I’ve held for a long time that there is a regulatory mechanism in the tropics that keeps the earth’s temperature within very narrow bounds on average (e.g. ± 0.3°C over the 20th Century). This mechanism is the timing and amount of the daily emergence of the cumulus cloud field, and the timing and emergence of thunderstorms.
Now, the current paradigm is that the sun rules the temperature, and our daily experience seems to bear that out. When the amount of sun reaching the surface goes up, the temperature goes up. This has led to the claim that the temperature must perforce follow the forcing in a linear fashion. For those interested in the math, the claim is that changes in temperature are equal to changes in forcing times a constant called the “climate sensitivity”. And much energy has been wasted trying to determine the value of that constant.
Despite hundreds of thousands of hours of both human and computer time dedicated to the quest, here’s the great progress that has been made:
Figure 1. Dr. Nir Shaviv’s comments on the history of estimates of the “climate sensitivity” parameter.
I hold that this stunning lack of progress is undeniable evidence that the underlying paradigm is flawed. As I said above, daily experience shows that the sun rules the temperature … but it turns out that while this is true on land, at sea things are quite different.
To show the difference, I looked at the correlation between sunlight striking the surface, and the temperature. Remember that a positive correlation means that the temperature and the sun are moving in the same direction, as the current paradigm insists. A negative correlation, on the other hand, means that they are going in opposite directions. Here’s a map of the globe showing the correlation between temperature and solar radiation at the surface.
Figure 2. Correlation between the solar radiation at the surface, and the surface temperature. This is calculated on a 1° x 1° gridcell basis.
There are several interesting things about this graph. First, it is easy to see why people have been fooled into thinking that the temperature slavishly follows the forcing. On the land, particularly in the Northern Hemisphere, the positive correlation is nearly perfect—when the surface sun increases, the temperature goes up, and vice versa. It leads to the obvious but incorrect conclusion that it is a feature of the whole planet.
But in the tropical ocean, things are quite different. There, we find large areas of negative correlation, where when the sun is increasing the temperature is decreasing, and vice versa.
We have two choices in assigning causation in these areas. Either increasing tropical sunshine at the surface is driving the surface temperature down, which seems highly unlikely. Or, as I said above, increasing tropical temperature leads to increasing clouds, which reduces the amount of sunshine at the surface.
I’m gonna go with Choice B …
There is another interesting aspect of this graphic. We know that the reason that the Earth’s surface temperature is well above that predicted by the Stefan-Boltzmann equation is the poorly-named “greenhouse effect”. How can that be, if the temperature doesn’t follow the forcing as the climate paradigm states?
The answer is that other than in small isolated patches, this phenomenon doesn’t occur where the temperature is less than about 24°C. Below that, as the forcing goes up the temperature goes up as daily experience leads us to expect. So the greenhouse effect is able to warm up the planet … but only to a certain point. Beyond that, things start going the other direction.
Next, it is important to note the size of the phenomenon. A negative correlation between temperature and sunshine occurs over an area where no less than 17% of the sunlight is striking the earth. This is more than enough to serve as a thermoregulatory mechanism.
Finally, it is important to remember that this is not a static phenomenon. As temperatures increase and decrease these areas, the sun is moving in the opposite direction. This keeps the tropical temperature, and thus the global temperature, from getting either too hot or too cold.
My best regards to all. I’m still in the Solomon Islands, you’re welcome to read about my misadventures on my blog.
My Usual Request: When you are commenting please QUOTE THE EXACT WORDS YOU ARE DISCUSSING so we can all understand just what you are talking about.
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