DOHA, Qatar — An area of Arctic sea ice bigger than the United States melted this year, according the U.N. weather agency, which said the dramatic decline illustrates that climate change is happening “before our eyes.”

In a report released at U.N. climate talks in the Qatari capital of Doha, the World Meteorological Organization said the Arctic ice melt was one of a myriad of extreme and record-breaking weather events to hit the planet in 2012. Droughts devastated nearly two-thirds of the United States as well western Russia and southern Europe. Floods swamped west Africa and heat waves left much of the Northern Hemisphere sweltering.

The dire climate news — following on the heels of a report Tuesday that found melting permafrost could significantly amplify global warming — comes as delegates from nearly 200 countries struggled for a third day to lay the groundwork for a deal that would cut emissions in an attempt to ensure that temperatures don’t rise more than 2 degrees C (3.6 degrees F) over what they were in preindustrial times. Temperatures have already risen about 0.8 degrees C (1.4 degrees F), according to the latest report by the IPCC.

MICHAEL CASEY,AP Environment Writer
Karl Ritter contributed to this report.