The weather forecast says to expect a snowy morning commute, but can these predictions always be trusted? Jim Steenburgh, a U professor of atmospheric sciences, suggests they cannot.
Steenburgh researches the “lake-effect,” which refers to heightened rain or snowfall generated as a storm moves over a warm body of water, such as the Great Salt Lake. The collision of cold and warm air destabilizes the atmosphere and makes the lake-effect “very chaotic and hard to predict,” Steenburgh said.
His study examines the accuracy of computer models that make snowfall assessments, which Steenburgh says do not possess enough detail to properly simulate the effects of a storm. The research group struggled to accurately predict storm conditions even when more technologically advanced models were used to examine past events.
Despite the attention lake-effect snowfall receives in Utah, large lake-effect storms are rare and account for around five percent of the total winter precipitation in the Salt Lake Valley and the Wasatch Mountains. Utah occasionally receives up to two feet of snow from such storms, which creates a “huge need to better understand and predict these storms,” said Peter Veals, a graduate student in the Department of Atmospheric Sciences, in an emailed statement.
Steenburgh has also researched Lake Ontario, one of the five Great Lakes. The larger lake increases the accuracy of the storm predictions, Veals said. Lake Ontario’s lake-effect storms function differently than the Great Salt Lake’s, as the mountains are smaller but the lake is larger.
“The storms there are very intense,” Steenburgh said.
The research on Lake Ontario has undermined past scientific belief that storms get deeper and turbulence gets stronger as they progress. Instead, they get shallower as they move.
“The storms we’ve learned [about] don’t really work the way we thought,” Steenburgh said.
Veals primarily works with the research done on Lake Ontario and has found the form of the storms and wind speed “are strong predictors of whether the high terrain or the lowlands will see the most snowfall.”
In comparison with the Great Lakes, smaller lakes, such as the Great Salt Lake, have received little scientific attention. The work done by Steenburgh and his colleagues, both in Utah and in other parts of the world, has expanded the knowledge of lake-effect storms. His research will likely help improve the accuracy of forecasts, especially in Utah.
@sarahnlegg