MOSCOW — An unusually warm Russian December was what woke Dasha the bear.

Balmy temperatures melted the snow at the Bolsherechensky Zoo in the Omsk region, 1,700 miles east of Moscow, and interrupted hibernation for the brown bears.

“They probably decided that spring had come,” zoo spokeswoman Natalya Bolotova said.

After burrowing out of their hay beds, most ate a meal and went back to sleep — except for Dasha, a Himalayan. It didn’t get comfortably cool enough for her until Thursday.

Russians across the country can sympathize.

The nation is experiencing a winter heat wave that is 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 Thursday. A day earlier, Russia’s Hydrometeorological Research Center recorded Moscow’s warmest December temperature in 133 years (5.6 degrees Celsius, or 42 degrees Fahrenheit). The European part of Russia is experiencing weather that’s 5 to 8 degrees Celsius warmer than the norm for late December.

Putin responded that “nobody knows” the origins of global warming, but he acknowledged that it’s a serious issue and that Russia “must undertake maximum efforts to ensure that the climate does not change dramatically.”

“As you know, Russia is a northern country, and 70 percent of our territory is located in the north latitudes,” Putin said. “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.”

Scientists have concluded that modern-day global warming, including the warming observed throughout Russia, is almost entirely due to human emissions of heat-trapping greenhouse gases, such as carbon dioxide and methane.

Russia joined the Paris climate accord in September, one of the last countries to do so, but a month later, climate change legislation was watered down after objections from some businesses. That killed plans for individual carbon emissions quotas and a national carbon trading system.

Russia’s environment ministry has warned that the country is warming disproportionately fast compared with the rest of the world — 2.5 times quicker than the global average. The Siberian permafrost has already begun thawing, unearthing prehistoric mammoth remains. The region’s forest was ravaged by wildfires this summer, with the smog reaching major cities in the area.

Emerging research shows that the rapid warming taking place in the Arctic is causing the region to turn into a net source of greenhouse gases, in a long-feared climate feedback. A recent report published by the U.S. government found that the Arctic as a whole may be emitting greenhouse gases on the scale of Japan’s or Russia’s annual emissions, further complicating the task of limiting warming.

The effects in Moscow aren’t as extreme, but the Hydrometeorological Research Center said Monday that 2019 could be the capital city’s warmest on record. Residents are lamenting a December without the constant layer of snow that defines Russian winters, when what little light there is typically reflects off the white covering and brightens the days.

The website for a suburban ski resort features an apologetic bulletin that it’s currently closed because of the toasty conditions, adding, “Winter, do you remember that you are winter?”

At Moscow State University’s Apothecary Garden, primrose, rhododendron and snowdrops are among the plants that have blossomed prematurely. Like the Bolsherechensky Zoo’s bears, the plants believed that the moderate rainy days signaled springtime.

“Because the soil hasn’t frozen yet, they’ve mixed up the seasons,” head gardener Anton Dubenyuk said.

Protests tied to environmental issues, including those related to where Moscow’s trash gets dumped, have spread throughout Russia, arguably the most sustained activist movement. But a Levada Center poll from August, conducted at the time of Siberia’s forest fires, revealed that just 12 percent of Russians considered global climate change a concern for the spread of the fires.

“Russians believe in it,” said Vasily Yablokov, projects coordinator at Greenpeace. “They see the climate change. But they, like Putin, don’t know why it’s happening. . . . Not everybody connects it, but a lot of people tie this to being caused by humans.”

Alexander Rodin, head of the Moscow Institute of Physics and Technology’s environmental and planetary sciences program, said a warm start to winter once every 10 years isn’t that unusual. The greater concern is that this could represent another extreme in a year of them.

“We have more and more records,” Rodin said. “It’s the warmest day in the past 100 years, then the coldest day in 100 years and so on. This is a result of actual climate change because here in Russia, at least in the middle latitudes of Russia, the main effect of climate change is the increase of weather variations.”

That has locals concerned that this warm December could be followed by an especially cold January and February. Dubenyuk said the plants at the Apothecary Garden will survive if temperatures drop suddenly, but the flowers they’ve now presented will die and won’t return in the actual springtime.

Strolling through Moscow’s Gorky Park, landscape architect Lidia Leontieva pointed out how some greenery is accustomed to a blanket of snow over it this time of year, so to mimic that her team raised the soil around the roots and covered it with leaves. The stonecrop plants are uncovered because when the snow does fall, the flat flowers will look like white pillows — popular for photos. Instead, they’re a rusted purple now.

“I love snow,” Leontieva said. “It is so clean with the snow. I just love it when you enter the park early in the morning and there is snow everywhere, and since it is early there are no traces yet, nobody has walked or driven on it. It is so beautiful.”

Andrew Freedman contributed to this report.