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2019-08-10


Sea Ice Melt in the Arctic
 
A
The thought of global warming often conjures images of long summers and dried-up agricultural fields. But few realise that the major impacts of this recent trend are most apparent, and most threatening, in the earth’s northernmost region. Arctic sea ice loss has increased exponentially in recent decades, posing a number of formidable environmental and security challenges. And because polar regions heat up faster, they are the most accurate indicators of what’s in store for global climate change.
 
B
According to the latest research, the Arctic ocean is losing about 78,000 square kilometers of ice annually, with the sea ice having dropped to its lowest recorded levels in 2012. The research reveals that the Arctic sea ice loss began in the mid-20th century, although NASA didn’t begin collecting satellite records of it until the 1970s. Computer models based on the collected data suggest that it is declining at a rate of up to 2 inches per day, or half a million square kilometers per decade. As a result, the Arctic sea ice is now half of what is was in the 1950s, and 40 percent of what it was in the 1980s. If this trend continues, the Arctic will have ice-free summers within the next few decades. 
 
C
There are many consequences of Arctic sea ice deterioration. First of all, less ice invariably means higher water temperatures. This is because ice reflects the sunlight that water otherwise absorbs. Increased water temperatures have an obvious impact on sea life and surrounding wildlife, but they also directly affect global weather patterns, wind flows, and the position of jet streams. Polar jet streams are narrow, fast-flowing rivers of wind high in the Earth’s atmosphere that push around cold and warm air masses and can determine weather. For example, increases in high-atmosphere air currents result in more summer rain in certain parts of the world, including Britain and northwestern Europe.
 
D
A significant side effect of the higher temperatures is Arctic glacial melt due to the warmer water flowing beneath the glaciers. Glacial melt creates immediate rises in sea levels and feeds into the negative cycle of further destroying sea ice. This has been observed not only in the Arctic but also on the opposite pole. Research at Pine Island Glacier, a 35-mile long ice tongue in the Antarctic, has proven that water temperature increases below glaciers are the biggest source of uncertainty in sea level predictions. If the Pine Island Glacier continues to recede at its current rate, a complete breakdown of the ice shelf is possible, which would release tons of water into the Amundsen Sea and raise global sea levels by around three to four feet.
 
E
The melting sea ice also contributes to greenhouse gases. There are massive stores of methane trapped in the permafrost and seabed in the Arctic. As the ice melts and the permafrost disappears, the methane is released into the atmosphere. While carbon dioxide is the gas we most commonly associate with global warming, methane also plays an important role. Emitted by agricultural activities, landfills, and the burning of coal and natural gas, methane is the second most damaging greenhouse gas. It is 60 percent more effective at trapping heat than carbon dioxide, and has much more complex interactions with other chemicals, such as aerosol that compound its negative atmospheric impacts.
 
F
Perhaps less discussed, however, are the economic and security implications. Governments of countries that border the Arctic region have been focusing more of their attention on the sea ice loss, and for good reason. As the Arctic sea ice melts, transportation through the region by water becomes easier. That may seem like a benefit, but it’s actually a source of concern. Easier transit means protecting one’s sea borders becomes more difficult, and more costly. Imagine how much money it will cost Canada to monitor its territory in the most northern areas, which are largely uninhabitable. But without the protection, it leaves the country vulnerable to illegal migration at best, and attacks at worst.
 
G
Then there’s the matter of trade, and what a more open Arctic sea means for the global economy. Already shipping and transit through the Bering Strait have increased by 118 percent since 2008. One million tons of cargo was shipped through the region in 2012 alone. This means that countries that have territorial rights to the Arctic region stand to gain economically through taxation of passing vessels, and through increased trade to their regions. For that reason, the five countries surrounding the Arctic—the United States, the Russian Federation, Canada, Norway, and Denmark—have stepped up to defend their portion of the pie.
 
H
More motivating for these countries, though, are the rich natural resources buried under the Arctic sea floor, such as crude oil, natural gas, and other minerals. The region is thought to hold approximately 12 percent of the world’s undiscovered oil reserves and 30 percent of its undiscovered natural gas and natural gas liquids. Given the state of depletion of many of these natural resources, and thus their high economic value, it’s no wonder that everyone’s in a race to claim the melting Arctic.