News•April 22, 2014

March of Global Warming: Month 4th Warmest on Record

Though cool temperatures prevailed across the eastern U.S. and Canada through March, the month was the fourth warmest March on record globally, the National Oceanic and Atmospheric Administration announced Tuesday. It was the 38th March in a row with warmer-than-average temperatures.

This graphic shows how much temperatures around the world departed from the average March temperature in March 2014.
Click image to enlarge. Credit: NOAA

The ranking matches that from NASA data released earlier this month, and marks a jump from February, which was the 21st warmest on record globally.

“The change was primarily due to warmer-than-average temperatures over central Asia in March, compared with cooler-than-average temperatures in February,” said Jessica Blunden, a NOAA climate scientist and author of the monthly reports the agency releases.

Globally, the average temperature for March was 56.18°F, or 1.28°F above the 20th century average of 54.9°F, NOAA said. While much of North America (except the western U.S.) saw cool temperatures — this March was the coolest in the U.S. since 2002 — plenty of other places saw warmer-than-normal temperatures, including northern South America, most of Europe and much of Asia.RELATEDMarch Was Coldest in U.S. Since 2002
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In Europe, Slovakia saw its warmest March since 1871; Austria matched its second warmest since records began in 1767; and Norway saw its third warmest March since 1900, according to NOAA.

If April is also warmer-than-average — as every month since February 1985 has been — it will be the 350th warmer-than-normal month in a row. April is also expected to be the first month in human history where the monthly average of atmospheric carbon dioxide exceeds 400 parts per million, a sign of how much the greenhouse gas has increased since the 280 ppm that marked pre-industrial levels.

The warm March came on the heels of the eighth-warmest winter on record, globally. The entire period from January to March was the seventh warmest on record, NOAA said, at 1.08°F above the 20th century average of 54.1°F.

Where 2014 ultimately falls in the rankings may depend on whether an El Niño develops later this year, something NOAA scientists have said has a better than 50 percent chance of happening by this summer or fall. An El Niño event is marked by warmer-than-normal sea surface temperatures in the eastern tropical Pacific Ocean, and is accompanied by shifts in atmospheric wind patterns. El Niño years are typically warmer than normal globally.

The global average temperature wasn’t the only sign of warming in March. The maximum extent of Arctic sea ice, reached on March 21, was the fifth smallest on record, and snow cover across the Northern Hemisphere was the sixth smallest extent in the 48-year record.