Surface temperatures in Siberia were up to 10 degrees Celsius (18 degrees Fahrenheit) higher than average last month, making it the vast Russian region’s hottest May since records began in 1979, according to research by the Copernicus Climate Change Service (C3S), a program affiliated with the European Commission. Siberia’s warmer weather came as the world experienced its hottest May on record, the C3S findings show. According to climate scientist Martin Stendel, the temperature deviation in northwestern Siberia last month would happen only once in 100,000 years if it weren’t for climate change.
But in Siberia, it wasn’t just May that was warmer than usual — the region experienced periods of higher-than-average surface air temperatures throughout winter and spring, with warmer temperatures particularly from January, C3S found.
“It is undoubtedly an alarming sign,” said Freja Vamborg, a senior C3S scientist.
Siberia tends to see large temperature variations month-to-month and year-on-year, and there have been months in previous years when the temperature anomalies were larger than what the region has experienced in the past six months, C3S said. But, according to C3S, it’s unusual to see warmer-than-average temperatures for so many months in a row.
Although the Earth as a whole is warming, temperature rises don’t occur evenly across the planet, Vamborg said.
She said western Siberia stands out as a region that shows more of a warming trend with higher variations in temperature.
Scientists say the Arctic region is warming, on average, twice as quickly as the rest of the planet as a consequence of global warming. Russia recorded its hottest winter in the 140-year history of meteorological observations, state-run Hydrometeorological Center of Russia reported earlier this year.
Effects of warmer temperatures
The warmer temperatures already appear to be having negative impacts.
Earlier this month, Russian President Vladimir Putin ordered a state of emergency in the Siberian city of Norilsk after 20,000 tons of fuel spilled into a nearby river from a power station.
Nornickel, the energy company’s parent, said the foundation of the storage tank possibly sank due to thawing permafrost, highlighting the dangers increasingly warming temperatures pose to Arctic infrastructure and ecosystems, according to Russian state news agency TASS.
“Right now we can assume … that due to abnormally mild summer temperatures recorded in the past years, permafrost could have melted and the pillars under the platform could have sank,” said Nornickel chief operating officer Sergey Dyachenko, according to TASS.
Sergey Verkhovets, coordinator of Arctic projects for Russia’s WWF branch, said that the incident led to catastrophic consequences.
“We will be seeing the repercussions for years to come,” Verkhovets said. “We are talking about dead fish, polluted plumage of birds, and poisoned animals.”
Last year, wildfires ravaged the Arctic at unprecedented levels, spewing megatons of greenhouse emissions into the atmosphere, according to official Russian estimates.
CNN’s Mary Ilyushina and Frederik Pleitgen contributed to this story.