News•February 21, 2013

Warming Climate Yields Another Hot January: NOAA

January of 2013 continued the unbroken string of months with above-average global surface temperatures, tying with 1995 as the ninth-warmest such month on record since instrument records began in 1880, the National Oceanic and Atmospheric Administration (NOAA) said on Thursday. This marked the 335th straight month above the 20th century average, and the 37th straight warmer-than-average January.

The last cooler-than-average January occurred in 1976, and the last cooler-than-average month occurred in February 1985.

In other words, no one under the age of 28 has ever experienced a month in which global average surface temperatures were cooler-than-normal.

Global map showing the areas that were warmer than average (red) or cooler than average (blue) during the month of January.
Click on image to enlarge. Credit: NOAA.

January featured record warm temperatures across land areas in the Southern Hemisphere, especially in Australia, where a prolonged heat wave led to an outbreak of destructive wildfires. Australia set a national record for the hottest day in recorded history on January 7, with an average maximum temperature across the country of a sizzlingly warm 104.6°F.

Global ocean surface temperatures were the eighth-warmest on record, with neither El Niño or La Niña conditions present in the tropical Pacific Ocean, NOAA said. El Niño and La Niña events can affect global weather patterns, particularly during the winter months.

The drought in the U.S. continued to affect a majority of the lower 48 states, with little to no relief seen in much of the West, Southwest, and Great Plains.

Alaska, the eastern U.S., southern Greenland, Uzbekistan, and Australia experienced warmer-than-average temperatures during January, NOAA said. Parts of Canada, the Western U.S., and much of northern Europe and Asia were colder-than-average for the month.

The Northern Hemisphere saw above-average snow cover extent for January, with the sixth largest in the 47-year record, or 730,000 square miles above the 1967-2013 average. The western U.S., eastern China, and much of Europe had above-average January snow cover. While winter Northern Hemisphere snow cover has grown at a rate of about 0.1 percent per decade, spring Northern Hemisphere snow cover has shrunk by about 2.2 percent.

In recent years there has been a trend toward above-average winter snow cover in the Northern Hemisphere, but a sharp decrease in spring snow cover, which studies have shown is consistent with the influence of global warming.

The January Arctic sea ice extent was the sixth-smallest monthly ice extent on record, at 7.2 percent below the 1979-2000 average. According to NOAA, the 10 years since 2004 have seen the 10 smallest January sea ice extents on record in the Arctic.

Arctic sea ice extent reached a record low in 2012, and the rapid meltback of sea ice is widely viewed as an indication of how global warming is reshaping the Arctic, with possible consequences for North American weather, in addition to geopolitical ramifications.

In contrast, Antarctic sea ice extent was the seventh largest on record for the month of January. That is also consistent with global warming projections.