Trillion Ton Iceberg Melts: Impacts Unpredictable

The journey of the giant iceberg that started four and a half years ago after splitting from Antartica has come to an end, but its impacts can be everlasting and the scientific community is yet to determine whether the impacts will be good or bad.

The iceberg split from the planet’s south pole region in July 2017 and was, during its lifetime, the biggest iceberg in the planet. With an area of 2,300 square miles (6,000 square kilometres), were it a city, it would be the seventh largest in the world or just about the size of Moscow.

A-68, as it was called, broke off the Larsen C ice shelf in Antartica and started drifting North to the Southeast of Argentina.

For the first two years, the mass remained largely the same size, but when it began to enter the warmer waters of the Scotia Sea, the melting rate increased substantially eventually shedding 1 trillion tonnes (900 million metric tonnes) of fresh water into the sea.

There were initial concerns that the iceberg was on a collision course with South Georgia Island, a British overseas territory with an area of just 1,450 square miles (3,500 square kilometres). There were fears that this might have cataclysmic consequences on the island’s wildlife, namely its population of penguins and seals. However, the iceberg melted enough to avoid impact and eventually disintegrated completely.

The evaporation of the iceberg has meant that the equivalent of 61 million Olympic-sized swimming pools (or 20 Lochs Ness) of fresh water has entered the ecosystem; the consequences are yet undetermined.

Icebergs hold water trapped in frozen state and, with it, other nutrients and substances. The release of cold meltwater will certainly have an immediate impact on the surrounding ecosystem that could be felt for generations to come. But the release of old water and old air could also have very unpredictable future consequences, the exact nature of which is still not known.

Climate change and global warming are causing glaciers and ice sheets to melt which, in turn, is causing sea levels to rise. In 2019, the Intergovernmental Panel on Climate Change (IPCC) released a special report on the on the state of oceans and cryosphere.

As reported in The water Diplomat, the Panel's report highlights the urgency of prioritising ambitious and coordinated action to cope with rapid, unprecedented and long-lasting changes in the frozen components of the earth caused by climate change. The report addresses water in its “cold” status: snow, glaciers, ice sheets, icebergs and sea ice, ice on lakes and rivers in addition to permafrost and seasonally frozen ground as well as ocean “health”.

The cryosphere represents about 70% of all fresh water on Earth, where the oceans represent 96.5% of all water everywhere. Put differently, the cryosphere and ocean represent, in turn, the majority of all potable water and all water on Earth.