June 18, 2015

Report from the National Centers for Environmental Information

Excerpt

The combined average temperature over global land and ocean surfaces for May 2015 was the highest for May in the 136-year period of record, at 0.87°C (1.57°F) above the 20th century average of 14.8°C (58.6°F), surpassing the previous record set just one year ago by 0.08°C (0.14°F). This ties with February 1998 as the fourth highest monthly departure from average for any month on record. The two highest monthly departures from average occurred earlier this year in February and March, both at 0.89°C (1.60°F) above the 20th century average for their respective months.

The average global temperature across land surfaces was 1.28°C (2.30°F) above the 20th century average of 11.1°C (52.0°F), tying with 2012 as the highest May temperature on record. Most of Earth’s land surfaces were warmer than average or much warmer than average, according to the Land & Ocean Temperature Percentiles map above, with record warmth across most of Alaska, parts of tropical South America, much of southern Africa and The Middle East, and parts of northwestern Siberia. Only part of the central United States, far west central Australia, and part of Far East Russia observed temperatures characterized as “cooler than average” for May.