Year in Review
According to NOAA scientists, 2011 was a record-breaking year for climate extremes, as much of the United States faced historic levels of heat, rain or snow, flooding, and severe weather. As part of its annual review of Earth's climate, NOAA scientists and other experts from around the country identified and ranked the year's most significant national climate or weather events. The voters consider factors such as the scope and unusualness of the event, its immediate human and economic impact, and whether it is emblematic of climate trends or variability. These images showcase the events that will go down in NOAA's record books as 2011's most significant climate or weather events.