[+/-] Earth is getting darker and hotter

Scientists examining five decades of sunlight measurements have reached the disturbing conclusion that the amount of solar energy reaching the Earth's surface has been gradually falling. The cause is air pollution, but paradoxically, this "global dimming" may mean that global warming is a far greater threat to society than previously thought:

[I]t now appears the warming from greenhouse gases has been offset by a strong cooling effect from dimming - in effect two of our pollutants have been cancelling each other out.

This means that the climate may in fact be more sensitive to the greenhouse effect than previously thought.

If so, then this is bad news, according to Dr Peter Cox, one of the world's leading climate modellers.

As things stand, CO2 levels are projected to rise strongly over coming decades, whereas there are encouraging signs that particle pollution is at last being brought under control.

"We're going to be in a situation unless we act where the cooling pollutant is dropping off while the warming pollutant is going up.

"That means we'll get reducing cooling and increased heating at the same time and that's a problem for us," says Dr Cox.

Even the most pessimistic forecasts of global warming may now have to be drastically revised upwards.

That means a temperature rise of 10 degrees Celsius by 2100 could be on the cards, giving the UK a climate like that of North Africa, and rendering many parts of the world uninhabitable.