Sea ice decline from 1979 - 2019. Visualization by Andy Lee Robinson.
That situation is changing. Scientists have long predicted that climate change would occur most rapidly in the Arctic, and that is exactly what’s happening. As warming temperatures cause snow and ice to melt, they expose darker land and water beneath them. Dark surfaces absorb heat from the sun, causing more melting, which exposes more land and water, leading to even more melting and creating a feedback loop.
The problem is exacerbated by black carbon (soot) emissions from cities and factories in mid-latitudes that get carried in the atmosphere northward to the Arctic. There they settle onto snow and ice, darken the surfaces, and cause more melting.
For more than 50 years now, the Arctic has been warming at twice the rate of the Earth as a whole. Sea ice is thinning and shrinking, the area and duration of snow cover are declining, and permafrost is thawing. Greenland alone loses more than 375 billion metric tons of ice annually. The volume of freshwater added to the Arctic Ocean in recent years is equivalent to the combined annual output of the Amazon and Ganges rivers.
Why should we care? Apart from the impact on Arctic ecosystems and human populations, climate change in the Arctic has wide-reaching effects. Since the early 1970s, the Arctic has been the dominant contributor to rising sea levels worldwide. The loss of sea ice—which floats on the surface of the ocean like ice cubes in a glass of water—has no effect on sea level. But the melting of land-based ice such as the Greenland Ice Sheet causes sea levels to rise. Greenland accounts for about 70% of the Arctic’s contribution to sea level rise and is expected to continue losing ice at a rapid rate. Coastal communities around the world will see increasing risks of flooding in the decades ahead, especially when higher sea levels are combined with storm surge.
Changes in the Arctic’s climate also affect ocean circulation—and may even affect weather in mid-latitudes. The connections between Arctic change and mid-latitude weather are complex and the subject of much debate among climate scientists. But there is some evidence that rapid warming in the Arctic may affect patterns in the jet stream, thereby affecting temperatures much farther south.
Arctic soils hold about half of the world’s soil carbon, and thawing permafrost could cause huge releases of methane—a potent greenhouse gas—in the decades ahead. If that happens, it will exacerbate climate change everywhere, not just in the Arctic.
What can we do?
It’s too late to stop climate change, but we can slow it down. Studies suggest that substantial reductions in global emissions of greenhouse gases, on the scale of those envisioned under the 2015 Paris Agreement, would reduce projected sea level rise by more than 40% by the end of this century. Governments, businesses, and individuals can make this vision a reality by taking aggressive steps to reduce emissions of heat-trapping greenhouse gases.
The Arctic Council—essentially a United Nations for the eight countries whose territories extend into the Arctic—coordinates scientific assessments and policy recommendations related to Arctic environmental change. ICF contributes to this effort through our support for the U.S. Global Change Research Program, which works closely with the Arctic Council’s Arctic Monitoring and Assessment Programme (AMAP). ICF staff played major roles in developing the Summary for Policymakers for AMAP’s 2017 Snow, Water, Ice, and Permafrost in the Arctic assessment, as well as a follow-on report in 2019 and a forthcoming assessment to be released in 2021.
No matter what we do, however, the Arctic’s environment will continue to change dramatically in the decades ahead. That means placing a priority on building the resilience of Arctic communities through infrastructure and other improvements, helping them prepare for and adapt to future conditions. Coastal communities around the world also need to assess their vulnerability to rising sea levels and develop plans to adapt over time. ICF works with local, regional, and national governments worldwide to assess climate change vulnerabilities, perform risk assessments, and develop adaptation strategies that reduce risk and build resilience.