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About 3 trillion tonnes of Antarctic ice has melted over the past 25 years

About 3 trillion tonnes of Antarctic ice has melted over the past 25 years
Science2 min read

  • An iceberg with 6000 sq km area broke off Antarctica on Wednesday.
  • The largest iceberg that broke off Antarctica, a few years ago, is nearing the end of its lifespan.
Antarctica is shedding ice at an alarming rate. Using the data recorded by satellites, researchers have noted that the continent was shedding about 200 billion tonnes of ice per year. That’s a threefold increase in the melting rates of Antarctic ice since 2012.

This is pushing up global sea levels by 0.6 mm every year. These new numbers were recently reported in a report published in Nature.

On Wednesday (June 13), a satellite that was above Antarctica observed one of the biggest icebergs ever recorded break away from the continent. The giant block of ice is estimated to be approximately 6,000 sq Km in area. That’s greater than Greater London and many other cities around the world.

In the past century many icebergs have broken off the Antarctic and according to recent reports, the largest iceberg one of these is nearing the end of its voyage. When the iceberg broke off in May 2000, it was recorded at a massive 296 km in length and 37 km in width. Over the past two decades, it fractured into smaller icebergs and most of them have melted away. As of 2018, just four remaining pieces can be tracked by satellites, which means they are smaller than 37 km in size.

Scientists who headed this research also say that the ice in Antarctica could be melting about five meters from its base every year. This is probably due to the fact that the environment is too warm for the Antarctic continent. It is about half a degree Celsius warmer than what the continent can withstand.

The melting process has accelerated

Scientists have been using satellites since the early 1990’s to monitor the ice sheet of Antarctica. This allows them to note the ice present at a particular time by measuring changes in the height of ice sheets and the speed at which it moves towards the sea. Some satellites can also weigh the ice sheets by sensing the change in the pull of gravity as they pass over the sheets.

Scientists usually divide Antarctica into three different regions - West Antarctica, East Antarctica and the Antarctic Peninsula.

According to the report in Nature (cited above), West Antarctica loses 159 billion tonnes of ice per year. This is a three-fold increase found over the past 25 years. And the Antarctic Peninsula’s losses have also risen from seven billion tonnes in 1992 to 33 billion tonnes in 2017.

East Antarctic is the only region where scientists have noticed some positive progress. According to the data, this region adds about 5 billion tonnes of ice over the year and is not subjected to the same speed of melting seen elsewhere. But this growth is not significant enough to counter the losses the continent encounters in the west and on the Peninsula.

In total, the white continent has cast off about 2.7 trillion tonnes of ice since 1992, which corresponds to an increase in global sea level by more than 7.5mm.

At the moment, scientists have projections of up to the year 2100 and have estimated that the sea-level will rise by 50-60cm, according to a report by the BBC.

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