Barrow, Alaska
Climate Change Daily Repost

Climate Change Goes Local – Day 3: Melting Permafrost

Barrow, Alaska

Barrow Alaska: A disappearing way of life

Travel north across Alaska and then keep traveling. After you pass into the Arctic circle and reach the continental edge, at the junction of the Chukchi and Beaufort seas, you will find America’s northernmost city — Utqiaġvik, formerly known as Barrow. The Iñupiat, an indigenous Inuit ethnic group, has occupied this land for over 1,500 years. But life in Barrow is rapidly changing.

The Arctic is warming faster than the rest of the planet, and this excess heat is literally melting a way-of-life into oblivion. Tundra lakes are disappearing, and melting permafrost dumps unwanted silt into the rivers, clogging them and choking ecosystems. Trees have spread into the tundra, and wildfires, unheard of in the past, spring up. The local dialect doesn’t even have a word for “forest fire.”

The tribes and local residents see these changes. In a Smithsonian article, Bob Reiss writes about Edward Itta, a local mayor, and Inupiat whaling captain. Itta says:

Barrow is ground zero for climate-change science. We worry that climate change is shrinking the sea ice and we don’t know how that will affect the animals that depend on it. At this time there is no effective plan if a catastrophe such as a ship collision or oil spill occurs. The Coast Guard hasn’t decided what its presence will be in the Arctic. Someone needs to monitor new traffic as the ice recedes and when tourist ships come through the Northwest Passage, which is already happening.

The whale is central to our culture.”… “The warmer ocean and currents will markedly shorten our spring whaling season. The impacts are around us already. We need more baseline science so we can measure these impacts over time.

Arctic Warming

Arctic warming is a vicious cycle. Heat melts the permafrost releasing carbon dioxide, which amplifies the warming and causes more permafrost to melt. This cycle is significant because it triggers two feedback processes that strengthen the rate of global warming. The first of these processes centers on carbon. The Arctic contains the largest carbon reservoir on the face of the earth, and that carbon is stored as organic matter, frozen into thick layers of Arctic permafrost. This permafrost is a ticking carbon bomb waiting to explode.

The earth’s atmosphere contains 850 gigatons of carbon. However, there are an additional 1,400 gigatons of carbon in the Arctic, waiting patiently for release from a frozen cage. Also stored in the Arctic are large reservoirs of methane. Methane is about 85 times more effective as a greenhouse gas than carbon dioxide (CO2).

Bacteria and methane hydrates

Rising temperatures affect these carbon stores in two ways. When the Arctic permafrost thaws, bacteria feast on organic matter in the soil. The byproduct of this bacterial party is CO2 and methane. These added greenhouse gases start a feedback loop that amplifies Arctic warming forcing local changes upon Barrow and the surrounding territories.

Arctic methane is also stored in clathrates (methane hydrates). When temperatures are low, and pressures are high, conditions are ripe for forming clathrates. During the formation process, large amounts of methane become trapped within water crystals, forming a substance similar to ice. The Arctic contains large deposits clathrates in shallow seas and permafrost.

Clathrates become unstable and release their methane if temperatures rise or confining pressures drop. If temperatures rise high enough in the Arctic, these clathrates will release their methane payload into the atmosphere, further exacerbating warming.

Sea ice versus open ocean

There is another feedback loop also at work heating the polar environment in a process called Arctic Amplification. This process involves a temperature feedback mechanism from solar radiation. As more ice melts due to hotter summers, less ice is left to start the winter freeze, and the winter ice cover is then thinner and weaker. Thus, when summer returns, it is easier than the year before for the sun to melt the thinner sea ice, meaning there is even less ice the next winter.

The Arctic summer sea ice extent has decreased by 40% over the past 40 years. Arctic Amplification is not a fantasy; it is already an active component in increasing the rate of climate change. The fabled Northwest Passage, which eluded explorers for hundreds of years, will become a reality by the mid 21st century, and the traditional lifestyles around Barrow, Alaska, will disappear.


When climate change goes local, it gets personal.


Sources:

Cohen, J., Pfeiffer, K. & Francis, J.A. Warm Arctic episodes linked with increased frequency of extreme winter weather in the United States.Nat Commun 9, 869 (2018) doi:10.1038/s41467–018–02992–9

Methane Hydrates and Contemporary Climate Change By Carolyn D. Ruppel (U.S. Geological Survey, Woods Hole, MA) © 2011 Nature Education Citation: Ruppel, C. D. (2011) Methane Hydrates and Contemporary Climate Change. Nature Education Knowledge 3(10):29

William House
William is an earth scientist and writer with an interest in providing the science "backstory" for breaking environmental, earth science, and climate change news.

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