The globally-averaged temperature for May 2012 marked the second warmest May since record keeping began in 1880. May 2012 also marks the 36th consecutive May and 327th consecutive month with a global temperature above the 20th century average.
May 2012 Selected Climate Anomalies and Events
Most areas of the world experienced much warmer-than-average monthly temperatures, including nearly all of Europe, Asia, northern Africa, most of North America and southern Greenland. Only Australia, Alaska and parts of the western U.S.-Canadian border region were notably cooler than average.
With the dissipation of La Niña in April, ocean conditions in May were "ENSO neutral." According to NOAA's Climate Prediction Center, there is a 50 percent chance that El Niño conditions will emerge during the second half of 2012.
Global temperature highlights: May
- The combined average temperature over global land and ocean surfaces for May was second warmest on record for May, behind 2010, at 59.79°F (15.46°C) or 1.19°F (0.66°C) above the 20th century average. This was the warmest monthly departure from normal since November 2010. The margin of error associated with this temperature is ±0.13°F (0.07°C).
- May marked the 36th consecutive May and 327th consecutive month with a global temperature above the 20th century average. The last below-average temperature May was May 1976 and the last below-average temperature month was February 1985.
- The global land surface temperature for May was 2.18°F (1.21°C) above the 20th century average of 52.0°F (11.1°C), the all-time warmest May on record. The margin of error is ±0.25°F (0.14°C).
- Warmer-than-average monthly temperatures occurred across much of the Northern Hemisphere while cooler-than-average temperatures occurred in parts of the Southern Hemisphere.
- Spain observed its fourth warmest May since national records began in 1960 at 4.9°F (2.7°C) above average.
- The nationally-averaged daytime temperature in Australia was near average (+0.5°C), while the average nighttime temperature was well below average (-2.9°C), ranking as the fifth coolest May nighttime temperature in that country's 63-year period of record.
- For the ocean, the May global sea surface temperature was 0.81°F (0.45°C) above the 20th century average of 61.3°F (16.3°C), or 10th warmest May on record. The margin of error is ±0.07°F (0.04°C).
- Neutral ocean conditions continued during May as sea surface temperatures continued to warm across the equatorial Pacific Ocean. According to NOAA's Climate Prediction Center, there is a 50 percent chance that El Niño conditions will emerge during the second half of 2012. In addition to influencing seasonal climate outcomes in the United States, El Niño is often, but not always, associated with global temperatures that are higher than temperatures in the neutral and La Niña phases.
Global temperature highlights: March-May
- The combined average temperature over global land and ocean surfaces for the March-May months was 1.06°F (0.59°C) above the 20th century average of 56.7°F (13.7°C), making it seventh warmest March-May period on record. The margin of error associated with this temperature is ±0.14°F (0.08°C).
- The global land surface temperature was 2.02°F (1.12°C) above the 20th century average of 46.4°F (8.1°C), making it fourth warmest March-May on record. The margin of error is ±0.25°F (0.14°C). Record April and May warmth in the Northern Hemisphere led to the warmest spring on record with a large temperature departure of 2.48°F (1.38°C) above the long-term average. That warmth was most pronounced across central Eurasia and most of North America. It was cooler than average across Alaska in the Northern Hemisphere and Australia in the Southern Hemisphere.
- The United States reported its warmest spring on record with 31 states in the eastern two-thirds of the country experiencing record warmth. The national temperature was 5.2°F (2.9°C) above its long-term average, surpassing the previous record by 2.0°F (1.1°C).
- In central Europe, Austria reported its seventh warmest spring since records began in 1767. In the east, the district of Lienz was just 0.4°F (0.2°C) short of the record warmth of May 2007.
- The Southern Hemisphere autumn was cooler-than-average across most of Australia with daytime temperatures 0.67°F (0.37°C) below average and nighttime temperatures ranking as fourth lowest on record (-1.67°F / 0.9°C), or lowest since 1994. La Niña, which tends to have a cooling influence over the region, ended during the season.
- For the ocean, the March-May global sea surface temperature was 0.70°F (0.39°C) above the 20th century average of 61.0°F (16.1°C), tying with 2011 as 11th warmest March-May on record. The margin of error is ±0.07°F (0.04°C).
Polar sea ice and precipitation highlights: May
- The average Arctic sea ice extent during May was 3.5 percent below average, resulting in the 12th smallest May sea ice extent on record since satellite records began in 1979.
- On the opposite pole, Antarctic sea ice during May 2012 was 2.4 percent above average and ranked as 15th largest May extent in the 34-year period of record.
- The Northern Hemisphere snow cover extent during May 2012 was much below average and ranked as second smallest May snow cover extent in the 46-year period of record. Eurasian snow cover extent was its all-time smallest May extent on record and the North American snow cover extents ranked its eighth smallest May extent on record.
- With the dissipation of La Niña in April, below-average precipitation fell across Australia in May with an average amount that was 60 percent of the monthly average. Western Australia reported its fifth driest May with precipitation just 22 percent of average.
- Spain was dry in May with average precipitation at 60 percent of the monthly average. The country's Mediterranean regions and archipelagos were the driest regions with precipitation less than 25 percent of average. In the east, stations in Murcia and Castellon reported its driest Mays on record.
- Much of India was drier than average for the month as the country anticipated the onset of its annual southwest monsoon season.
Global temperature highlights: Year to Date
- On the heels of a relatively mild first quarter, warmth during April and May pushed 2012 close to a top 10 warm status for the year to date. The combined global land and ocean average surface temperature for the January-May period was 0.90°F (0.50°C) above the 20th century average of 55.5°F (13.1°C), marking the 11th warmest such period on record. The margin of error is ±0.16°F (0.09°C).
- The January-May worldwide land surface temperature was 1.53°F (0.85°C) above the 20th century average, marking the 10th warmest such period on record. The margin of error is ±0.38°F (0.21°C).
- The global ocean surface temperature for the year to date was 0.67°F (0.37°C) above average and ranked as the 12th warmest such period on record and the coolest since 2008. The margin of error is ±0.07°F (0.04°C).
Materials provided by National Oceanic and Atmospheric Administration. Note: Content may be edited for style and length.