Last week marked Arctic Matters Day hosted by the National Academy of Sciences. The free, public program highlighted results from research into the environmental changes happening in the remote region and how those changes will ultimately affect us all.
Last month, at a meeting of over 20,000 scientists from the American Geophysical Union, the National Oceanic and Atmospheric Administration (NOAA) issued an Arctic report card for 2015. Its marks were not good. The maximum extent of arctic sea ice occurred two weeks earlier than in previous years and was the lowest on record. The sea ice that is present also turns out to be younger and thinner, with twice as much “first year” ice than was observed thirty years ago. The report further notes the profound effects of this waning sea ice on the local habitat, including fish, walruses, and average sea temperatures.
NASA has released a video showing the difference between the current ice cover and the extent of the ice in years past. The largest difference is just north of Japan where the ice falls roughly 350 miles short of its past extent.
Due to the clear link to their diminishing habitat, polar bears have become the poster children for the direct impact of this lost Arctic sea ice. But how does this missing ice affect the rest of us? How are our futures connected to the future of the polar bear?
Here are six ways the impact of melting Arctic sea ice is already being felt in the Arctic and beyond.
1.) Travel in the Arctic is getting riskier.
Temperatures in the Arctic are warming twice as fast as global averages, and native Arctic communities are clearly experiencing the most immediate impact from the loss of ice. Many hunters in the region that rely on snow mobiles for transport across the ice cite increasingly unpredictable weather patterns and unexpectedly thin ice as new dangers in traditional hunting schedules.
2.) The politics of the Arctic are changing.
At the same time, as Arctic sea ice melts, more and more of the Arctic becomes passable to ships. Already the potential of these new passages are being explored for mining for rare minerals used in electronics, as well as for oil drilling and tourism. These ventures lead to the possibility of destructive spills and further habitat disruption, but they also add greater political influence to the voices of the indigenous Arctic people.
3.) Melting Arctic Sea ice affects global weather patterns.
As we know from hurricanes, the weather we experience is directly influenced by the temperature and direction of ocean currents. The melting of Arctic sea ice can have a dramatic effect on the flow of ocean water, through a change to the overall global temperature gradient and through a decrease in ocean salinity thanks to the large influx of fresh water, both of which can influence the strength and frequency of storms. Sea ice further regulates how much moisture is transferred from the ocean to the atmosphere, another direct link to weather patterns.
The jet stream, an air current that forms when cold air from the Arctic meets warmer air from the tropics, has a dramatic influence on the weather experienced in the Northern hemisphere. Since temperatures are rising faster in the Arctic than they are globally, this lowered temperature gradient makes the jet stream less intense and thus could lead to longer periods of drought and intense heat as well as cold snaps like the so-called Polar Vortex of previous winters.
4.) Arctic ice melt results in rising sea levels.
The influx of large amounts of fresh water that results from Arctic ice melt has to go somewhere, and it often results in rising coast lines. A few extra inches of sea shore may not seem like much, but every little bit counts, especially during intense storms like Hurricane Sandy, which led to flooding along the New Jersey coastline.
5.) A lack of Arctic sea ice impacts global temperatures.
10% of the world’s fish supply and nearly half of the U.S. fish supply comes from Arctic and subarctic waters.
The sea ice helps keep global temperatures low by reflecting sunlight. Similar to how wearing a white shirt on a hot day will keep you cooler because it reflects more of the sun’s rays than a darker color will, the white ice is better at reflecting sunlight than the darker ocean below it. Warming effects (like the melting of sea ice) that in turn lead to even more warming effects (like less reflected sunlight) are known as positive feedback loops.
6.) Arctic sea ice impacts a huge global food source: fish.
Without as much ice present, the Arctic Ocean can absorb more of the carbon dioxide in the air which seems like—finally—a bonus for global warming. However, the increased carbon dioxide in the ocean waters has adverse effects for many species of algae and plankton, which are the base of the Arctic food chain. Further, 10% of the world’s fish supply and nearly half of the U.S. fish supply comes from Arctic and subarctic waters.
Until next time, this is Sabrina Stierwalt with Everyday Einstein’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Everyday Einstein on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at everydayeinstein@quickanddirtytips.com.
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