In 2014 studies showed that the West Antarctic Ice Sheet was being destablized by warm ocean currents coming up under the tidewater glaciers. The warm water was melting the base of the glacier, and causing the grounding line to retreat inwards towards the center of the ice sheet. However, because the submarine topography below the glaciers tilts downwards toward the center of the ice sheet, this creates an instability that will lead to the total collapse of the ice sheet, and a sea level rise of about 3 m (ca. 10 feet).
Now a new study shows that at least part of the much larger East Antarctic Ice Sheet is being destabilized in the exact same way. The drainage basin of the Totten Glacier in East Antarctic is beginning to be affected by warm ocean currents melting the tidewater portion of the glacier, resulting in a thinning glacier, faster glacier flow, and an increase in the rate at which ice is being dumped into the sea. These processes will eventually cause sea level to rise by another ca. 3 m.
Combine the water from these two Ice Sheets with water from the melting of the Greenland Ice Sheet, and the earth is now on track for 8-10 m (25-30 feet) of sea level rise.
The projected loss of glacier ice from Greenland and Antarctica and the concomitant sea level rise of 8-10 m (25-30 feet) will take hundreds of years to complete. However, it is disquieting that the assurances given just a couple of years ago that the Antarctic sheet was stable and secure are now shown to be completely wrong, and the cumulative potential for sea level rise from melting parts of the Greenland Ice Sheet, West Antarctic Ice Sheet, and East Antarctic Ice is becoming distressingly large.
Now that we know we are on track for up to 10 m (30 feet) of sea level rise in a few hundred years, the possibility that we may see 1-3 m (3-9 feet) of sea level rise by the end of this century becomes quite a bit more likely.
Is it too early to apply for the gondola concession in New York City?
No comments:
Post a Comment