Pamela and all, That is a good blog written by Cliff Mass. Sensible and realistic. Thanks for pointing it out. I'm not a climatologist; I'm a biochemist. Still, I took some thermodynamics a very long time ago. There is nothing contradictory in the weather we are seeing just now and the proposition that we humans are warming the climate unnaturally. The Earth's atmosphere-ocean system is a huge heat engine. The gasoline or diesel engine in your car or truck is a much simpler heat engine. Both sorts of "engine" are governed by thermodynamics. The data are irrefutable: The earth's atmosphere and oceans are warming at a rate much faster than the history of the last 1,000,000 years or so suggest they should be. The difference between 100,000 years ago and today is the presence and consequences of about 6 billion additional members of the species Homo sapiens. Why are some parts of North America and Europe colder this winter? Because the Earth's atmospheric engine is accelerating, fueled by the extra heat accumulating under our CO2 blanket. The more energy you put into a system, the farther away from equilibrium you can drive it. Give the engine more energy, and you can drive it up steeper gradients. The jet stream loops north in Alaska and south in the Midwest, when it should be somewhere in between, It is being driven away from equilibrium. We are driving the atmosphere and ocean to reward us with hotter summers, only occasionally colder winters, more and drier droughts and deadlier floods. It's getting more energetic and therefore more extreme. We still have the accelerator pedal pressed hard against the floorboard. Global climate change is going to affect what plants we can grow, where and how we grow them. I expect to see more extinctions of rare plant species. I might eventually have to spend more to cool my greenhouses in summer than I do now to heat them in my Indiana winters, if I live a few decades more (you can see that I'm very optimistic about progress in biomedical science). This is a good time to experiment more with growing plants not normally hardy in your climate, while planning future precautions to protect the ones now living happily in your garden or woods. Jim Shields At 09:47 AM 1/14/2010 -0800, you wrote: >Justin, > >Not to hijack the plant discussion, but since you ask about cold events and >global warming, I recommend http://cliffmass.blogspot.com/. Cliff Mass is a >University of Washington atmospheric scientist who communicates clearly. He >is a scientist, not an ideologue. Try these 2009 postings: January 5, >August 9, 17, and 22, December 15 and 21. These should answer your >question. > >Pamela ************************************************* Jim Shields USDA Zone 5 Shields Gardens, Ltd. P.O. Box 92 WWW: http://www.shieldsgardens.com/ Westfield, Indiana 46074, USA Tel. ++1-317-867-3344 or toll-free 1-866-449-3344 in USA