A newly released peer-reviewed study has found compelling evidence that human-caused climate change contributed to at least 6 of 12 extreme weather/climate events that occurred on five continents and the Arctic last year.
The NOAA map below shows the locations of the 12 extreme events from last year.
A total of 18 different research teams from around the world assessed a wide variety of potential contributing factors to these major extreme events that, in many cases, had large impacts on society.
Below are excerpts of the key findings from the NOAA news report.......
--The 2012 spring and summer heat waves in the U.S. can be mainly explained by natural atmospheric dynamics, however, human-induced climate change was found to be a factor in the magnitude of warmth and was found to have affected the likelihood of such heat waves.
--The record-setting impacts of Sandy were largely attributable to the massive storm surge and resulting inundation from the onshore-directed storm path coincident with high tide. However, climate-change related increases in sea level have nearly doubled today's annual probability of a Sandy-level flood recurrence as compared to 1950.
--The extremely low Arctic sea ice extent in summer 2012 resulted primarily from the melting of younger, thin ice from a warmed atmosphere and ocean. This event cannot be explained by natural variability alone.
--The magnitude of the extreme rainfall experienced over southeastern Australia between October 2011 and March 2012 was mainly associated with La Niña conditions. However, the likelihood of above-average precipitation during March was found to have increased by 5 percent to 15 percent because of human influences on the climate.
--Human-induced climate change had little impact on the lack of precipitation in the central United States in 2012.
Despite the rapid warming trend and resulting loss of permafrost, methane levels along Alaska's Arctic slope have been fairly stable over the past 29 years.
This year could challenge 2012 for the lowest sea ice extent minimum in the satellite record for the Arctic region.
Large portions of northern North America have experienced a greening trend over the past three decades.
New research explains why the Southern ocean surrounding Antarctica has not warmed like the rest of the world's oceans.
The warming influence of carbon dioxide has increased by 50 percent above pre-industrial levels during the past 25 years, according to NOAA.
The incredible streak of record-breaking global warmth continued through April.