This winter, another blizzard swept over the largest cities in America - New York and Washington. It's strange - after all, everyone around is talking about global warming … Where is it? And how does it affect the weather and snowfall? The BBC Earth columnist is looking for answers to these questions.
This "end of snow" is already a tradition. Not a year goes by without someone else feeling the harsh consequences of a massive snowfall.
Considering that as a result of anthropogenic impact on the climate, the average annual temperature in the world is constantly increasing, many people wonder where such strong blizzards come from then.
Can global warming be accompanied by so many snow cataclysms?
One possible answer that inevitably comes to mind after another heavy snowfall: climate change is a myth.
However, even if we take for granted the unanimous opinion of the majority of scientists that the climate is indeed changing, it is still unclear what is the reason for such a rainfall.
Maybe the world just isn't warmer enough for all the snow to melt?
The correct answer turned out to be rather unexpected. The unusually high level of snowfall in the form of snow is actually a natural consequence of global warming.
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This may seem paradoxical, but only because often in our understanding the only condition for snow to fall is cold weather.
In fact, heavy snow requires something else, namely high humidity.
Moisture tends to accumulate in areas of warm air, as for every one degree Celsius increase in temperature, the atmosphere's ability to hold water vapor increases by 7%.
Climate change has increased these areas of warm air, which helps explain why the East Coast of the United States was buried under snow in late January.
Due in part to climate change, the Atlantic Ocean is now warmer than it was just a few decades ago.
This rise in temperature has caused the air over the Atlantic to become unusually warm and humid.
When the currents of this warm air met the currents of the dry and cold arctic air, a snow cyclone was formed - exactly what is needed for a strong blizzard.
Similar extreme winter weather conditions can be expected on the East Coast of the United States for many years, because both factors causing snow cataclysms will continue to operate: the Atlantic Ocean will continue to generate warm humid air currents in winter, and from the Arctic to the south cold and dry air will continue to flow.
“Perhaps in about 30 years, for short periods of time at the height of summer, the ice in the Arctic will completely melt, but in winter most of it will still freeze through,” says Kevin Trenbert, employee of the National Center for Atmospheric Research in the American city of Boulder, Colorado. … "This means that cold continental air will still form there."
However, climate change is by no means an unambiguous phenomenon. Even if global warming creates conditions for heavy snowfall in some regions, this does not mean that more snow will fall in the world as a whole.
"Extreme snowfalls are linked to climate change in a very different way than normal seasonal snowfall," explains MIT researcher Paul O'Gorman.
In a 2014 study, O'Gorman used computer models to investigate how normal and extreme snowfalls in the Northern Hemisphere could change by the end of the century, provided greenhouse gas emissions remain high.
He found that in regions less than 1,000 meters above sea level, where winter temperatures now drop slightly below freezing, the likelihood of extreme snowfalls would be reduced by only 8%.
However, the total amount of snow that falls in these regions during the winter can decrease by an average of 65%.
“In some regions, total seasonal snowfall is expected to decline, with little or even greater snowfall under extreme conditions,” O'Gorman said.
In the future, the snow season itself may become shorter. It is likely that the beginning and end of winter will be warmer throughout the Northern Hemisphere, so, according to Trenbert, precipitation during this period will fall as rain, not snow.
In other words, snowfalls in the future may indeed become less, and the "snow season" may also become shorter, but snow cataclysms in general will occur no less frequently than now.
This is bad news for the ski industry. “Many ski resorts on the [US] East Coast could be left without tourists due to irregular snowfall unless they find some alternative ways to attract visitors,” Trenbert notes.