Sunspot activity has not resumed up after hitting an 11-year low in March last year, raising fears that - far from warming - the globe is about to return to an Ice Age.

ice age
©Reuters
Chop and change ... scientists says we should be less concerned by global warming and more worried about a new Ice Age


Astronaut and geophysicist Phil Chapman, the first Australian to become an astronaut with NASA, said pictures from the US Solar and Heliospheric Observatory showed no spots on the sun.

He said the world cooled quickly between January last year and January this year, by about 0.7C.

"This is the fastest temperature change in the instrumental record, and it puts us back to where we were in 1930," Dr Chapman writes in The Australian today.

"If the temperature does not soon recover, we will have to conclude that global warming is over."

The Bureau of Meteorology says temperatures in Australia have been warmer than the 1960-90 average since the late 1970s, barring a couple of cooler years, and are now 0.3C higher than the long-term average.

A sunspot is a region on the sun that is cooler than the rest and appears dark.

Some scientists believe a strong solar magnetic field, when there is plenty of sunspot activity, protects the earth from cosmic rays, cutting cloud formation, but that when the field is weak - during low sunspot activity - the rays can penetrate into the lower atmosphere and cloud cover increases, cooling the surface.

But scientists from the US National Centre for Atmospheric Research in Bolder, Colorado published a report in 2006 that showed the sun had a negligible effect on climate change.

The researchers wrote in the journal Nature that the sun's brightness varied by only 0.07per cent over 11-year sunspot cycles, and that that was far too little to account for the rise in temperatures since the Industrial Revolution.

Dr Chapman proposes preventive, or delaying, moves to slow the cooling, such as bulldozing Siberian and Canadian snow to make it dirty and less reflective. "

My guess is that the odds are now at least 50:50 that we will see significant cooling rather than warming in coming decades," he writes.