Image of the snow cover on the Great Lakes caught on February 13, 2023, by the NOAA-20 satellites Visible Infrared Imaging Radiometer Suite (VIIRS).
This winter, ice cover in the Great Lakes Basin has hovered at unusually low levels.
The Great Lakes have been unusually ice-free so far this winter season. In truth, since February 14, 2023, ice covered only 6.6 percent of the 5 freshwater lakes. This is substantially less than the 35-40 percent ice cover that is typical for mid-February, according to data released by the National Oceanic and Atmospheric Administrations (NOAA) Great Lakes Environmental Research Laboratory (GLERL).
When the Visible Infrared Imaging Radiometer Suite (VIIRS) on the NOAA-20 satellite got this image on February 13, ice cover on the lakes was 7 percent. A strip of ice can be seen crossing Lake Hurons Saginaw Bay.
1973– 2023
Air temperature levels are the primary factor affecting ice cover on the Great Lakes. According to the U.S. National Ice Center, each of the 5 lakes experienced warmer than typical air temperatures in January 2023. The typical temperature across the adjoining U.S. was 35.2 degrees Fahrenheit (5.1 degrees above average) according to NOAA, making January 2023 the sixth-warmest January on record.
Ice extent throughout the Great Lakes Basin briefly leapt to 21 percent in early February in reaction to a cold snap. However ever since, it has actually declined through a minimum of mid-February. Optimum ice cover usually occurs between early and mid-february March.
Ice cover on the lakes varies from year to year. An analysis led by Jia Wang, an ice climatologist at NOAAs GLERL, reveals a downward pattern covering 44 years. During the winter period, which runs from December 1 to April 30, average ice cover on the Great Lakes decreased 69 percent between 1973 and 2017.
Anthropogenic warming has actually contributed in this decades-long decrease. A larger aspect, Wang has discovered, is the natural patterns of environment irregularity over the Pacific and Atlantic oceans: the North Atlantic Oscillation, the Atlantic Multidecadal Oscillation, the Pacific Decadal Oscillation, and the El Niño-Southern Oscillation.
” Each year we need to take a look at these four patterns to design ice cover,” stated Wang. “Right now, the Pacific Decadal Oscillation together with the North Atlantic Oscillation are causing warming in the Great Lakes.”
NASA Earth Observatory images by Joshua Stevens, utilizing VIIRS data from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System (JPSS) and lake ice information from NOAA– Great Lakes Environmental Research Laboratory.
As of February 14, 2023, ice covered only 6.6 percent of the 5 freshwater lakes. When the Visible Infrared Imaging Radiometer Suite (VIIRS) on the NOAA-20 satellite obtained this image on February 13, ice cover on the lakes was 7 percent. Air temperature levels are the main factor impacting ice cover on the Great Lakes. Throughout the winter season period, which runs from December 1 to April 30, average ice cover on the Great Lakes decreased 69 percent between 1973 and 2017.
