It’s just before noon on a late April morning. Much of Southcentral Alaska grumbles beneath a crusty veneer of yet another late-season snowfall obliterating the promise of an early spring.
At least it’s not 15 below, with gusts up to 10 mph.
That was the weather Tuesday at 14,200 feet on the frigid flanks of Denali, according to data now available with the click of a mouse from North America’s tallest peak thanks to a combination of high-elevation technology and old-fashioned mountaineering skills.
Three new weather towers installed last year are expected to provide crucial data for climbers, search and rescue operations, and the pilots who make regular flightseeing trips over the area when they’re not ferrying mountaineers in and out.
They’re also designed to provide a rare glimpse into high-elevation snowpack for scientists trying to gauge the status of more than 7,000 glaciers in Alaska’s national parks.
A team of National Park Service climbing rangers and scientists installed the weather towers on Kahiltna Glacier last climbing season.
The stations are finishing a first full year of data collection as the 2019 climbing season gets underway. Rangers will help maintain them during regular patrols to camps on Kahiltna.
Talkeetna, the funky hamlet at the foot of Denali, is filling with mountaineers coming to town for Alaska Range trips. The Denali climbing season won’t kick off in earnest for another week or two, though four climbers in two groups were making an attempt at the popular West Buttress route this week.
The teams arriving in Talkeetna now will benefit from the new stations providing real-time information online for the 20,310-foot peak that makes its own weather, rangers say.
Data from the sites will also help National Weather Service forecasters in Fairbanks “ground truth” a recreational climbing forecast they produce for the mountain from late April through mid-July, said Denali National Park and Preserve south district ranger Tucker Chenoweth.
“That then also leads to better decision-making on the ground for the climbers,” Chenoweth said.
It took a day each to install the stations, Chenoweth said. He climbed using Prusik knots and ropes to ascend and installed equipment while suspended from the tower.
All three stations collect hourly measurements of air temperature, snow accumulation and melt, according to the “Denali Dispatches” blog. The 14,000-foot camp and base camp stations also measure wind speed/direction and incoming/reflected solar radiation. The latter two stations are additionally equipped with telemetry equipment that allows rangers, forecasters and the public to view real-time measurements online.
NPS glaciologist Michael Loso initiated the weather station project with Chenoweth “because I had a strong interest in figuring out what is happening at the higher elevations of Denali.”
The Kahiltna is the one Denali glacier that Loso studies as part of his job monitoring glaciers in national parks.
Kahiltna, like nearly all of Alaska’s glaciers facing warmer summers and a longer melting season, is shrinking, Loso said. But it’s possible that the Denali glacier is unusual: It may be snowing more at high elevations than it used to, though less at 14,000 feet than 10,000 due to the colder air’s inability to “hold” precipitation.
Normally, glacier research relies on measuring snowpack at the end of winter and beginning of fall, using long metal poles. But that assumes there’s less snow in summer when melting occurs, Loso said. Scientists think that Denali actually sees more snow in summer than winter.
“We think that’s true at 14,000 and we will have data -- soon -- to confirm that," he said.
Along with weather gauges, the towers are fitted with devices that measure snowpack throughout the year via nearly inaudible clicks beamed down to the surface and back.
Understanding how glaciers are changing is vital in Alaska, given the role they play in everything from roads and rivers to salmon, wildlife and recreation, Loso said.
“Changes in glaciers are not just incidental,” he said. “When you look at them collectively, you’re looking at impacts that are really substantial.”