As the highest peak in the northeastern United States, the weather on the top of Mount Washington can change in a second.
From on high, forecasters and researchers at the Mount Washington Observatory are tracking all of these changes, collecting data and studying what trends over time indicate about the changing climate.
In an annual presentation this week, researchers from the summit shared findings from two research projects conducted this year about how much precipitation is falling on snow and how the temperature changes at various altitudes along the mountain.
Here’s what they found:
Karl Philippoff is a weather observer and research specialist, who’s been studying temperature at different altitudes in the air right above the surface of Mount Washington at a range of elevations. He wanted to see how they change on a daily, monthly, and yearly basis.
Typically it gets colder as elevation increases, a phenomenon many people have experienced when ascending a mountain. But Philippoff was able to use real data from stations placed every 1,000 feet or so along the Mount Washington Auto Road, rather than depend on a general estimate of how altitude typically affects temperature.
He looked at data from 2016 to 2022, and found that lower stations have a much greater range in temperature, while the summit temperature tended to vary less widely.
This research is directly relevant to humans, and also to glaciers or snowpack.
“Especially for snow hydrology and glaciers, those surfaces are where that energy exchange is happening, and so that’s where they’re melting,” Philippoff said during the presentation.
Jay Broccolo, the director of weather operations at the observatory, said the intent of the project was to see if the way temperature changes near the earth’s surface is different from how it changes higher in the atmosphere. “Lots of places report that,” he said, but this research was able to actually prove it with “excellent” quality data.
One application is for ski resorts looking to make snow. “It would be really useful for ski resorts and snowmaking,” Broccolo said. In certain conditions, he said, “it’s really hard for them to make snow.” Often, he said, weather conditions mean the machines inadvertently end up making ice rather than snow, an outcome no one is pleased with.
A second research project focused on how much precipitation fell on snow during a 40-year period from 1980 through 2020.
Myah Rather is a graduate student at Howard University who analyzed the observatory’s data on precipitation over that time period. Rather wanted to learn if Mount Washington’s weather extremes were getting more intense at the same time they’re becoming less predictable.
She found that the snow depth on the summit has been growing over time. “Seeing the accumulation of 30 inches to nearly 35 inches of snow depth was really crazy to me,” she said.
Rather was only able to study how much precipitation fell on the snow. In the future, the observatory will parse the data to understand which kind of precipitation is falling when, so they can answer questions about how much rain is falling on the snow, a pressing topic as temperatures are warming.
Rain falling on the snow can have a big impact on the ecosystem.
“One of the threats of heavy rain on a lot of snow, there’s a lot of frozen liquid in this case that’s locked up in those snowpacks, and certainly, the river forecast centers around here in the region are looking out for flood threats,” said Brian Fitzgerald, the Observatory’s director of education.