munich re
Though of course by "natural" we're thinking of with-a-human-contribution. My text is taken from the book of Grauniad:
On Friday a team of researchers in Boston calculated that even with only a 2C rise, summer temperatures now regarded as "extreme" will become normal. This is the second such warning from the US this summer. Europeans in 2003 and Russians in 2010 had lethal experience of heat waves. ... Munich Re predicted that 2011 - on the evidence of the first six months alone - will be the costliest year ever for disasters triggered by natural hazard. Total global losses by June had…