European and American cold spells; are they evidence of global cooling, climate change or just weather?
Weather, mainly. You expect some regions to be unusually warm, and some unusually cold, because of random fluctuations (weather), but the overall trend (climate) is all too clear. There is the scary prospect that it’s caused by slowing of the Gulf Stream, but climate scientists now think that’s just an outside chance. However … With well over 90% certainty, increasing the more we learn, global warming is real, serious, unprecedented, driven mainly by human activity, and requires appropriate action.This conclusion is reached even after taking natural variation, such as that connected to the sunspot cycle, into account. See NSF overview: http://www.nsf.gov/news/special_reports/… and statement at http://royalsociety.org/displaypagedoc.a… endorsed by the [US] National Academy of Sciences, Chinese Academy
