Arctic could see more rain than snow in 30 years, study suggests

There could be more rainfall than snow in the Arctic in as little as 30 years because of the world's changing climate, according to a new study that predicts the transition will happen decades earlier than previously anticipated.

The change is expected to happen sometime between 2050 and 2080, says research led by the University of Manitoba and published in the journal Nature Communications. Previously, the transition to a rain-dominated Arctic was expected to happen somewhere between 2070 and 2090. 

Lead author Michelle McCrystall, a postdoctoral fellow at the university's Centre for Earth Observation Science, said more than 50 per cent of precipitation in the Arctic falling as rain instead of snow will have "global implications" and a "very direct impact" on Indigenous people throughout the Arctic.

The biggest precipitation changes, she added, will happen during the fall. Predominant snowfall and snow precipitation is still expected in the winter months, even by the end of the century.

Some regions will make the transition earlier than others, she explained, based on their temperatures and proximity to the North Pole. 

The study's projections stem from an aggregation of data from around the world. 

McCrystall said the 2050 to 2080 range in which the transition could happen reflects the variability of all the data that was used, but the average points to it happening, more specifically, around the year 2070. 

McCrystall said more rain in the Arctic would also lead to more rain-on-snow events — when rain falls onto an existing snowpack and freezes, forming ice layers either on the snow or within it — which would be "very damaging" for foraging mammals like reindeer, caribou and muskox. 

Because of that ice, foraging animals will have a harder time reaching the grassland that lies beneath it. 

"It can cause a huge starvation and die off in a lot of these populations," she said.

Mark Serreze, a co-author of the study and the director of the National Snow and Ice Data Center in Boulder, Colo., said in a statement "the Arctic is changing so fast that Arctic wildlife might not be able to adapt.

"It's not just a problem for the reindeer, caribou and muskox, but for the people of the North that depend on them as well."

Kent Moore, a professor of atmospheric physics at the University of Toronto, who is outside of the research team, told CBC News that rain-on-snow events would also cause "incredible" stress on hairy animals like muskox. 

"If it rains and then it freezes, then they get a kind of frozen ice on their body, and that can be very, very stressful for them. They can lose heat more rapidly."