Greenland Losing Resilience to Melt
Changes to the structure of Greenland’s ice sheet may have altered its ability to store water, meaning more water may be draining into the oceans than scientists had previously calculated, reports the Washington Post.
The new study, published in the journal Nature Climate Change, focuses on a layer of the ice sheet called firn. Firn is compacted snow – it’s not as dense as glacier ice and it forms a porous layer near the surface of the ice sheet. It traps and stores water before it can run off the glacier and into the ocean, mitigating sea-level rise.
William Colgan, a professor from York University in Toronto, Canada, and coauthor of the study, spent five weeks in Greenland in 2013 drilling firn cores. The team was interested in how the physical structure of the firn layer had changed as temperatures warmed. He also helped analyze the data from three expeditions there in 2012, 2013 and 2015.
In 2012, extreme levels of melting occurred across most of the ice sheet, which later formed a layer of solid ice several meters thick on top of the porous firn in low elevation areas. “In subsequent years, meltwater couldn’t penetrate vertically through the solid ice layer, and instead drained along the ice sheet surface toward the ocean,” Colgan said in a press release. The firn no longer acted as a sponge, absorbing meltwater and limiting the loss of the ice sheet.
Scientists are carefully watching Greenland’s ice sheet because of the enormous volume of frozen water it holds – and its potential to raise sea levels. Scientists say it has lost more than 9 trillion tons of ice in the past century and that it is losing about 287 billion tons of ice annually. The computer models scientists use to understand Greenland’s contribution to sea-level rise do not take changes to the firn layer into consideration, meaning its contribution to sea-level rise is likely higher than predicted.
Ocean Protection Must Balance Inuit Needs
The portion of Canada’s marine environment under protection is expected to grow several times over in the next 15 years. But environmental protection must be balanced with the needs of Inuit communities, reports CBC News.
Inuit communities have traditionally fished and hunted marine mammals along Canada’s northern coasts, and many of its residents still do. They want assurances that they can carry on with these practices – and that the environmental protections put in place will safeguard their longevity.
Canada has a vast ocean territory, of which only 1.3 percent is protected. But that is expected to change quickly in order for Canada to meet its target of protecting 10 percent of its oceans by 2020. It has been more than five years since the federal government assigned Canada’s waters to environmental protection, according to a December article in the Globe and Mail.
The Arctic Council is studying marine protected areas throughout the region with the goal of creating a network linking the marine protected areas of Arctic nations. Lancaster Sound in Canada’s eastern Arctic is one of the locations in need of protection, according to WWF-Canada.
Climate Change Puts Power Plants at Risk
Power plants rely on freshwater from rivers and streams to cool their operations. But warming water and decreases in its availability, due to climate change, could lead to reductions in electricity production in 60 percent of power plants worldwide, according to a new study published in the journal Nature Climate Change.
The study looked at 1,400 traditional power plants and about 25,000 hydropower systems globally, Carbon Brief reported. Traditional power plants in Alaska, Iceland and parts of Scandinavia are expected to see drops of up to 15 percent of their power output by 2050 if greenhouse gas emissions remain high. Hydroelectric power plants in the Arctic region are more variably affected, according to the study, with some seeing decreases in power plant capacity and others seeing increases.
Water turns the turbines and generates electricity at hydropower plants; it is also used for cooling at power plants that generate electricity from nuclear reactors or by burning fossil fuels and biomass. The demand for water to generate electricity is expected to double, according to the study.
- The New York Times: Closing the Farm-to-Table Gap in Alaska
- Eos: Vanishing Sea Ice Could Trigger More Arctic Precipitation
Top image: Rivers of meltwater form on the Greenland ice sheet and flow toward the sea. (Geological Survey of Denmark and Greenland/Dirk van As)