According to new data from the National Oceanic and Atmospheric Administration (NOAA), the weather of the continental U.S. in 2012 was exceptional — and not necessarily in the good sense. It was not only the hottest year on record, but it also surpassed the previous high, set in 1998, by a full degree. As the New York Times noted, “The temperature differences between years are usually measured in fractions of a degree, but last year’s 55.3 degree average demolished the previous record.”
The NOAA report, “State of the Climate, National Overview,” details the myriad unusual weather patterns over the course of the year. For example, March 2012 was the warmest on record, with a prolonged heat wave in the Midwest and Northeast that broke thousands of local records. Precipitation in the continental U.S. has been increasing over more than a century at a rate of 0.16 inch a decade, but last summer drought afflicted more than half the country. Meanwhile, Florida had 40% more rain than normal. Overall, however, total precipitation was 10% below average, just 26.57 inches.
The litany of tornadoes, storms and other extreme weather didn’t let up, of course. Hurricane Isaac and megastorm Sandy brought destruction to the East Coast, while wildfires raged in Colorado and other western and central states. More Americans have started to see a connection between climate change and human activity, something the vast majority of scientists believe.
Other findings of the NOAA report include:
- “In 2012, the contiguous United States (CONUS) average annual temperature of 55.3°F was 3.2°F above the 20th century average, and was the warmest year in the 1895-2012 period of record for the nation. The 2012 annual temperature was 1.0°F warmer than the previous record warm year of 1998.”
- “On a statewide and seasonal level, 2012 was a year of both temperature and precipitation extremes for the United States. Each state in the CONUS had annual temperatures which were above average. Nineteen states, stretching from Utah to Massachusetts, had annual temperatures which were record warm. An additional 26 states had one of their 10 warmest years.”
- “Seasonal highlights in 2012 include the fourth warmest winter (December 2011-February 2012), with warmer-than-average conditions across a large portion of the country.”
- “Much of the CONUS was drier than average for the year. Below-average precipitation totals stretched from the Intermountain West, through the Great Plains, into the Midwest and Southeast. Nebraska and Wyoming were both record dry in 2012. Nebraska’s annual precipitation total of 13.04 inches was 9.78 inches below average, and Wyoming’s annual precipitation total of 8.08 inches was 5.09 inches below average. New Mexico, Colorado, Kansas, Missouri, Illinois, Arkansas, Georgia, and Delaware had a top ten dry year.”
- “The large area of dry conditions in 2012 resulted in a very large footprint of drought conditions, which peaked in July with about 61% of the CONUS in moderate-to-exceptional drought.”
- The extensive drought led to both large-scale agriculture problems and record-breaking wildfires in the Midwest, Plains and Mountain West. Approximately 7 million acres burned during the three summer months.
- Since 2010 the NOAA has compiled a list of top 10 weather events for each year. For 2012, these include: Hurricane Sandy and Hurricane Isaac; the U.S. drought and wildfires; a March outbreak of severe weather in the Ohio Valley and Southeast, and near-record low Great Lakes levels.
The report has a wealth of data for specific times and regions. More detailed analysis can also be found through the Climate Monitoring home page.
A draft of the 2013 federal National Climate Assessment report also discusses similar patterns:
Americans are noticing changes all around them. Summers are longer and hotter, and periods of extreme heat last longer than any living American has ever experienced. Winters are generally shorter and warmer. Rain comes in heavier downpours, though in many regions there are longer dry spells in between. Other changes are even more dramatic. Residents of some coastal cities see their streets flood more regularly during storms and high tides. Inland cities near large rivers also experience more flooding, especially in the Midwest and Northeast. Hotter and drier weather and earlier snow melt mean that wildfires in the West start earlier in the year, last later into the fall, threaten more homes, cause more evacuations, and burn more acreage.
A related 2013 study published in the journal PLoS One, “Record-Breaking Early Flowering in the Eastern United States,” analyzes “long-term flowering records initiated by Henry David Thoreau in 1852 and Aldo Leopold in 1935” to determine how climate change is affecting the life cycle of plant species. The findings “demonstrate that record-breaking spring temperatures in 2010 and 2012 in Massachusetts, USA, and 2012 in Wisconsin, USA, resulted in the earliest flowering times in recorded history for dozens of spring-flowering plants of the eastern United States.” Likewise, a 2013 study published in Science, “Plant-Pollinator Interactions over 120 Years: Loss of Species, Co-Occurrence and Function,” uses historical data gathered by the naturalist Charles Robinson and finds significant climate change-related impacts on the behavior of bees in the state of Illinois.
A 2012 report by the U.N. Intergovernmental Panel on Climate Change, “Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation,” provides a broader global picture of the possible scope and power of future climate change-driven events.
Tags: global warming, disasters
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