[ad_1]
According to recent satellite photos, the Pine Island glacier in Antarctica has developed a 30-kilometer fault, indicating that it may soon lose another part of its volume. Geoscientist Stef Lhermitte, an assistant professor at the University of Delft in the Netherlands, tweeted on September 17 a contrasting gif with a flawless glacier, the same glacier showing a visible fault on October 1, indicating that the huge crack appeared in the last two weeks. of September.
It is normal for icebergs to break away from glaciers, but the Pine Island Glacier, one of the largest in West Antarctica, is beating icebergs at a particularly fast pace. About a year ago, he calved a huge iceberg of 103 km2; in 2015, a block of 225 km2 was detached and in 2013, an iceberg of 252 km2 was detached. Lhermitte estimates that the current break-up could result in an ice loss of approximately 115 square miles, which would be the sixth major calving event on the Pine Island Glacier since 2001. In these GIFs, you can see the following. evolution of the "fronts" of the glacier:
Scientists are also concerned about the way the ice on Pine Island Glacier is melting. While cracks generally form on the flanks of glaciers, new cracks have formed on Pine Island, more inland than before, suggesting that warmer ocean temperatures could weaken the base of the glacier.
The loss of Pine Island ice has serious consequences for sea level rise; Scientists estimate that if the entire glacier melts, it could raise sea level by 1.7 feet (about half a meter). This is unlikely to happen right away, but the models suggest that, if we do not reduce greenhouse gas emissions, ice loss from glaciers such as Pine Island could result in higher water levels. sea greater than one meter. There is evidence that the melting process is accelerating: the rate of ice melt has tripled (pdf) in the Western Antarctic region over the last 15 years and the total melting of glaciers in the region currently accounts for 5 to 10% of the sea level rise (paywall). . To understand how much ice is melting each year in West Antarctica, here is an evocative statistic from NASA:
The total amount of losses averaged 83 gigatons per year (91.5 billion US tons). In comparison, Mount. Everest weighs about 161 gigatons, which means that the Antarctic glaciers have lost a quantity of water equivalent to Mt. Everest every two years in the last 21 years.
According to Lhermitte, if this iceberg comes from Pine Island, the glacier will have dropped about 4 miles.
Source link
