By Siona Ahuja ’24
Staff Writer
Recent studies have confirmed that the Antarctic ice shelf is melting at irreversible rates. Industrial emissions from thousands of miles away have caused the depths of the Antarctic Weddell Sea to heat up five times faster than the rest of the ocean.
Warming trends in Antarctica have been mixed, with western parts of the continent steadily warming while the eastern region has remained relatively unscathed. Unlike the Arctic, which is known for having heated up exponentially within the past few decades, Antarctica’s behavior has proven to be more difficult to map out. Natural fluctuations of warm and cool ocean currents (which cause the El Nino and La Nina currents) over a long period have pushed warm winds over to the South Pole. This natural phenomenon is not the only driving force behind the Antarctic’s heating, as indiscriminate burning of fossil fuels has also been a significant factor in melting ice shelves.
Oceans consume more than 90 percent of excess heat generated by greenhouse gas emissions. These oceans also absorb large amounts of atmospheric shock. As a result, southern oceans have absorbed over half the heat generated from 2005 through 2017.
The mixing of warm southern oceanic currents, especially those enveloping Antarctica, means that deeper waters are heating faster than surface waters. The melting of Antarctic land ice into the sea also causes the ocean’s topmost layer to remain considerably cooler. This will eventually lead to what scientists at NASA’s Goddard Institute for Space Studies call a “heat flux,” where increased warming rates would cause the accelerated melting of ice shelves and a greater rise in sea levels, causing unmitigated disasters.
Climate scientists remain skeptical about the world’s ability to stop or decelerate the warming of the continent. The world’s second-largest emitter of greenhouse gases, the United States, formally exited from the Paris Climate Agreement on Nov. 4, 2020. Even if other countries fulfill the targets they set in this treaty, Antarctica’s fate remains sealed. Researchers believe that it will be difficult to counteract these changes if temperatures rise 2 C above pre-industrial levels.
Dr. Richard Jones and Dr. Ross Whitmore of the Monash University School of Earth, Atmosphere and Environment, are lead authors of the Oct. 21 study. They state that the study implies ice loss unfolding in Antarctica is “likely to continue unabated for a long time — even if climate change is brought under control.”
This change holds significant implications for the icy continent. The native animal population is decreasing. While some species are adapting to the heat, other populations are declining. Krill, small shrimp-like crustaceans crucial to Antarctica’s ecosystem, have also declined around 80 percent since the 1970s because of excessive commercial fishing, depleting ice and the recovery of whales.
Warming has also caused new kinds of algae to bloom, shading swathes of snow tints of green, red and pink. This alga is so vivid that it can be seen from space. Moreover, ocean warming exacerbates the thawing of sea ice. Darker sea ice has lower surface reflectivity. This causes more solar radiation absorption, furthering melt and creating a “feedback loop.” Land in Antarctica is also growing greener. Rising temperatures have led to the growth of plants, mosses and lichens, which might pave the way for a whole new ecosystem.
Expansion of the oceans gives way to numerous coastal disasters like floods and ice melting, which can endanger 40 percent of the world’s population that lives on coastlines. Scientists are certain this phenomenon will affect people living inland as well.
Antarctica is facing the consequences of human activity despite being secluded thousands of miles away from civilization. Just as the whole Earth has impacted Antarctica, the changes it sustains are felt globally. Researchers hope their findings ignite conversations and policy changes that can prevent any future major disasters.
