Thursday, February 19, 2015

The Greenhouse Effect

The greenhouse effect has been known for 190 years.
The existence of the greenhouse effect was argued for by Joseph Fourier in 1824. The argument and the evidence was further strengthened by Claude Pouillet in 1827 and 1838, and reasoned from experimental observations by John Tyndall in 1859, and more fully quantified by Svante Arrhenius in 1896.  In 1917 Alexander Graham Bell wrote “[The unchecked burning of fossil fuels] would have a sort of greenhouse effect”, and “The net result is the greenhouse becomes a sort of hot-house.”[ Bell went on to also advocate for the use of alternate energy sources, such as solar energy.
An important issue though is what the sensitivity of global temperatures is to the concentration of carbon dioxide in the atmosphere, that is, what temperature can we expect given a certain amount of atmospheric CO2.  A study has just been published that provides some evidence.  In non-technical terms
[I]t comes, of all places, from a set of tiny microorganisms, preserved in ocean sediments, whose shells hold chemical fingerprints of past carbon dioxide concentrations going back millions of years. An analysis of these carbon dioxide fingerprints, in conjunction with other climate records stretching back millions of years, shows that Earth’s sensitivity to carbon dioxide has long fallen in that familiar 1.5 to 4.5 degrees [Celsius] range.
First of all, it is evidence supporting the claims of climate scientists for global warming.  But, recalling that this can mean up to 8 degrees Fahrenheit increase in global temperatures it still suggests a baked planet.  And since these temperatures are not uniformly distributed it can mean much larger increases in some parts of the world.

It appears that there'll be winter monsoons in the Northeast, mega-droughts in the Midwest and Southwest, but the Pacific Northwest will be mainly ok except for a loss of sealife to ocean acidification and as long as they can collect sufficient water without a winter snowpack.