WASHINGTON (Reuters) - Last month was the warmest May on record, the U.S. National Oceanic and Atmospheric Administration said on Tuesday.
It was also the 303rd consecutive month that was hotter than the 20th century global average for that month, according to Deke Arndt, chief of the climate monitoring at NOAA's National Climatic Data Center.
"Since February 1985, every single month has been warmer than its 20th century average," Arndt said by telephone from Asheville, North Carolina.
The long-term warming trend, along with reports that Arctic sea ice covered less of the ocean and snow covered less ground around the world in May, is consistent with the science of climate change, Arndt said.
Many climate scientists believe that Earth's surface is warming, due in part to the emission of heat-trapping greenhouse gases, including carbon dioxide.
In addition to a record-hot May, high temperature surface records -- for warmth on the planet's land and oceans -- were set for the period of March through May and for January through May, the data center said in a statement.
Looking only at global average land surface temperatures, May and the March-to-May period were also the warmest on record.
Global ocean surface temperatures for both May and March-to-May were the second-hottest on record, behind 1998, according to the data center.
The combined global land and ocean surface temperature for May was 59.84 degrees F (15.46 C), which was 1.24 degrees F (0.69 degrees C) above the 20th century average of 58.6 degrees F (14.8 degrees C).
The global land surface temperature for May was 53.87 degrees F (12.15 degrees C), which is 1.87 degrees F (1.04 degrees C) above the 20th century average of 52 degrees F (11.1 degrees C) -- the warmest on record.
The May worldwide ocean temperature, the second warmest ever recorded after 1998, was 62.29 degrees F (16.82 C), compared to the 20th century average of 61.3 degrees F (16.3 degrees C).
Most of Earth's land areas saw extraordinary warm temperatures, with the hottest showing up in eastern North America, eastern Brazil, eastern Europe, southern Asia, eastern Russia, and equatorial Africa. China's Yunnan province had its warmest May since 1951 while many locations in Ontario, Canada had their warmest May on record.
It was unusually cool across western North America, northern Argentina, interior Asia and Western Europe. Germany had its coolest May since 1991, its 12th coolest May on record.
(Editing by Cynthia Osterman)