What’s Going On Here?
The Greenland Ice Sheet (GrIS) is melting at such a high rate that even if global heating were to stop today, the ice would continue to disappear.
What Does This Mean?
According to a new study conducted by scientists at Ohio State University, the world’s second largest ice sheet has reached a tipping point, whereby annual snowfall is no longer able to replenish the melting of surface ice.
Researchers analysed 40 years of monthly satellite data from more than 200 glaciers flowing into Greenland’s oceans. They found that since 2000, whereas the amount of ice lost has increased due to global heating, annual snowfall rates have remained fairly constant and thus the ice sheet has lost ice at a faster rate than it is being replaced.
Scientists now believe that the ice loss so profound it has activated an irreversible feedback loop, whereby even if humans were able to somehow stop climate change in its tracks, the ice sheet would continue to shrink for some time.
Why Should We Care?
Sea level rise is a well-known consequence of human-induced climate change, both from the melting of glacial ice and the thermal expansion of seawater. The melting of glaciers in Greenland is a global problem, with ice that melts or breaks off from Greenland’s ice sheets entering the Atlantic Ocean and eventually all of the world’s oceans. Since 2000, this melting has caused around 1 millimetre of global sea level rise per year. If the entire ice sheet were to melt it is estimated that this would cause in excess of seven metres of global sea level rise, which would flood some of the world’s megacities, such as the capital cities Dhaka and Jakarta.
This is a hugely costly consequence of climate change. Global sea level rise of just 1 metre would require more than $70 billion of annual spending on sea walls and other flood defence infrastructure.
Yet whilst this is a global issue, the severity of the impacts of sea level rise are disproportionately distributed amongst island nations and developing countries with high population density, in particular Asia and the Pacific region, where around 59% of the global population live.
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