The U.S. just had its 2nd-warmest year on record, scope of warmth was 'unparalleled'
The U.S. had its second-warmest year on record in 2016, with every single state having a warmer-than-average year, according to a report released Monday by the National Oceanic and Atmospheric Administration (NOAA).
"The breadth of the 2016 warmth is unparalleled in the nation's climate history," NOAA scientists wrote in their annual climate report.
While records were toppled virtually everywhere, Alaska earned the title of having the most unusually warm year.
Alaska, which is America's only Arctic state, had an average annual temperature of 31.9 degrees Fahrenheit, which was 5.9 degrees Fahrenheit above average. The state had its second-warmest winter, warmest spring, second-warmest summer and a warmer-than-average fall.
This wound up being the third straight warmest year on record in Alaska, where temperature records go back 92 years.
According to NOAA, Barrow, which is the northernmost city in the country, was 7.1 degrees Fahrenheit above average. For the first time in Alaska's climate record, its average spring temperature hit 32 degrees Fahrenheit, or 0 degrees Celsius.
Since 1925, Alaska has seen an average temperature increase of 0.30 degrees Fahrenheit per decade.
Nationally in 2016, the lower 48 states had an average annual temperature of 54.9 degrees Fahrenheit, which was 2.9 degrees Fahrenheit above the 20th century average. This ranks just behind 2012, when the annual average temperature was 55.3 degrees Fahrenheit.
Remarkably, 2016 marks the 20th straight year of above-average continental U.S. temperatures. Since 1895, NOAA found, the lower 48 states have observed an average temperature increase of 0.15 degrees Fahrenheit per decade.
Last year now ranks in at least the top seven warmest years on record for every state.
"No other year had as many states breaking or close to breaking their warmest annual average temperature," NOAA said in the report.
The year featured an extremely lopsided ratio between record highs and record lows, at 5.7-to-1. According to the nonprofit climate research and journalism group Climate Central, this is the highest such ratio since consistent records began in 1920. In particular, there were an unusually high number of overnight record warm overnight temperatures.
On a map of record warm overnight low temperatures, 2016's climate painted the country red, with 93 percent of the continental U.S. seeing warm minimum temperature extremes last year.
The average low temperature for the country was 43.1 degrees Fahrenheit, which beat the old record set in 2012 by about 0.2 degrees.
One measure of how unusual the climate of 2016 was in the U.S. can be found in NOAA's Climate Extremes Index, which keeps track of temperature, precipitation and other extremes. For 2016, this index was the third-highest on record, behind only 1998 and 2012. Record daytime highs and record warm overnight low temperatures were a major contributor to this high ranking, NOAA stated.
The climate of 2016 had links to El Niño, which waned in the spring, as well as human-caused global warming, which has been leading to an array of climate shifts in the U.S. including rapid warming in Alaska.
Last year, the U.S. experienced 15 weather and climate disasters with losses exceeding $1 billion, with a total of 138 fatalities, NOAA found. Of these billion dollar disasters, four were inland floods -- double the typical number of such events. NOAA has been keeping track of these types of costly disasters since 1980.
The U.S. temperature data precedes an anticipated announcement that 2016 was the warmest year on record globally, which is due on Jan. 18. The European Copernicus Climate Service has already found that 2016 broke a global record, but more data is still being analyzed.
Andrew Freedman is Mashable's Senior Editor for Science and Special Projects. Prior to working at Mashable, Freedman was a Senior Science writer for Climate Central. He has also worked as a reporter for Congressional Quarterly and Greenwire/E&E Daily. His writing has also appeared in the Washington Post, online at The Weather Channel, and washingtonpost.com, where he wrote a weekly climate science column for the "Capital Weather Gang" blog. He has provided commentary on climate science and policy for Sky News, CBC Radio, NPR, Al Jazeera, Sirius XM Radio, PBS NewsHour, and other national and international outlets. He holds a Masters in Climate and Society from Columbia University, and a Masters in Law and Diplomacy from The Fletcher School at Tufts University.
