“For the trouble at that time will be far more terrible than any there has ever been, from the beginning of the world to this very day. Nor will there ever be anything like it again.” Matthew 24:21
Antarctica's massive ice shelves are shrinking because they are being eaten away from below by warm water, a new study finds.
That suggests that future sea levels could rise faster than many scientists have been predicting.
The western chunk of Antarctica is losing 23 feet of its floating ice sheet each year.
Until now, scientists weren't exactly sure how it was happening and whether or how man-made global warming might be a factor.
The answer, according to a study published in the journal Nature, is that climate change plays an indirect role - but one that has larger repercussions than if Antarctic ice were merely melting from warmer air.
Hamish Pritchard, a glaciologist at the British Antarctic Survey, said research using an ice-gazing NASA satellite showed that warmer air alone couldn't explain what was happening to Antarctica. A more detailed examination found a chain of events that explained the shrinking ice shelves. Twenty ice shelves showed signs that they were melting from warm water below. Changes in wind currents pushed that relatively warmer water closer to and beneath the floating ice shelves.
The wind change is likely caused by a combination of factors, including natural weather variation, the ozone hole and man-made greenhouse gases.
This map shows Antarctica's ice shelves on the continent's western coast thinning, with the red portion indicating ice thicker than 550 meters, while blue is thinner than 200 meters.
Cause for concern: Scientist Hamish Pritchard claims that the melting and thinning of floating ice shelves could eventually trigger a rise in sea level.
Pritchard said that as the floating ice shelves melt and thin, it triggers snow and ice on land glaciers to slide down to the floating shelves and eventually into the sea, causing sea level rise. Thicker floating ice shelves usually keep much of the land snow and ice from shedding to the sea, but that's not happening now. That whole process causes larger and faster sea level rise than simply warmer air melting snow on land-locked glaciers.
The study concludes that the ice sheets are highly sensitive to relatively subtle changes in climate through the effects of the wind and what's happening in Antarctica may have already triggered a period of unstable glacier retreat.
If the entire Western Antarctic Ice Sheet were to melt - something that would take many decades if not centuries - scientists have estimated it would lift global sea levels by about 16 feet.
Andrew Cuomo said “I believe global warming and climate change are real threats to our planet.”
Yes, global warming is surely a threat of humanity but we just only feel warm.L
Source: Associated Press
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