Russ Steele
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Israeli Astrophysicist Dr. Nir Shaviv has written and paper showing the solar connection to global warming: 'IPCC cannot ignore that the sun has a large climatic effect on climate' Here is part of the Dr. Shaviv's paper to be published in Journal of Geophysical Research.
Over the 11 or so year solar cycle, solar irradiance changes by typically 0.1%. i.e., about 1 W/m2 relative to the solar constant of 1360 W/m2. Once one averages for the whole surface of earth (i.e., divide by 4) and takes away the reflected component (i.e., times 1 minus the albedo), it comes out to be about 0.17 W/m2 variations relative to the 240 W/m2. Thus, if only solar irradiance variations are present, Earth's sensitivity has to be pretty high to explain the solar-climate correlations (see the collapsed box below).
However, if solar activity is amplified by some mechanism (such as hypersensitivity to UV, or indirectly through sensitivity to cosmic ray flux variations), then in principle, a lower climate sensitivity can explain the solar-climate links, but it would mean that a much larger heat flux is entering and leaving the system every solar cycle.
The IPCC's small solar forcing and the emperor's new clothes.
Now, is there a direct record which measures the heat flux going into the climate system? The answer is that over the 11-year solar cycle, a large fraction of the flux entering the climate system goes into the oceans. However, because of the high heat capacity of the oceans, this heat content doesn't change the ocean temperature by much. And as a consequence, the oceans can be used as a "calorimeter" to measure the solar radiative forcing. Of course, the full calculation has to include the "calorimetric efficiency" and the fact that the oceans do change their temperature a little (such that some of the heat is radiated away, thereby reducing the calorimetric efficiency).
It turns out that there are three different types of data sets from which the ocean heat content can derived. The first data is is that of direct measurements using buoys. The second is the ocean surface temperature, while the third is that of the tide gauge record which reveals the thermal expansion of the oceans. Each one of the data sets has different advantages and disadvantages.
The ocean heat content, is a direct measurement of the energy stored in the oceans. However, it requires extended 3D data, the holes in which contributed systematic errors. The sea surface temperature is only time dependent 2D data, but it requires solving for the heat diffusion into the oceans, which of course has its uncertainties (primarily the vertical turbulent diffusion coefficient). Last, because ocean basins equilibrate over relatively short periods, the tide gauge record is inherently integrative. However, it has several systematic uncertainties, for example, a non-neligible contribution from glacial meting (which on the decadal time scale is still secondary).
Nevertheless, the beautiful thing is that within the errors in the data sets (and estimate for the systematics), all three sets give consistently the same answer, that a large heat flux periodically enters and leaves the oceans with the solar cycle, and this heat flux is about 6 to 8 times larger than can be expected from changes in the solar irradiance only. This implies that an amplification mechanism necessarily exists. Interestingly, the size is consistent with what would be expected from the observed low altitude cloud cover variations.
However, if solar activity is amplified by some mechanism (such as hypersensitivity to UV, or indirectly through sensitivity to cosmic ray flux variations), then in principle, a lower climate sensitivity can explain the solar-climate links, but it would mean that a much larger heat flux is entering and leaving the system every solar cycle.
The IPCC's small solar forcing and the emperor's new clothes.
Now, is there a direct record which measures the heat flux going into the climate system? The answer is that over the 11-year solar cycle, a large fraction of the flux entering the climate system goes into the oceans. However, because of the high heat capacity of the oceans, this heat content doesn't change the ocean temperature by much. And as a consequence, the oceans can be used as a "calorimeter" to measure the solar radiative forcing. Of course, the full calculation has to include the "calorimetric efficiency" and the fact that the oceans do change their temperature a little (such that some of the heat is radiated away, thereby reducing the calorimetric efficiency).
It turns out that there are three different types of data sets from which the ocean heat content can derived. The first data is is that of direct measurements using buoys. The second is the ocean surface temperature, while the third is that of the tide gauge record which reveals the thermal expansion of the oceans. Each one of the data sets has different advantages and disadvantages.
The ocean heat content, is a direct measurement of the energy stored in the oceans. However, it requires extended 3D data, the holes in which contributed systematic errors. The sea surface temperature is only time dependent 2D data, but it requires solving for the heat diffusion into the oceans, which of course has its uncertainties (primarily the vertical turbulent diffusion coefficient). Last, because ocean basins equilibrate over relatively short periods, the tide gauge record is inherently integrative. However, it has several systematic uncertainties, for example, a non-neligible contribution from glacial meting (which on the decadal time scale is still secondary).
Nevertheless, the beautiful thing is that within the errors in the data sets (and estimate for the systematics), all three sets give consistently the same answer, that a large heat flux periodically enters and leaves the oceans with the solar cycle, and this heat flux is about 6 to 8 times larger than can be expected from changes in the solar irradiance only. This implies that an amplification mechanism necessarily exists. Interestingly, the size is consistent with what would be expected from the observed low altitude cloud cover variations.
I noted the ocean cooling and reduction in sea level rise here.
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