While Foreign Ministers met together in the Arctic Council Ministerial meeting last month, a growing concern about Antarctica climatic threshold raised on the other side of the planet.
Why is Antarctica critical?
The Antarctic has long-time been known as Earth’s largest glacier, which is equivalent to 57.9 meters of global mean sea level (GMSL). For instance, Thwaites Glacier in West Antarctica has an open terminal in the Amundsen Sea. Its main trunk is about 120km wide, widening upstream into the heart of the West Antarctic Ice Sheet. Currently, the terminus is under the seawater too shallow, about 600 meters deep, that causes cliff faces to become unstable. The thawing process continues into deeper bedrock and thicker ice, with strained variability rates exceeding thresholds for brittle failure. As a result, Antarctic glaciers are incredibly vulnerable (can be thinner and broken up) when shelves are abraded from contact with warm sub-surface waters.
According to the latest research, the desolate Antarctic will undoubtedly be the place with the most significant influence on the future habitat of humankind.
Future Scenarios from Antarctica
According to scientists1, the Antarctic ice sheet could reach a critical threshold value ice loss continues to be extensive. It is severe because ice shelves are extremely vulnerable to oceanic melts from below and above warming to surface warming. As Antarctic ice shelves (AIS) break up, ice cliffs may not stand on their position because of their susceptible ability to dynamic instabilities that cause the rapid retreat, resulting from parts of AIS below sea level. Meltwater and rain may deepen crevasses which in turn then cause flexural pressures, leading to hydro-fracturing and ultimately ice-shelf collapse. Furthermore, due to the strong dependency of crack growth with melting and/or fractured surfaces, a previously unseen ice failure probably has already occurred in the Antarctic glaciers.
Therefore, if we apply current climate policies (allowing 3 degrees Celsius of warming), the pace of Antarctic ice loss may constitute about 0.5 centimeters GMSL rise per year by 2100, the sea level rise could be accelerated dramatically, and by 2300, sea level could rise ten times more than estimated if climate policies do not meet the Paris Agreement goals. There are many reasons for the increase in sea level, but another study2 led by Robel, A., Seroussi, H., and Roe, H. G. finds that the collapse of the Antarctic ice sheet is the worst case for the future projections in the rise of sea levels. It has the capability to lift sea levels by 200ft (60m).
What can we do to reduce the magnitude of sea-level rise?
According to the Paris Agreement of 2016, most countries will need to keep global warming limited to under 1.5 degrees or 2 degrees Celsius of rising temperatures. Decarbonization strategies and clean energy policies will be the main focuses in replacing the post-industrial era’s technology. So far, they target to reduce 50% to 60% of emissions; however, current policies globally would result in just a 1% emissions reduction by 2030. If we do not want the collapse to happen early, the reduction should be carried out as quickly as possible.
As countries prepare to increase their Paris Agreement pledges in the run-up to a United Nations Framework Convention on Climate Change in November—COP26 in Glasgow, we should remember that every fraction of a degree matters. Applying policies allowing global warming to exceed 2 degrees is not a realistic choice for coastal communities or the global economy because coastlines at that time are under many feet of water, causing devastating economic impacts. Furthermore, new policies must take all reasonable precautions against irreversible impacts on Antarctica’s ice and the world.
While physical instabilities in the Antarctic glaciers can result in a rapid acceleration in sea level rise, its magnitude can be drastically decreased by global emitters meeting the Paris Agreement goals.