The October issue of Geology had two papers and a commentary on the extent of the East Antarctic Ice Sheet in the mid-Pliocene (roughly 3 million years ago). Both papers are pretty esoteric and I won't go into details of the work or the conclusions, but you can find the abstracts here and here. The implications of these two papers are analyzed in a commentary that can be found here.
Why, you may ask, is this worth the attention of anyone outside of a handful of paleoclimatologists? Simple. One of the great boogie men of the Church of Global warming is that the sea level will rise, there will be massive inundation of coastal areas, millions will die, mass hysteria will reign, dogs and cats will be living together...in other words, total chaos. Current Church dogma would put the sea level rise due to global warming at 40 meters (about 150 feet) above current levels. This number assumes the complete disappearance of the Greenland Ice Sheet (which would raise the sea level about 25 feet), the disappearance of the West Antarctic Ice Sheet (adding another 18 feet), and the rest contributed by the melting of the East Antarctic Ice Sheet (EAIS), which by itself contains the equivalent of 175 feet of sea level rise, but even the most rapid climate change dogmatist is not predicting the total disappearance of the EAIS.
It turns out that the last time atmospheric carbon dioxide levels were as high as they are now was in what is know as the mid-Pliocene warm period (3.3 to 3 million years ago). That being the case, it is a fair question to ask what the sea level was and what was the extent of the EAIS back then, which is what drove the work behind the two papers cited above. Greg Balco, the author of the commentary, sums up the conclusions of the two papers (and earlier work) saying, "In 2009, it appeared that significant EAIS deglaciation must have happened even though it couldn't have. Now, subsequent research seems to show that although it could have happened, it is not at all clear that it did."
This last is a long, long way from saying the the science is "settled" and, given that all of the authors involved are Americans, one senses a bit of equivocation in their conclusions as they must all have future funding from NASA, NOAA, and NSF in mind and want to avoid being branded as "wrong thinkers".
Earth is warming as it has many times in the past. Fossil fuel combustion may or may not be contributing to this warming. The carbon cycle and the Earth's climate are both very complex systems that no one understands. Where all this ends up is anyone's guess, but that is all it is...a guess. Nothing is "settled".
No comments:
Post a Comment