On a temperature map these days, Siberia shows up as a bright red splotch, like a widespread rash on the Earth’s surface. This region has seen persistently extreme temperatures since the winter, which has led to a damaging Arctic oil spill, sparked early outbreaks of large wildfires and helped vault global temperatures to new milestones.

Unusually high temperatures in Siberia, along with above-average temperatures elsewhere, propelled the globe to set or tie the record for the warmest May, according to data released last week by four atmospheric research groups that keep track of global temperatures.

A winter heat wave throughout Russia became such a hot-button issue that it was the first question posed to President Vladimir Putin during his four-plus-hour end-of-year news conference in December.

“As you know, Russia is a northern country, and 70 percent of our territory is located in the north latitudes,” Putin responded. “Some of our cities were built north of the Arctic Circle, on the permafrost. If it begins to thaw, you can imagine what consequences it would have. It’s very serious.”

Thaw triggers fuel spill

The melting permafrost inadvertently caused a major fuel spill in Siberia earlier in the month. A fuel tank ruptured at a power plant in Norilsk — above the Arctic Circle in north-central Russia — leaking at least 20,000 tons of diesel fuel into the nearby Ambarnaya River, believed to be the worst spill in the Russian Arctic’s history.

Permafrost thawing across Siberia, linked to climate change, has caused widespread problems such as buckled roads, collapsed homes and disruptions to traditional herding and agriculture. It was that unstable foundation that Norilsk Nickel, the parent company of the plant, blamed for the fuel reservoir’s rupture.

During a televised video conference meeting, Putin scolded Norilsk Nickel’s chief executive, Vladimir Potanin, for not replacing the fuel tank “in a timely manner,” which would have prevented the leak. One issue is that the many factories and plants located on permafrost are not required to regularly monitor ground stability, said Vasily Yablokov, projects coordinator for the Russian branch of Greenpeace.

The cleanup of the spill will take years and is especially challenging because of its remote location, with no roads in the area. Environmentalists were dismayed by the regional governor’s announcement that the pollution reached nearby Lake Pyasino.

“It’s impossible to live in this mix of water and fuel, so of course, fish there died,” Yablokov said. “Now we can call this a dead lake.”

A study published in the journal Nature Communications in 2018 suggests the Norilsk spill will not be the last permafrost-related oil or gas incident. The study, which examined the effects of climate change on Arctic infrastructure, found that nearly half of the “globally important” oil and gas fields in the Russian Arctic are in areas where the thaw of near-surface permafrost could cause severe damage by 2050.

Record warm winter continues through spring

During the spring, stubborn and sprawling areas of high pressure parked over the region resulted in parts of Siberia recording temperature departures from average that reached a staggering 18 degrees (10 degrees Celsius), according to the Copernicus Climate Change Service, which is an initiative of the European Union.

In western Siberia in particular, it was “by far” the warmest May on record, a Copernicus special report states.

For example, on May 22 the town of Khatanga, Siberia, located well north of the Arctic Circle, recorded a temperature of 78 degrees, some 46 degrees above normal. The typical maximum temperature for the day at that location is 32 degrees. The town obliterated its previous record high for the date of 54 by some 24 degrees and its monthly record of 68 by about 10 degrees.

According to the report on recent Siberian temperatures, the persistence of the warm anomalies stands out from the historical record.

In addition to the May record, the average temperatures in December through May period were record warm for the period dating back to 1979.

By pairing the data with NASA’s surface records that go back to 1880, Copernicus scientists found that this most recent six-month period is probably unprecedented since at least 1880.

These high temperatures have contributed to exceptional global warmth.

According to Copernicus, NASA and Berkeley Earth, the planet had its warmest May on record since 1880, whereas the National Oceanic and Atmospheric Administration ranks it as tied with 2016 for the warmest May.

The past seven Mays, from 2014 to 2020, have been the seven warmest Mays on record, NOAA found. In addition, the year is tracking as the second-hottest on record, with the odds favoring an outcome of 2020 narrowly edging out 2016 to become the hottest year, or coming in just behind for the No. 2 spot.

Whatever the ranking, it’s clear that the planet’s fever is worsening, rather than breaking, with self-reinforcing feedbacks kicking in across the Arctic in particular. Permafrost melt itself releases long-buried greenhouse gases into the atmosphere, such as carbon dioxide and methane.

Siberia’s abnormally warm weather also led to the region’s spring wildfire season kicking off earlier than usual; volunteer firefighters in Russia’s far east said they started smelling smoke just stepping outside, weeks earlier than usual.

Some of the April fires in eastern Russia dwarfed the infernos from this time last year, which ultimately roared through 7 million acres in total — about the size of Maryland — and sent smoke drifting as far as the United States and Canada. In Krasnoyarsk, about 2,500 miles east of Moscow, recent fires were 10 times larger than this time last year, he said. Farther to the east, in the Transbaikal Territory, the fires were three times larger.

Meanwhile, in the Alaskan Arctic, which has also seen sudden shifts to hotter and drier summers, wildfires are igniting in unusual locations such as in western parts of the state, close to the Bering Sea. In addition, lightning strikes were detected over the weekend all the way from Fairbanks to the state’s North Slope. Most of Alaska’s annual wildfires are ignited by lightning.

Khurshudyan reported from Moscow.