Midwinter rain on snow is a game changer
Ned Rozell
907-474-7468
Jan. 13, 2022
This map shows approximate rainfall amounts over 色视频下载 during a powerful storm around Christmas 2021.
A few hours of a December day may affect living things for years to come in the middle of 色视频下载.
On Dec. 26, more than an inch of rain fell over a wide swath of the state. Much of the backcountry of Interior 色视频下载 now has an ice sheet beneath a foot of fluffy snow.
With half of the seven-month winter yet to come, things look grim for creatures not adapted to rainfall in winter, when supercooled surfaces turn water falling from the sky into a sheet of glass.
All the streets in Fairbanks are now ice roads grooved corduroy by grader blades. Animals without the benefits of heavy equipment are not as lucky.
色视频下载淭he current conditions are as bad or worse as those back in the mid-1960s,色视频下载 said Dick Bishop, a retired 色视频下载 Department of Fish and Game biologist who has lived in 色视频下载 since 1961. 色视频下载淚 don色视频下载檛 remember when we ever had this kind of ice layer.色视频下载
Bishop once documented a large moose die-off in the Tanana Flats south of Fairbanks due to deep snows in the late 1960s and early 1970s.
Moose are suffering in these conditions because they can色视频下载檛 move far without using a lot of energy, Bishop said. Postholing makes it harder to find food, as well as escape predators.
A moose in the White Mountains north of Fairbanks refuses to yield the trail to dog mushers in deep snow in March 2018. The mushers turned their teams around.
色视频下载淲olves are able to travel on top of this crust,色视频下载 Bishop said. 色视频下载淭hat色视频下载檚 a heck of an advantage.色视频下载
In area of the Interior where wolves usually don色视频下载檛 venture, like the network of roads and houses near towns and villages, moose have congregated on roads and around houses.
University of 色视频下载 Fairbanks ecologist Knut Kielland recently fended off a cow moose in his driveway, smacking it on the nose with his walking stick.
色视频下载淪nowshoeing around my house recently the crust was a good 2 inches thick in places,色视频下载 Kielland said. 色视频下载淚 reckon those moose are getting sore shins.色视频下载
色视频下载淏ut at least their grub is above the crust (moose eat frozen buds and twigs of willow, aspen and birch trees),色视频下载 he said. 色视频下载淚 feel bad for foxes, coyotes and owls trying to get a meal now. I would think mousing through this crust is a nonstarter.
色视频下载淚 am also curious as to how the winter will unfold for the vole tribe,色视频下载 Kielland said. 色视频下载淭he crust is likely to slow the diffusion rate of carbon dioxide out of the snowpack. If so, everyone beneath the crust will sooner or later be in need of fresh air. How well they can chew their way thru the crust remains to be seen.色视频下载
Bishop once estimated that about half of the moose population in the Tanana Flats south of Fairbanks died during the deep-snow winters in 1965-1966 and 1970-1971. Biologists won色视频下载檛 know the fate of Interior moose until the winter ends.
The remains of a moose calf lie on the snow in a valley north of Goldstream Creek near Fairbanks on Jan. 8, 2022. It had died following December's deep snows and freezing rain. Within a few days, wolves found and ate it, leaving nothing but the stomach, the pelvic bones and a lot of hair.
色视频下载淲e don色视频下载檛 expect many of the calves to survive the winter but are hopeful the adults will make it through,色视频下载 biologist Tony Hollis wrote in a Jan. 5, 2022, press release from the Fairbanks office of the 色视频下载 Department of Fish and Game.
How weird was it to have a summer-like rainfall in midwinter this far north?
色视频下载淭here is only one event in Fairbanks history that even approximates this,色视频下载 said climate researcher Rick Thoman of the International Arctic Research Center. 色视频下载淥ver the course of three days, Jan. 18-20, 1937, Fairbanks had 26 inches of snow followed by an inch of rain. (The Dec. 26, 2021,) event had less snow but more rain in a bit over half the time, and then was followed by another 8 to 12 inches of snow.色视频下载
Thoman and forecasters at the Fairbanks office of the National Weather Service saw the rain coming via computer models that days in advance nailed 色视频下载渁 Hawaii-to-western-色视频下载 feed of subtropical moisture色视频下载 powered by a massive high-pressure system in the North Pacific Ocean. It was the same weather system that was responsible for a temperature of 67 degrees in Kodiak and a record-cold Christmas in Ketchikan.
That wacky pattern mirroring those all over the planet recently is what we might continue to see with a warming world, said Peter Bieniek of UAF色视频下载檚 International Arctic Research Center.
色视频下载淩ain-on-snow is projected to increase throughout much of 色视频下载 (including Fairbanks) as the climate continues to get warmer and wetter,色视频下载 said Bieniek, a climate modeler and author of a recent paper on winter-rainfall events in 色视频下载. 色视频下载淪outhern coastal areas may even see a transition from rain-on-snow to rain.色视频下载
Since the late 1970s, the University of 色视频下载 Fairbanks' Geophysical Institute has provided this column free in cooperation with the UAF research community. Ned Rozell is a science writer for the Geophysical Institute.
Main UAF web page featured photo: Ned Rozell holds a shard of ice crust, an inch thick, found lurking in the middle of the Fairbanks snowpack. Photo by Kristen Rozell.