July 10, 2012 View all news The GuardianFiona Harvey, environment correspondentClimate change researchers have been able to attribute recent examples of extreme weather to the effects of human activity on the planet's climate systems for the first time, marking a major step forward in climate research.The findings make it much more likely that we will soon - within the next few years - be able to discern whether the extremely wet and cold summer and spring so far experienced in the UK this year are attributable to human causes rather than luck, according to the researchers.Last year's record warm November in the UK - the second hottest since records began in 1659 - was at least 60 times more likely to happen because of climate change than owing to natural variations in the earth's weather systems, according to the peer-reviewed studies by the National Oceanic and Atmospheric Administration in the US, and the Met Office in the UK. The devastating heatwave that blighted farmers in Texas in the US last year, destroying crop yields in another record "extreme weather event", was about 20 times more likely to have happened owing to climate change than to natural variation.Read more Categorised in: Climate Change