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.. By far the most important greenhouse gas is water vapor because of its abundance and its extensive IR absorption features ..
The question is odd. It's a bit like saying "I have put another blanket on the bed, and now it's warmer. Did the blanket cause the rise in temperature?"The answer is obviously yes- the questions are how much and did anything else also have an effect?
.. In general, I agree with most of what's there. The main difference remains in their continued misconception about the atmosphere being able to emit black body radiation (the grey atmosphere model is wrong, what Judith Curry has called "kindergarten science"). It can't.What the CO2 and other greenhouse gases do is absorb IR emitted BY THE WARM SOLID OR LIQUID SURFACE OF THE EARTH, and transfer by inelastic collision energy to N2 and O2 and Ar, gases, which CANNOT re-emit IR energy to outer space. At steady state, the IR that DOES manage to escape to outer space through the windows where there is no appreciable absorption by greenhouse gases must balance the net incoming Solar radiation which is mainly in the visible and near-IR. I was glad to see that the book quotes analbedo of 0.28, which happens to be what I calculated after correction for truncation error (the IPCC numbers give an albedo of 0.24, a little on the low side). The wrong idea that the atmosphere actually absorbs AND THEN RE-EMITS black body radiation (according to the Stefan-Boltzmann T^4 relation) I think results in their wrong factor of 1/2 in the temperature sensitivityrelation. Compare my simple, compact and true derivation of temperature sensitivity by simply differentiating the Stefan-Boltzmann law WHICH APPLIES TO A SOLID OR LIQUID EMITTING SURFACE, NOT THE ATMOSPHERE WHICH IS A GAS which cannot emit a continuous, i.e. black body, spectrum. Because of a cancellation of errors the book actually got close to predicting the observed 0.7 degree (they call it 0.6 degree) rise in global temperature since about 1850. They got 0.8 degrees. Multiply this by a factor of 2 to correct for their mistake in using f/2 instead of f in the temperature sensitivity formula, and you get 1.6 degrees, which means they are a factor of 2 too high (my contention)
Nice theory JimBob!Unfortunately, the Earth's magnetosphere only deflects slow moving ionized particles in the solar wind. This protects our atmosphere and prevents the solar wind from ripping it away from the Earth.
I started a separate topic to discuss a bit more the effect on magnetic field weakening/pole reversal and climate change: http://www.thenakedscientists.com/forum/index.php?topic=39128.0;topicseen
Quote from: JP on 06/05/2011 23:30:22I started a separate topic to discuss a bit more the effect on magnetic field weakening/pole reversal and climate change: http://www.thenakedscientists.com/forum/index.php?topic=39128.0;topicseenYou may want to rethink the wording of the question. For example - field strength change vs climate change
Quote from: Geezer on 06/05/2011 01:20:40Nice theory JimBob!Unfortunately, the Earth's magnetosphere only deflects slow moving ionized particles in the solar wind. This protects our atmosphere and prevents the solar wind from ripping it away from the Earth.That was precisely the point of bringing in the fact that Mars has no atmosphere. Without an atmosphere, the whole problem would not exist - and neither would we. Sun cycles greatly affect the atmosphere of earth; cycles as short as 11 yaers or so.Induced field. Venus - http://en.wikipedia.org/wiki/Venus%27_atmosphere - Paragraph 3I also said above " The Earth's magnetic field is like a quasi-potentiometer moderating, only in part, the amount sun's energy that is put into the earth's climatic system. "