WASHINGTON, Aug 6 (Reuters) - Last year was one of the 10 hottest on record, with sea levels at record highs, Arctic ice at historic lows and extreme weather in various corners of the globe signaling a "new normal," scientists said Tuesday in the 2012 State of the Climate report.

Meant to be a guide for policymakers, the report did not attribute the changes in climate to any one factor, but made note of continued increases in heat-trapping greenhouse gases including carbon dioxide, methane and nitrous oxide.