WASHINGTON • Boosted by a historic heatwave in Europe and unusually warm conditions across the Arctic and Eurasia, the average temperature of the planet soared to its highest level ever recorded last month.
According to data released on Monday by Nasa, the global average temperature was 0.93 deg C above the June norm (based on a 1951 to 1980 baseline), easily breaking the previous June record of 0.82 deg C, set in 2016, above the average.
The month was punctuated by a severe heatwave that struck Western Europe in particular during the last week, with numerous records for the all-time hottest temperature falling in countries with centuries-old data sets.
Notably, 13 locations in France surpassed their highest temperature ever recorded. The heatwave's highest temperature of 45.9 deg C, posted in Gallargues-le-Montueux, was 3.2 deg C above the old record, set during an infamous heatwave in July and August 2003.
Nasa is the second institution to confirm that it was the earth's hottest June, as the Copernicus Climate Change Service had already determined that last month was the warmest such month on record for Europe and globally.
June featured unusually mild conditions in the Arctic, particularly in Greenland, where the melt season got off to an early start.
July is picking up right where June left off.
Mr Zeke Hausfather, a climate scientist based in Berkeley, California, tweeted that the month so far ranks as the hottest on record, narrowly ahead of 2017, the previous record holder.
Mr Michael Mann, a climate scientist at Pennsylvania State University, tweeted: "If this July turns out to be the warmest July (it has a good shot at it), it will be the warmest month we have measured on earth."
Like June, July has featured some notable high-temperature extremes, including in Alert, Canada, the northernmost permanently inhabited spot on the planet less than 966km from the North Pole.
It hit a record high of 21 deg C on Sunday, breaking the previous record of 20 deg C.
"It is quite phenomenal as a statistic; it is just one example among hundreds and hundreds of other records established by global warming," Dr Armel Castellan, a meteorologist at the Canadian Environment Ministry, said on Tuesday.
The temperature was recorded on Sunday in Alert, a permanent military base on the 82nd parallel which intercepts Russian communications and which has been home to a weather station since 1950.
In addition, Alaska last week posted its hottest two days on record, highlighted by a temperature of 32.2 deg C in Anchorage for the first time.
The June monthly record and July's toasty first half raises the odds that 2019 could make a run for a top-three finish for warmest year, rather than top five.
According to data from Nasa and the National Oceanic and Atmospheric Administration, nine of the 10 warmest years on record have occurred since 2000, a trend that scientists have tied mainly to human emissions of greenhouse gases, which scientists say are trapping extra heat in the atmosphere.
Last October, a landmark United Nations report warned that time is running out to avert a global disaster and that avoiding climate chaos will require an unprecedented transformation of society and the world economy.
WASHINGTON POST, AGENCE FRANCE-PRESSE