Wild weather in the Arctic causes problems
Top image: Reindeer on icy ground in Svalbard. Photo: Brage B. Hanssen/NTNU
In January 2012, the weather in Svalbard was hit by a weather event than only happens once every 500 years. The extreme weather caused problems both for the wildlife and the society, but it also sparked an interdisciplinary cooperation that has resulted in a scientific article published today.
20 November 2014
Via Science Daily/The Norwegian University of Science and Technology (NTNU):
Temperatures were ridiculously warm – and reached a maximum of nearly +8 degrees C in one location at a time when mean temperatures are normally -15 degrees C. It rained in record amounts.
Water and ice
Snow packs became so saturated that slushy snow avalanches from the mountains surrounding Longyearbyen covered roads and took out a major pedestrian bridge. Snowy streets and the tundra were transformed into icy, rain-covered skating rinks that were difficult to navigate with snowmobiles. Flights were cancelled, the airport closed, and travel around town was tricky.
The situation was particularly problematic out on the Arctic tundra. Rain falling on snow can percolate to the base of a snowpack where it can pool at the soil surface and subsequently freeze. That makes it impossible for grazing reindeer to get at their food, for example, and extreme warm spells can even affect temperatures in the permanently frozen ground found throughout the archipelago.
But the extreme event also offered an interdisciplinary group of scientists, from climatologists to biologists to snow geophysicists and structural engineers, a chance to document the event and learn from it. Their cross-disciplinary report, “Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic,” was published on 20 November 2014 in Environmental Research Letters.
– We had a unique opportunity to document what happened, and we did,” said Brage Bremset Hansen, the first author on the paper, and co-author Øystein Varpe.
– This was a case study from one event…but since it was an extreme event, and with all of our contacts in the different disciplines, we were able to compile this information into one story, which is quite rare, they said.
Brage Bremset Hansen is a biologist at the Norwegian University of Science and Technology’s Centre for Biodiversity Dynamics, and Øystein Varpe is an associate professor at the University Centre in Svalbard.
Reindeer mortality up
As a biologist, Hansen was very interested in how the extreme weather would affect the archipelago’s natural communities. Only four vertebrate species overwinter in Svalbard – the wild Svalbard reindeer (Rangifer tarandus platyrhynchus), the Svalbard rock ptarmigan (Lagopus muta hyperborea), and the sibling vole (Microtus levis), and one animal that eats them all, the Arctic fox (Vulpes lagopus).
When Hansen and his colleagues compared summer population counts of reindeer after the January 2012 event to counts conducted for the previous summer, they found that the number of reindeer carcasses in many populations was among the highest ever recorded.
Tourism and infrastructure
And for Svalbard residents, who are some of the most northerly inhabitants on the globe, there were significant socioeconomic effects. During and after the event, it was difficult for snowmobiles to travel out on the tundra on the thick layer of ice, Varpe said.
This thick layer, averaging 15.3 cm, persisted out on the tundra well after the event was over, said glaciologist Jack Kohler at the Norwegian Polar Institute.
– The winter rain event leads to the ground-ice formation, and the ice lasts the remainder of the melt season, until it melts, and that is what I would call the significant happening. The rain is an event, for sure, but the ice is actually the (big) event, Kohler said.
The result was a strong decrease in tourism for the rest of the winter, specifically for activities such as guided snowmobile and dogsled tours. Tour numbers dropped by 28 percent compared to the previous winter, and were the lowest ever since 2001, which is when statistics were first continuously kept. The researchers also believe that had a ripple effect on hotel stays and other tourist activities.
Read more about the researchers’ findings in this article from Science Daily: Wild Weather in the Arctic
Brage B. Hansen, Ketil Isaksen, Rasmus E. Benestad, Jack Kohler, Åshild Ø. Pedersen, Leif E. Loe, Stephen J. Coulson, Jan Otto Larsen, and Øystein Varpe: “Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic”. Environmental Research Letters, 20 November 2014.