Stalking the Rogue Hotspot

[I’m making this excellent essay a top sticky post for a day or two, I urge sharing it far and wide. New stories will appear below this one.  – Anthony]

Guest Post by Willis Eschenbach

Dr. Kevin Trenberth is a mainstream climate scientist, best known for inadvertently telling the world the truth about the parlous state of climate science itself. In the Climategate emails published in 2009, it was revealed that in private he had said:

The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.

This from a spokesman for the folks who have been telling us for years that the science is settled …  

However, the problem seems to be solved. Kevin Trenberth, Distinguished Senior Scientist, (as he is described on his web page) has emailed Joe Romm, Distinguished Senior Climate Alarmist, about the status of Dr. Trenberth’s tireless quest to find the missing heat, stating (emphasis in Romm’s post):

“We can confidently say that the risk of drought and heat waves has gone up and the odds of a hot spot somewhere on the planet have increased but the hotspot moves around and the location is not very predictable. This year perhaps it is East Asia: China, or earlier Siberia? It has been much wetter and cooler in the US (except for SW), whereas last year the hot spot was the US. Earlier this year it was Australia (Tasmania etc) in January (southern summer). We can name spots for all summers going back quite a few years: Australia in 2009, the Russian heat wave in 2010, Texas in 2011, etc.”

I’ll return to the serious question of Dr. Trenberth’s missing heat in a moment. But first, let’s consider Dr. Trenberth’ statement, starting with the section highlighted in bold in Joe’s post, viz:

“We can confidently say that the risk of drought and heat waves has gone up and the odds of a hot spot somewhere on the planet have increased but the hotspot moves around and the location is not very predictable.”

That single sentence contains all the required elements of a good novel—unpredictability, increasing risks, a dangerous moving “hotspot”, confident experts, a planet in peril … all the stuff that goes into an exciting story, it’s perfect for a direct-to-DVD movie.

The only problem with Dr. Trenberth’s statement is that like all novels, it’s fiction. To start with, Dr. Trenberth is very careful not to claim that droughts and heat waves and “hotspots” have actually increased. Did you notice that? You need to watch statements about climate very closely. He didn’t say that the number of droughts or heat waves have gone up. That’s a falsifiable statement, and one which is decidedly not true, so he prudently avoided that pitfall. The IPCC itself has said that we have no evidence of any increases in drought, in heat waves, or in any other climate extremes, despite a couple of centuries involving a couple of degrees of warming. But then, Dr. Trenberth didn’t say droughts or heat waves have gone up, did he?

He said the risk of droughts and heat waves has gone up. He said the “odds of a hot spot somewhere on the planet” have gone up. Presumably, this deep knowledge of the probability of future climate catastrophes has been vouchsafed to Dr. Trenberth by means of the climate models … the same climate models that are part of the “travesty” because they can’t account for the missing heat. He’s citing risks and odds based on climate models that were unable to forecast the current hiatus in warming which has gone on for fifteen years or so now, despite continuing increases in CO2 and methane and black carbon and the like …

The part that I particularly enjoyed is the foreboding, menacing quality of his claim that there is now some roving “hotspot”, whose location “moves around” and “is not very predictable”. Dang, what if the dreaded “hotspot” comes to my town? Does he mean we might be faced with the much-feared phenomenon known locally as “a really hot summer”. We know those summers, when  bad things happen, like the time when Jimmy Fugate punched out the eleventh guy, by Jimmy’s actual count, who had said “Hot enough for ya?” to him on that fateful August day … but although I digress, we know the danger is real, because as Dr. Trenberth warns us, the hot spot is on the move, viz:

It has been much wetter and cooler in the US (except for SW), whereas last year the hot spot was the US. Earlier this year it was Australia (Tasmania etc) in January (southern summer). We can name [hot]spots for all summers going back quite a few years …

I gotta admit, this is stunning news. Dr. Trenberth is giving us inside climate information, full of extra scientificity, that every summer some places are extra-hot, while you’d be amazed to find out, other locations have extra-cool summers. We’re in one of the latter where I live. Around here, this has been one of the coolest summers in recent years.

So following in Dr. Trenberth’s trail-blazing footsteps, here’s my new climate theory. It revolves around the dreaded “coldspot”. You may be shocked when I tell you that every summer there’s a “coldspot” somewhere in the world, a place where the summer is much colder than usual. Last year the coldspot was Russia. This year it has moved to Northern California where I live. Here’s what makes coldspots so dangerous, as highlighted by Dr. Trenberth. The coldspot “moves around and the location is not very predictable” … so you should be very afraid, because science.

I mean … are we supposed to take this talk of “moving hotspots” seriously? Is this how desperate the alarmists are  getting?

Joe Romm’s quote of Dr. Trenberth closes with this suitably ominous line, which I assume is preparing us for the sequel …

Similarly with risk of high rains and floods: They are occurring but the location moves.

Ahhh, Dr. Trenberth is referring to the dreaded “wetspot”, and he doesn’t mean the one the baby leaves on your shoulder. Did you know that every year during the rainy season there’s a “wetspot” somewhere in the world, a place where it rains more than usual? And did you know the wetspot moves around the world and the location is not very predictable? There’s no end to the insights available in Dr. Trenberth’s concepts …

I have to say, I find Dr. Trenberth’s claims both very depressing and very encouraging. They’re depressing because they are a million miles from science. It’s just a frightening tale for children around the campfire, about how the risks of bad things are rising, and it’s worse than we thought.

But it’s encouraging, because when the intellectual leaders of the climate alarmism movement sink to peddling those kinds of scare stories, it’s a clear indication that they’re way short of actual scientific arguments to back up their inchoate fears of Thermageddon.

In any case, let me move on to the more serious topic I mentioned above, regarding Dr. Trenberth’s infamous “missing heat”. Let me suggest where some of it is going. It’s going back out to space.

One of the main thermal controls on the planet’s heat balance is the relationship between surface temperature on one hand, and the time of day of cumulus and cumulonimbus formation in the tropics. On days when the surface is warmer, clouds form earlier in the day. The opposite is true when the surface is cooler, clouds form later. This control operates on an hourly basis. I’ve shown how this affects the daily evolution of tropical temperature here and here using the TAO moored buoy data. Here’s a bit of what I demonstrated in those posts. Figure 2, from the second citation, shows how cold mornings and warm mornings affect the evolution of the temperature of the ensuing day.

Figure 2. Average of all TAO buoy records (heavy black line), as well as averages of the same data divided into days when dawn is warmer than average (heavy red line), and days when dawn is cooler than average (heavy blue line) for each buoy. Light straight lines show the difference between the previous and the following 1:00 AM temperatures.

The control of the surface temperature is exerted in two main ways: 1) in the morning, cumulus cloud formation reduces incoming solar radiation by reflecting it back to space, and 2) in the afternoon, thunderstorms both increase cloud coverage and remove energy from the surface and transport it to the upper troposphere. We can see both of these going on in the average temperatures above.

The black line in Figure 2 shows the average day’s cycle. The onset of cumulus is complete by about 10:00. The afternoon is warmer than the morning. As you would expect with an average, the 1 AM temperatures are equal (thin black line).

The days when the dawn is warmer than average for each buoy (red line) show a different pattern. There is less cooling from 1AM to dawn. Cumulus development is stronger when it occurs, driving the temperature down further than on average. In addition, afternoon thunderstorms not only keep the afternoon temperatures down, they also drive evening and night cooling. As a result, when the day is warmer at dawn, the following morning is cooler.

In general, the reverse occurs on the cooler days (blue line). Cooling from 1 AM until dawn is strong. Warming is equally strong. Morning cumulus formation is weak, as is the afternoon thunderstorm foundation. As a result, when the dawn is cooler, temperatures continue to climb during the day, and the following 1AM is warmer than the preceding 1 AM.

Regarding the reduction in incoming solar energy, in a succeeding post called “Cloud Radiation Forcing in the TAO Dataset“, I provided measurements of the difference between the shortwave and longwave radiation effects of tropical clouds, based on the same TAO buoy data. The measurements showed that around noon, when cumulus usually form, the net effect of cloud cover (longwave minus shortwave) was a reduction of half a kilowatt per square metre in net downwelling radiative energy.

In addition to that reduction in downwelling radiation, there is another longer-term effect. This is that we lose not only the direct energy of the solar radiation, but also the subsequent “greenhouse radiation” resulting from the solar radiation. In the TAO buoy dataset, the 24/7 average downwelling solar radiation reaching the surface is about 250 W/m2. Via the poorly-named “greenhouse effect” this results in a 24/7 average downwelling longwave radiation of about 420 w/m2. So for every ten W/m2 of solar we lose through reflection to space, we also lose an additional seventeen W/m2 of the resulting longwave radiation.

This means that if the tropical clouds form one hour earlier or later on average, that reduces or increases net downwelling radiation by about 50 W/m2 on a 24/7 basis. This 100 W/m2 swing in incoming energy, based solely on a ± one-hour variation in tropical cloud onset time, exercises a very strong daily control on the total amount of energy entering the planetary system. This is because most of the sun’s energy enters the climate system in the tropics. As one example, if the tropical clouds form on average at five minutes before eleven AM instead of right at eleven AM, that is a swing of 4 W/m2 on a 24/7 basis, enough to offset the tropical effects of a doubling of CO2 …

Not only that, but the control system is virtually invisible, in that there are few long-term minute-by-minute records of daily cloud onset times. Who would notice a change of half an hour in the average time of cumulus formation? It is only the advent of modern nearly constant recording of variables like downwelling long and shortwave radiation that has let me demonstrate the effect of the cloud onset on tropical temperatures using the TAO buoy dataset.

While writing this here on a cold and foggy night, I realized that I had the data to add greatly to my understanding of this question. Remember that I have made a curious claim. This is that in the tropics, as the day gets warmer, the albedo increases. This means that we should find the same thing on a monthly basis—warmer months should result in a greater albedo, there should be a positive correlation between temperature and albedo. This is in contrast to our usual concept of albedo. We usually think of causation going the other way, of increasing albedo causing a decrease in temperature. This is the basis of the feedback from reduced snow and ice. The warmer it gets, the less the snow and ice albedo. This is a negative correlation between albedo and temperature, albedo going down with increasing temperature. So my theory was that unlike at the poles, in the tropics the albedo should be positively correlated with the temperature. However, I’d never thought of a way to actually demonstrate the strength of that relationship at a global level.

So I took a break from writing to look at the correlation of surface temperature and albedo in the CERES satellite dataset. Here’s that result, hot off of the presses this very evening, science at its most raw:

Figure 3. Correlation between albedo and temperature, as shown by the CERES dataset. Underlying data sources and discussion are here.

Gotta confess, I do love results like that. That is a complete confirmation of my claim that in the tropics, as the temperature increases, the albedo increases. Lots of interesting detail there as well … fascinating.

My conclusion is that Dr. Trenberth’s infamous “missing heat” is missing because it never entered the system. It was reflected away by a slight increase in the average albedo, likely caused by a slight change in the cloud onset time or thickness.

My regards to everyone,

w.