Are winters getting less snowy?
Clip: Season 51 | 4m 49s | Video has closed captioning.
Winters are getting warmer and they’re also getting shorter. So we’re getting less snow ... right?
Aired: 05/03/24
Problems Playing Video? | Closed Captioning
Clip: Season 51 | 4m 49s | Video has closed captioning.
Winters are getting warmer and they’re also getting shorter. So we’re getting less snow ... right?
Aired: 05/03/24
Problems Playing Video? | Closed Captioning
- When I was a kid, I cherished snowy winters filled with sledding and snow forts.
Recent winters, however, have started to seem distinctly less snowy.
I live in New England, a region known for its blizzards, but I can't remember the last time I stepped out into the winter wonderland I remember from my childhood, and I'm not the only one who's noticed this.
Are winters truly becoming less snowy?
Well, winters are getting warmer and they're also getting shorter by nearly two weeks since 1972.
So we're getting less snow, right?
Not quite.
These are annual snowfall totals from my hometown of Boston going back to 1970.
If my memory is accurate, there should be a clear downward trend, but there isn't.
There is no correlation negative or positive between snowfall and time.
How could this be?
How is snowfall staying the same while temperatures increase?
- You can get warmer and we have, and it can still snow a lot because the temperature still remains below freezing and it's just less below freezing - Snowfall is responding not just to temperature, it's also responding to how much moisture is available.
- It turns out that warmer temperatures have varied effects on snowfall rates.
Some areas of Alaska, the fastest warming US state, have seen record smashing roof crushing amounts of snow this year, while in parts of the southwest, southeast, and midwest, snowfall has been in steep decline.
In Boston, the impact of rising temperatures can be counterintuitive.
One reason is that hotter air can hold warm moisture, which will fall as snow when it's cold enough and rain when it's not.
This also means that winter storms when they occur, may actually bring more snow than they used to.
- It's been found that more of our precipitation is falling in large events.
Not necessarily that we're getting more, but when it rains, it pours is essentially what it looks like.
- This could explain the anomalous winter season in Anchorage, Alaska.
The 49th state is getting warmer and warmer, but it's still cold enough to snow.
Today is Christmas.
It is nearly 50 degrees Fahrenheit in Boston, and I'm uncomfortable in my thick winter coat.
I've barely seen a single snowflake this entire fall, and having lived here my whole life, this just feels weird.
But there is another measurement of snow that may have some answers.
The number of days each winter with snow on the ground or snow covered days.
This graph shows snow covered days in Boston going back to 1997, and although it may not look like there's a trend here, there is.
The correlation between time and snow covered days is negative and statistically significant, which means that even though total snowfall may not be decreasing, it is melting faster and Bostonians are experiencing increasingly bare winters.
- You can have less time with snow cover and just as much snow.
Snowfall versus cover can tell different stories.
- So what is happening to snowing in the US?
In some parts of the country, snowfall is decreasing.
In others, it is increasing.
And in some, it is staying about the same despite the fact that overall temperatures are rising.
Snow cover days paint a more consistent picture across the US too.
Since 1972, they have decreased in the US by an average of nearly two weeks, and the extent of snow coverage across North America is shrinking as well.
In the end, the data does corroborate my memories.
The northeast, like many other parts of the US, truly is getting less snowy and personally, that disappoints me.
For some, however, increasing temperatures may not be a bad thing.
They do, after all, mean less snow shoveling and lower heating bills, whether you like white winters or not, major changes are in store for our ecosystem.
- The snow itself is a habitat.
There's this space between the snow pack and the soil.
This space is an important habitat for lots of organisms, especially arthropods and insects.
When we lose snow cover, we lose that habitat.
- Warmer conditions could also allow certain insects, including Lyme disease carrying ticks to live in places that were previously too cold for them.
- As we lose cold temperatures, we lose the killing temperatures that keep these insects at bay.
We can see more mosquitoes that carry diseases like Eastern equine encephalitis and West Nile virus.
- No matter where you live, weather patterns seem to be changing across the US.
From drastic temperature swings, intense storms, flooding and wildfires, this season looks different from years past.
- Our winters are changing really fast and so we're witnessing these phenomenon in real time and it's not clear who the winners and losers are in this new warmer winter world.
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