When the United States purchased Alaska from Russia, Americans considered the “frozen wasteland” to be a reckless, wasteful acquisition. What could ice possibly offer?
In fact, polar ice is a critical resource for the Earth. The summer and fall of 2020 marked the lowest sea ice extent ever recorded in the Arctic Ocean, and the Intergovernmental Panel on Climate Change (IPCC) says contemporary September sea ice extents are so low that they are unprecedented in at least 1,000 years. Moreover, collapses in the ice shelves of West Antarctica, Canada, and Greenland expressed mounting concerns in 2020. The immediate effects of climate change in the polar regions are merely the tip of the iceberg—ultimately, they have profound effects on climate and communities around the world.
Sea level rise
Globally, current annual mean rates of sea level rise is a few millimeters per year. But the rate of sea level rise is accelerating, and the Greenland Ice Sheet is the largest source of new sea water. Emissions at current levels could cause further Greenland and Antarctic ice sheet melt, leading to more than 15 inches of global sea level rise by 2100, increasing storm surges, flooding, and infrastructure costs along coastlines around the world.
In 2020, the accelerated fracturing of West Antarctica’s Thwaites and Pine Island Glaciers caused alarm for researchers, in part due to hydrofracturing, a process through which meltwater greatly exacerbates the breakage of ice by seeping into and placing pressure on crevasses and already-splintering areas. Thwaites Glacier will likely be a major contributor to sea level rise in the future, and its continued retreat could trigger a positive feedback loop of cascading collapse, fracturing the entire West Antarctic Ice Sheet. Currently, melting from the Thwaites and Pine Island Glaciers contributes around 5 percent of global sea level rise.
Glacier collapses across the Arctic further illustrate the positive feedback loop that happens as glaciers begin to melt. In July 2020, the Milne Ice Shelf—Canada’s last fully intact ice shelf—lost more than 40 percent of its area in two days as it disintegrated and drifted away after decades of incremental ice loss. Nioghalvfjerdsfjorden Glacier (79N Glacier) in Greenland, the Arctic’s largest remaining floating ice shelf, has demonstrated extraordinary signs of collapse, continued major ice loss, and the recent disintegration of Spalte Glacier—79N’s northern tributary—in the northeast part of Greenland.
Because seawater has a higher pH than freshwater, reduced sea ice and collapsing ice sheets lower the pH of the global ocean. Moreover, colder waters like the Arctic Ocean uptake more CO2 than warmer waters. (Consider a glass of sparkling water: a glass with ice stays bubbly with CO2 longer than one that’s room temperature.) Together, these effects lead to a process called ocean acidification that is already impacting fisheries around the world.
The Arctic Monitoring and Assessment Programme estimates that over 80 percent of northeast Arctic cod stocks could be eliminated by continued warming and acidification, greatly increasing the risk of fishery collapse. The value of a sustainable catch would fall from 2.3 billion Norwegian kroner (USD$285 million) to just 300 million kroner (USD$36 million) by 2100. Changes in seasonal sea ice alters marine primary production and ecosystems around the Arctic, and ocean acidification slows growth rates and reef accretion in more tropical regions. An increasingly acidic ocean will certainly affect markets, like those for mollusks and other animals with shells.
The ocean’s removal of greenhouse gases from the atmosphere has significantly mitigated the rate of climate change. But as the polar oceans warm, they will be less effective as carbon sinks. And already, the Southern Ocean accounts for more global ocean heat gain than is proportional to the area it covers.
Polar warming amplifies global warming
Snow and ice have high albedos, cooling the planet by reflecting the sun’s rays back to the atmosphere as short-wave radiation. In the Arctic and Antarctic, the snow and ice albedo effect generates a positive feedback loop with extreme impacts when temperatures rise: as ice disappears, more energy from the sun is absorbed by the land or water and emitted as heat, further limiting the growth of ice. This is one reason scientists agree that recent ice sheet losses could be irreversible over decades to millennia, with far-reaching repercussions beyond the poles.
Moreover, carbon-rich, frozen ground called permafrost has reached record high temperatures at many long-term monitoring sites in the circumpolar North. As permafrost melts, the ensuing release of carbon dioxide and methane have the potential to accelerate global warming.
Lessons from the Arctic
While the rest of the planet depends on the Arctic environment, the Arctic environment also depends on the rest of the planet. The IPCC suggests that the difference between a 1 percent chance of an ice-free December 2100 and 10-35 percent chance of an ice-free December 2100 comes down to the limiting global temperature rise to 1.5°C versus 2°C.
The global temperature has already risen over 1°C, and it is imperative that countries find new ways to minimize their greenhouse gas emissions. Arctic communities like Newtok, Alaska—whose residents have been displaced and many encouraged to move due to permafrost melt—are confronted with the life-altering effects of climate change. Coastal erosion, permafrost melt, and flooding has destroyed homes, land, and critical infrastructure.
Indigenous communities on the front lines of Arctic warming, like Newtok, are some of the first to understand the dramatic effects of climate change. Their tightly coupled relationship with the environment goes back millennia, and offers a wealth of knowledge about environmental stewardship. This relationship provides opportunities to better understand climate change, its impacts and what adaptation entails. Meaningful engagement with Arctic peoples could improve the development and implementation of policymakers’ strategies for just climate adaptation and mitigation measures.
Michaela Stith is a Program Assistant for the Wilson Center’s Polar Institute.
Olivia Popp is a Staff Intern for the Wilson Center’s Polar Institute.
Sources: Arctic Council, Arctic Monitoring and Assessment Programme, BBC, British Antarctic Survey, ClimateWatch Magazine, Geological Survey of Denmark and Greenland, Intergovernmental Panel on Climate Change, Journal of Geophysical Research, Library of Congress, NASA, National Geographic, Natural Resources Defense Council, Proceedings of the National Academy of Sciences, PLOS ONE, Public Radio International, Scientific American, Smithsonian Institution, Washington Post, Yale
Photo Credit: Antarctic glacier melting, courtesy of Bernhard Staehli, Shutterstock.com
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