"From 1875 to 1975 internationally accepted records suggest that the average global temperature rose by a total of just 0.2ºC. It was only the 0.5ºC rise recorded in the fourth quarter of the last century that produced the hysteria that has sparked this gold rush among green entrepreneurs and investors.
There may well be a green business opportunity. But my advice to would-be investors is this: make sure you get out before the bubble bursts." Lord Nigel Lawson in Time magazine. LINK