In 2011 temperatures around the globe were slightly cooler on average than in the two years before. Does that mean Global Warming has somehow ended? Or that it has never even existed? Global Ideas Climate Expert Anders Levermann (http://www.pik-potsdam.de/~anders/) explains why a cooler year does not contradict the reality of Global Warming.
How many years of cooling is needed to rule out natural variability as the explanation?
ReplyDeleteHow about the effects of increased or decreased solar activity as an explanation for natural variability in terms of warming and cooling?