March 17, 2007	Saturday	Safar 27, 1428

WASHINGTON, March 16: This winter was the warmest on record worldwide, says a US government report focusing on the changing climate.Last month an inter-governmental panel on climate change said human activities caused global warming, warning that it would linger for centuries.

The US National Oceanic and Atmospheric Administration found that volcanic gases, dust, pollution and other aerosol particles appear to have weakened the natural counter-balance to warming. The report, published in the Science journal, said combined land and ocean temperatures for December through February were 0.72 degrees Celsius above the average for the period since records began in 1880.

Most scientists attribute the rising temperatures to greenhouse gases produced by industrial activities, automobiles and other processes. These gases build up in the atmosphere and trap heat from the sun somewhat like a greenhouse.

Also contributing to this winter's record warmth was an El Nino, a periodic warming of the tropical Pacific Ocean. It was particularly strong in January — the warmest January ever — but the ocean surface has since begun to cool.

The report noted that in the Northern Hemisphere the combined land and water temperature was the warmest ever. In the Southern Hemisphere, where it was summer, the temperature was 0.6 degree Celsius above average and the fourth warmest.