Greenland's ice sheets melt beyond tipping point.

By Asher Rolls

31st August, 2020

Recent studies show that Greenland’s ice is melting faster than expected

(Source: bbc.com)

A recent study published by the journal Nature Communications Earth and Environment suggests that Greenland's ice sheet has molten beyond the point of return, hence contributing to an inevitable rise in ocean levels. According to the study, the accelerated rates of losing mass is the largest single contributor to rising sea levels. Greenland alone contributes 280 billion metric tons of melting ice into the ocean each year. What this means is that the snowfall that replenishes the ice sheet each year cannot keep up in pace with the amount of ice that is flowing into the ocean, from the glaciers. Scientists went through satellite data spanning 40 years of over 200 glaciers around Greenland. The analysts found that, all through the 1980s and 90s, the snow picked up through aggregation and ice dissolved or calved from ice sheets were for the most part in balance, keeping the ice sheet intact. Through those decades, the analysts found, the ice sheets, by and large, lost approximately 450 gigatonnes of ice each year from flowing outlet ice sheets, which was compensated by snowfall, they said. And this pattern was relatively steady until a massive increase in ice discharge to the ocean during a short period. By the 2000s the glaciers were losing around 500 gigatonnes of ice, but at the same time, the rate of snowfall remained the same. Through the previous decade, the rate of ice loss from ice sheets has remained around the same, which essentially means that the ice sheet has been losing ice more quickly than it's being replenished. And it is due to this very reason scientists say that even if global warming were to stop today, the ice sheet would continue to melt. Even in such a scenario, the ice sheet would only be able to gain mass once in every 100 years. Additionally, warm water seawater dissolves glacier ice, making it harder for the ice sheets to develop back to their previous positions. "Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss, even if the climate was to stay the same or even get a little colder, the ice sheet would still be losing mass," said Ian Howat, a professor of earth sciences and distinguished university scholar at Ohio State.

Sources: Axios, Nature.com

Edited by Hrishit Roy