechanism for conveying work-energy from load to source. It always conveys work-energy from source to load.
It is said that GHEs delay energy’s escape to space. Is it perpetually mobile? If not, what is the median value and distribution of this delay? How long must this delay be in order to contribute positive diurnal feedback?
Well done Willis. 🙂
It is always refreshing to see an ‘outsider’ enter a field and provide insights through simple analysis rather than paper after paper based on more and more complex formalisms.
While this will be peer-reviewed here, it deserves to be published in a journal, but I foresee a battle as the entrenched experts fail to come to grips with its simple concepts.
Willis, you keep rattling the cage with that hammer of yours.
This is going to be an interesting thread.
Figure 2 scatterplot appears to me to be an inverted “U”, of say 2nd or 3rd order. Peak sensitivity is <0.5°C/3.7W/M^2 which is still, at worst, miniscule.
Yet another of a myriad of nails in the cAGW coffin.
Keep 'em coming Willis!!
J Storrs Hall says:
June 19, 2012 at 10:35 am
So would I, J, so would I … but all these things take time. In the meantime, you can see the difference when you look at Figure 1.
w.
bacullen says:
June 19, 2012 at 10:47 am
Possible, bacullen, but the problem is that we lack data near the poles. I have only calculated the trend in gridcells with a minimum of 36 data points (out of a possible 58 months of data), so a number of the cells near both poles haven’t been calculated.
w.
@ur momisugly Willis “In the meantime, you can see the difference when you look at Figure 1.”
First of all, thank you! Not only for this particular post, but for all the other thought provoking ideas you have posted. Regarding the differences between land and sea, yes, the first and obvious difference is that the wettest areas, really do show how well water vapor works to transport any extra energy input into the system. As Chiefio says, the atmosphere is a sort of spherical heat pipe using water vapor as the working fluid. And that leads to a little puzzle for me; here we have a nice demonstration of heat transport via water vapor, and then I notice the little green patches down in Antarctica. Who ordered that? One of the dryest places in the world, and we have a negative sensitivity there? Makes me wonder whether the data on radiation is a little wonky, or perhaps the temperature records have been fiddled.
Wow!
That all makes perfect sense, so clearly it will never be considered for inclusion in the IPCC’s next report. Undoubtedly, it will be trashed by ‘climate scientists’ for using raw data, not fitting their models, not being pal reviewed and/or representing a dire threat to their comfortable grant income.
Willis, I think you need to use a change in TOA radiation of around 15W/m2, not 3.7, to get the IPCC answer. I cannot think of any reason why you should do that, but perhaps some nice ‘clmiate scientist’ could help find one.
Willis, I stand in awe!!!
Warmists, take your best shots!
Another heatwave rolling the the US.
Another major solar flare eruption hits the Earth a few days ago.
http://news.yahoo.com/solar-flares-fire-double-sun-storm-earth-120149575.html
Coincidence?????
Does all that extra energy in the upper atmosphere contribute to higher surface temps???
It looks to me that a non-linear interpertation could be a better fix. Maybe positive 0.4 at 0 degree C, zero at +-25 degree C, and negative below -25 or above +25. More data at the extrems would be very interesting
Question: If the TOA radiates more energy out to space for any reason, say the effect of CO2 doubling, then wouldn’t that cool the atmosphere more, all the way down to the surface, until the TOA radiation balanced the TOA insolation?
Publish it! Until you do that, it can’t get it into the IPCC assessment to balance everything else. While it stays in a blog its only use is to reinforce those already convinced.
Excellent work, Willis, congratulations. Still, there could be some extra justifications and comments added for the research to become fairly publishable. But I would bet it may be correct.
Not sure if you accounted for this, but a 1°x1° cell on the surface of the Earth is not the same square meters as the same cell at TOA. The radiating surface for TOA and Earth’s Surface are not the same. In addition, the Earth’s surface is blocked in most areas by clouds, etc.
Of course, the calculations are only good for the time period that the values in the gridcells remain the same. Nice post.
Not sure my comment made it in. Did you account for the fact the surface area of a 1×1 grid on the Earth’s surface is not the same as at TOA?
It makes sense that the climate sensitivity be non-linear, and that it decreases as T goes up – negative feedback in other words. I don’t know why certain people continue to search for a single number.
Your average comment reminds me of the economist joke where a guy has his head in the oven and his feet in the freezer. On average, the guy’s temperature is right on!
I always learn something from you, Willis. Thank you for your tireless efforts!
fredb says:
June 19, 2012 at 11:19 am
Thanks for the vote, fredb. While I do publish in the journals, I am much more interested in affecting the ongoing scientific dialog about the climate. For that purpose, publishing here has much more effect than publishing in the journals.
Rest assured that scientists on both sides of the climate debate read WUWT. The skeptics read it to find out the latest scientific advances and find evidence for their theories, while the AGW supporters read it to find out what the lunatics like me are up to. Reading WUWT (and Climate Audit) are requirements if you are serious about climate science and you want to stay up-to-date. So I reach many, many more scientists of all kinds here than I could ever hope to reach in any but the highest-impact journals.
In addition, I also reach a host of people who for various reasons don’t read the scientific journals. Often these folks are policymakers or decision makers of various kinds, most are voters, and all of them are part of the larger scientific community. Since the climate question is not only scientific but involves policy at all levels, I see this greater outreach as being as important as reaching the scientists.
This is not to diss the value of publishing in the journals, and I do so when I can. Unfortunately, every hour that I spend dealing with the journals, or translating a post like the one above into that most dense and opaque language called “scientese”, is an hour when I can’t be doing the research and investigations that are the raw meat that feeds my scientific hunger …
Next is the question of timing. It often takes months to get a piece published. As I said above, I’m interested in affecting the ongoing discussion of the issues of climate science, not rehashing yesterday’s news. To do that, I need to be timely and topical. I need to be able to discuss the issues while they are still fresh.
Next, publishing here means that I get invaluable assistance in understanding the results that I present. I’m a lone wolf, I work as a carpenter, I don’t have a bunch of colleagues with whom to toss these ideas around. As a result, the realtime feedback and the pointing out of my errors and successes here on the web is of utmost importance to me.
Finally, a) we’re either too near to or past the deadline for inclusion in the fifth IPCC report, and b) the odds that the IPCC would include such heretical thoughts as mine are minuscule …
However, all is not lost. I’m considering putting out a call for co-authors to take some of my ideas and rewrite them and get them published … but as always, time is the issue.
w.
Impressive work of a citizen scientist.
Willis, can’t we have these contributions put together and delivered as ebook?
Amazon makes that easy. It would be easier to read, reach many more people and even pay for all your effort.