The decade of 1998-2007 is the warmest on record, according to data sources obtained by the World Meteorological Organization (WMO). The global mean surface temperature for 2007 is currently estimated at 0.41°C/0.74°F above the 1961-1990 annual average of 14.00°C/57.20°F.

An already relentless melting of the Arctic greatly accelerated this summer, a warning sign that some scientists worry could mean global warming has passed an ominous tipping point. One even speculated that summer sea ice would be gone in five years.

Greenland’s ice sheet melted nearly 19 billion tons more than the previous high mark, and the volume of Arctic sea ice at summer’s end was half what it was just four years earlier, according to new NASA satellite data obtained by The Associated Press.

The Greenland ice sheet melted at a record rate this year, the largest ever since satellite measurements began in 1979, a top climate scientist reported on Monday.

“The amount of ice lost by Greenland over the last year is the equivalent of two times all the ice in the Alps, or a layer of water more than one-half mile (800 meters) deep covering Washington DC,” said Konrad Steffen of the University of Colorado at Boulder.

A report released by the World Wide Fund for Nature is warning that more than half of the Amazon rainforest could be gone by 2030 as a result of increased logging and decreased rainfall.

That in turn would release some 90 billion tons of carbon dioxide into the atmosphere, accelerating global warming and affecting rainfall over the world’s major agricultural areas.

The risks of food riots and malnutrition will surge in the next two years as the global supply of grain comes under more pressure than at any time in 50 years, according to one of the world’s leading agricultural researchers.

Recent pasta protests in Italy, tortilla rallies in Mexico and onion demonstrations in India are just the start of the social instability to come unless there is a fundamental shift to boost production of staple foods, Joachim von Braun, the head of the International Food Policy Research Institute, warned in an interview with the Guardian.