where is the snow The Great Lakes ice sheet is almost non-existent and reaches its lowest level in 50 years

(CNN) — A warm start to the winter season has left the Great Lakes virtually ice-free and with its lowest year-on-year snow cover in at least 50 years.

On New Year’s Day, only 0.35% of the Great Lakes were covered by ice, the lowest level for the date, and well below the historical average of about 10% for this point in winter, according to data from the National Oceanic and Atmospheric Administration (NOAA). Great Lakes Environmental Research Laboratory (GLERL).

The lack of snow on the Great Lakes this year adds to a growing trend of winter ailments in the US, from declining snowpack in the West to an ongoing snow drought in the Northeast, all increasingly common due to rising temperatures. climate crisis.

Since records began to be kept in 1973, researchers have found that the Great Lakes are experiencing massive ice loss, with peak coverage declining by about 5% per decade.

“It’s definitely very low for this time of year,” James Kessler, a physical scientist at NOAA’s GLERL, told CNN.

Air temperature is important when it comes to ice cover on the Great Lakes, Kessler said. Cold air is needed to cool water and freeze lakes. But with the climate warming rapidly, records show that warmer-than-average temperatures in the region are melting the chances of ice formation on the Great Lakes.

“We’ve had consistently above-average air temperatures in the region and we haven’t had consistently cold days,” Kessler said. “That’s what you really want,” Kessler said. “You need a consistent number of less than freezing days.”

Average temperatures in December in the upper Midwestern states around the Great Lakes were between -13 and -11 degrees Celsius above normal for the month. It was the warmest December on record for several cities along the Great Lakes, including Chicago, Detroit, Green Bay, Wisconsin, and Duluth, Minnesota.

It was the same story on the east side of the lakes, even with Cleveland; Erie, Pennsylvania; and Buffalo, New York; They experienced the warmest December on record. As a result, Lake Erie is currently completely ice-free.

It is a constant trend. According to Kessler, Lake Erie has experienced an ice cover loss of about 5% per decade, while Lake Superior is experiencing the fastest rate of ice cover loss at about 7% every 10 years. Recent studies have shown that Lake Superior is one of the fastest warming lakes in the world, due to planet-warming pollution.

It’s still early in the season, Kessler cautioned. Prolonged bursts of Arctic air in the coming weeks could lead to a rapid increase in snow coverage. And peak snow on the Great Lakes usually occurs in late February or early March.

While there is year-to-year variability, the Great Lakes are trending toward a future with less ice cover, Kessler said.

“First of all, (the data) is very noisy,” Kessler said. “But if you fit a trend line to this data, you get a decreasing trend, so we see that (ice cover) is decreasing.”

Low ice cover on the Great Lakes has serious consequences for industry and the environment.

Less snow can extend the shipping season. Water shipping along the Great Lakes could increase as ice-free waters make way for more ships, according to researchers at the University of Wisconsin-Superior, who are analyzing how shrinking ice cover could directly affect navigation there.

“The commercial shipping industry is like a multibillion-dollar industry, so less ice cover is good for them,” Kessler said. Kessler said, “The US has to go save them and that’s a huge task. So from that perspective, less ice is better economically.”

On the other hand, he said, there are also economic benefits when lakes freeze: coastal cities benefit through recreational activities such as ice fishing competitions or ice hockey games.

Lake Michigan

A pair of surfers take advantage of mild temperatures while exploring conditions around Lake Michigan on December 28, 2023 in St. Joseph, Michigan. (Credit: Don Campbell/The Herald-Palladium/AP)

Snow cover also protects the shores of lakes. Without it, high waves can cause severe flooding, coastal erosion and damage. The lack of ice coverage could lead to more severe blizzards like the one that paralyzed Buffalo, New York and surrounding cities in 2022, Kessler said.

When very cold, windy conditions occur on a non-frozen lake, the stage is set for “lake effect” snow. And the Great Lakes are the only place in the United States where this phenomenon occurs, except occasionally in Utah’s Great Salt Lake.

Kessler said that while the first few days of January have been notable for low ice cover on the Great Lakes, daily lows are not as significant as monthly lows.

“If January as a whole is less average than the previous January, that will be more noticeable to me,” he said.

It’s impossible to know exactly how temperatures will play out over the rest of the winter in the Great Lakes. But a strong El NiƱo winter like this year usually means warmer-than-average temperatures there, meaning it can be an uphill battle for lake ice.

— CNN meteorologist Brandon Miller contributed to this report.

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