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It’s a common question. So last winter, as another intense snowstorm blanketed a large part of the United States, we put it to Kevin Reed, an associate professor at the School of Marine and Atmospheric Sciences at Stony Brook University on Long Island.
It is true, he said, that in a warming world, less snow is falling overall, and covering less area.
But higher temperatures also allow the atmosphere to hold more water, which creates more precipitation and makes it more likely to fall quickly.
“That means there are still times and cases where that precipitation increase comes in the form of snow,” Dr. Reed said. “We know that to be true.”
Summers have always been more humid than winters because warmer air absorbs more moisture. As the moisture condenses, warm air rises faster, bringing even more moisture in a feedback loop that can create sudden, fast-falling downpours like the ones that spurred deadly floods in New York and New Jersey in the aftermath of Hurricane Ida last year.
Overall, Dr. Reed said, a few degrees of global warming means that some storms that would have brought snow on a 31-degree day will end up as rain at 33 degrees. But on the other hand, more snow falls when temperatures are just below freezing than during extreme cold.
“So a storm that’s a little warmer but still below freezing, a storm that might’ve been a 25-degree storm but ends up as a 30-degree storm, means it will snow more,” he said.
Flash floods are generally more likely during warm-weather downpours. But freezing temperatures bring their own flooding risks, Dr. Reed said: Ice can block drainage systems, and if rain or warmer temperatures follow snow, the melting can cause flooding.
“That’s the worst-case scenario when we’re right around the freezing line: Rain and snow melt and blockages all at once,” he said.
How Climate Change Can Supercharge Snowstorms
If the globe is warming, shouldn’t there be less snow?It’s a common question. So last winter, as another intense snowstorm blanketed a large part of the United States, we put it to Kevin Reed, an associate professor at the School of Marine and Atmospheric Sciences at Stony Brook University on Long Island.
It is true, he said, that in a warming world, less snow is falling overall, and covering less area.
But higher temperatures also allow the atmosphere to hold more water, which creates more precipitation and makes it more likely to fall quickly.
“That means there are still times and cases where that precipitation increase comes in the form of snow,” Dr. Reed said. “We know that to be true.”
Summers have always been more humid than winters because warmer air absorbs more moisture. As the moisture condenses, warm air rises faster, bringing even more moisture in a feedback loop that can create sudden, fast-falling downpours like the ones that spurred deadly floods in New York and New Jersey in the aftermath of Hurricane Ida last year.
Overall, Dr. Reed said, a few degrees of global warming means that some storms that would have brought snow on a 31-degree day will end up as rain at 33 degrees. But on the other hand, more snow falls when temperatures are just below freezing than during extreme cold.
“So a storm that’s a little warmer but still below freezing, a storm that might’ve been a 25-degree storm but ends up as a 30-degree storm, means it will snow more,” he said.
Flash floods are generally more likely during warm-weather downpours. But freezing temperatures bring their own flooding risks, Dr. Reed said: Ice can block drainage systems, and if rain or warmer temperatures follow snow, the melting can cause flooding.
“That’s the worst-case scenario when we’re right around the freezing line: Rain and snow melt and blockages all at once,” he said.
A Guide to Winter Weather
A white Christmas may seem magical, but be careful during a winter storm.
- A winter storm is tearing through much of the United States. Here’s what you can do if your holiday travel plans are disrupted.
- This may be one of the coldest Christmases for parts of the United States in recent years. Follow these steps to keep your home warm.
- To get through extreme winter weather, you need to be prepared. These essential tools can help you ride out a storm.
- Winter weather can create brutal driving conditions. Here are a few tips on how to drive safely in the cold and snow.
- What should you do if you’re trapped in your car during a snowstorm? Experts offer advice on how to keep warm and collected.
- To walk safely in the snow, turn your feet slightly outward and take short, flat-footed steps. Basically, walk like a penguin.
), and may actually be decreasing (
). The yearly ozone hole should continue for a while, though, as CFCs and other ODSs can last for decades in the air. Scientists found in a 2009 study that 