Climate Change

I feel like it's time to really start getting worried about global warming. Here are a few of the recent items that concern me. Recent sampling of ice cores from Antarctica indicate that our atmospheric CO2 concentration is 27% higher than it has been at any time in the last 650,000 years [1]. No wonder it is so hard for climate modellers to predict what is going to happen. An article in Nature this week concluded that the Atlantic "thermohaline circulation" which draws warm water up from the equator and keeps Europe and possibly much of the northern hemisphere warm, has slowed 30% since 1992 [2]. Slowing of the thermohaline circulation is expected as a result of freshening of the north Atlantic from melting of multi-year arctic sea ice and arctic and antarctic ice shelfs, but there is still considerable debate over the reliability of the findings and whether it indicates a trend or a spike. It is a very difficult measurement to make, it is in conflict with some other measurements, and it's much faster than has been predicted. It's understandable however that such a measurement should cause concern, since disruption of the thermohaline circulation could happen abruptly, and could cause an rapid conversion to ice age. The freshening of the north Atlantic over the past couple decades has been well measured, and some potential implications are discussed here [3]. This page also has some cool animations of ocean circulations. Yeah, I already knew that the atmosphere has been warming and increasing in CO2 concentation at an accelerating rate over the past century and especially the last decade. But for some reason, recent reports that ocean currents and salinity are changing unusually fast trouble me even more. Perhaps it's because I can remember as a kid, my grandfather the meteorologist telling me about how ocean currents and weather patterns were closely linked, but no one knew which caused which, and that they probably both affected each other. Our difficulties predicting what will happen in this giant experiment remind me of Einstein's quote, "God does not care about our mathematical difficulties. He integrates empirically." One more very recent doozy: plants emit methane, a greenhouse gas 25 times more potent than CO2, and they emit more of it at higher temperatures. This appears to be a feedback loop that causes further acceleration of global warming. [4] [1] http://www.sciam.com/article.cfm?chanID=sa003&articleID=00020983-B238-1384-B23883414B7F0000 [2] http://www.techcentralstation.com/120205F.html [3] http://www.whoi.edu/institutes/occi/currenttopics/abruptclimate_joyce_keigwin.html [4] http://www.thestar.com/NASApp/cs/ContentServer?pagename=thestar/Layout/Article_Type1&c=Article&cid=1137019812913&call_pageid=968332188854&col=968350060724