Every month the US National Oceanic and Atmospheric Administration release a series of highlights depicting the state of the previous months climate. January 2012s statistics have been released, and the lead story for many is that it was the 19th warmest January on record at 12.39°C (54.30°F), which is 0.39°C (0.70°F) above the 20th century average of 12.0°C (53.6°F).
However, there were two other important statistics to take from January’s State of the Climate.
Growth rate for Arctic sea ice throughout the month of January 2012 was the slowest in the satellite record, and the average sea ice extent was 7.5 percent below the average, ranking in as the fourth smallest January extent since record keeping began back in 1979.
The extent was 1.1 million square kilometres (425,000 square miles) below the average, and marks the 19th consecutive January and 128th consecutive month with below-average Arctic sea ice extent which does not bode well for the oncoming summer ice melt.
Conversely, Antarctic summer sea ice during January was 13.8 percent above the average, and the sventh largest sea ice extent on record since record keeping began.
The remaining highlights are listed below along with the monthly map of selected climate events for January 2012;
Global temperature highlights: January
- Separately, the global land surface temperature was 1.10°F (0.61°C) above the 20th century average of 37.0°F (2.8°C), making this the 26th warmest January on record. The margin of error is +/- 0.32°F (0.18°C). Warmer-than-average conditions occurred across most of North America, the northern latitudes of Europe and Asia, southern South America, and most of Australia. Cooler-than-average regions included China, Mongolia, Kazakhstan, south central Russia, much of the Middle East, northern India, north Africa, and southwestern Greenland.
- The Arctic Oscillation climate pattern played a role in temperatures in the Northern Hemisphere during January. The positive phase during the first half of the month contributed to well-below average monthly temperatures across Alaska and above-average temperatures across the contiguous United States. The negative phase during the second half of the month contributed to warmth in Canada and also to a cold snap that began during the last week in January across Central and Eastern Europe and north Africa.
- The January global ocean surface temperature was 0.54°F (0.30°C) above the 20thcentury average of 60.5°F (15.8°C), making it the 17th warmest January on record and coolest monthly ocean temperature since January 2008. The margin of error is +/- 0.07°F (0.04°C). The warmth was most pronounced across the north central and southwestern Atlantic Ocean, the central and western Pacific, and the southeastern Indian Ocean.
Polar Sea Ice and Precipitation Highlights
- Northern Hemisphere snow cover extent during January was slightly above average, with large differences between the North American and Eurasian land areas. Eurasia had its ninth largest snow cover extent in the 46-year period of record, where cold and snowy conditions dominated across central and Eastern Europe, as well as much of China. North America had its third smallest January snow cover extent, where much of the United States and southern Canada were warmer and drier than average, limiting snow cover.
- Monsoonal rains brought heavier-than-average rainfall to southwestern and southeastern Australia. Precipitation was also much above average in south Asia, part of eastern Russia, and southwestern Greenland. Much drier-than-average conditions were observed across northern Canada, the north central United States, eastern Brazil, and northern Sweden.