Our global temperature continued its upward trend last month with May 2017 marking not only the third warmest May on record but also closing out the planet’s second warmest March to May period, known as meteorological spring in the northern hemisphere.
According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for May – over both land and sea surfaces – was 60.09°F, which is 1.49°F above the 20th-century average. Only May 2015 and 2016 were warmer.
This May also marked the 389th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.
The three-month period of March, April, and May was also unusually warm. NOAA reports that Earth’s average temperature for the season was 1.66°F above the 20th century average of 56.7°F. That makes it the second warmest such period on record, trailing only the 2016 season.
While heat dominated most of the planet this spring, some places were particularly warm, including much of Europe and North America. Here in the contiguous US, it was our eighth warmest spring on record.
These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in May, which means there was neither an El Niño nor a La Niña in the Pacific to influence global weather patterns.
Year to date, the first five months of 2017 were the second warmest such period of any year on record. Global temperature records date back to 1880.