It was also the warmest May that didn’t occur during an El Niño ocean warming in the tropical Pacific, according to University of Alabama in Huntsville atmospheric scientist John Christy.
The Earth System Science Center (ESSC), where Christy is director, determined that May was about 0.6 degrees Fahrenheit above seasonal normal for the month.
The warmest May on record was in 1998 and occurred during the warmest and most influential El Niño in the climate record.
The global seasonal average for that month was about 1.0 degree above normal.
Given that this year is already unusually warm, Christy says the potentially emerging El Niño in the Pacific could challenge the 1998 episode’s record.
“With the baseline so much warmer, this upcoming El Niño won’t have very far to go to break that (1.0 degree) record,” Christy said. “That isn’t to say it will, but even an average-sized warming event will have a chance to get close to that level.”
The ESSC uses data gathered by advanced microwave sounding units on NOAA and NASA satellites to get accurate temperature readings for nearly all regions of the world. This includes remote desert, ocean and rain forest areas where surface weather observations are not available.
Photo: Earth System Science Center