Mar
Is the effect of Carbon Dioxide on temperature logarithmic?
Warmers talk incessantly, and catastrophically, about the need to reduce greenhouse gases. If the greenhouse gases in the atmosphere rise, so does the temperature, and soon enough we will all die, they say. But what would happen if the reverse were to occur? What if we were too successful at reducing greenhouse gases? Can we actually calculate the correct amount by which to reduce, and what would happen to temperatures? Would a 1% reduction in CO2, for example, reduce temperatures by 1%.
No. Too much of a reduction could actually be quite — to use their the warmers second favorite word (the first is “settled”) — catastrophic.
David Archibald, writing for Watts Up With That today, tells us that the relationship isn’t linear, it’s logarithmic:
The greenhouse gasses keep the Earth 30° C warmer than it would otherwise be without them in the atmosphere, so instead of the average surface temperature being -15° C, it is 15° C. Carbon dioxide contributes 10% of the effect so that is 3° C. The pre-industrial level of carbon dioxide in the atmosphere was 280 ppm. So roughly, if the heating effect was a linear relationship, each 100 ppm contributes 1° C. With the atmospheric concentration rising by 2 ppm annually, it would go up by 100 ppm every 50 years and we would all fry as per the IPCC predictions.
But the relationship isn’t linear, it is logarithmic. In 2006, Willis Eschenbach posted this graph [charts at WUWT] on Climate Audit showing the logarithmic heating effect of carbon dioxide relative to atmospheric concentration. I recast Willis’ first graph as a bar chart to make the concept easier to understand to the layman:
Lo and behold, the first 20 ppm accounts for over half of the heating effect to the pre-industrial level of 280 ppm, by which time carbon dioxide is tuckered out as a greenhouse gas. One thing to bear in mind is that the atmospheric concentration of CO2 got down to 180 ppm during the glacial periods of the ice age the Earth is currently in (the Holocene is an interglacial in the ice age that started three million years ago).
Plant growth shuts down at 150 ppm, so the Earth was within 30 ppm of disaster. Terrestrial life came close to being wiped out by a lack of CO2 in the atmosphere.
There is much more to this article, so head over to WWUT and read it all. I perused the comments and see that not all readers seem so sure that this theory holds water. What’s your opinion?
The quantity of CO2 in the atmospehere is dependant on the rate of evaporation of the oceans. We cannot control it.
“Thus, the observed global warming on the Earth is not caused by human-induced greenhouse gases emission, but mostly by unusually high intensity of the solar radiation during the whole passed century. The coming decrease of global temperature will take place even if the anthropogenic CO2 emission will reach record high levels in the future.
The interesting fact is that in XX century global warming took place on Mars as well as on the Earth. This global warming has been caused by considerable and prolonged increase in TSI in XX century. NASA researches were keeping a track of changes on the surface of our neighbour planet — Mars over the period from 1999 to 2005 and they have discovered a gradual melting of ice on its south pole during three Martian years and a simultaneous global warming on Mars, without, of course any participation of Martians and greenhouse effect caused by them. The same simultaneous global warming as on Mars and on the Earth have also been observed on the Jupiter, Triton (a satellite of Neptune), Pluto and several other planets of the solar system. These warmings can only be consequence of the same and only factor ― a prolonged and unusually high value of the TSI during almost whole XX century. The simultaneous global warmings on the Earth, Mars and in virtually whole solar system are the phenomena of the natural solar origin and are caused by natural ― astronomic reasons and not by industrial activity of the humans. “
http://www.gao.spb.ru/english/astrometr/index1_eng.html