Monday, April 3, 2017

Greenland Ice Past Tipping Point



Ice caps and glaciers along the coast of Greenland passed a tipping point in 1997, when a layer of snow that once absorbed summer meltwater became fully saturated. Since then, the coastal ice fields—separate from the main Greenland Ice Sheet—have been melting three times faster than they had been, according to a new study published Friday in the journal Nature Communications.
"The melting ice caps are an alarm signal for the ice sheet. It means long-term ice mass loss is inevitable. It will increase and accelerate if nothing changes," said lead author Brice Noël, a scientist at the  University of Utrecht Institute for Marine and Atmospheric Research. "It's very unlikely the ice caps will recover. It's a climate tipping point—the time at which a change or an effect cannot be stopped."
Climate scientists are wary of tipping points, when a series of small changes make a much larger change inevitable. The fear is a total meltdown of the Greenland Ice Sheet, which would raise global sea level by 24 feet, Noël said. Overall, the rate of ice sheet melting is accelerating, according to peer-reviewed studies cited in the most recent Arctic report from NOAA
 The melting of ice on Greenland is only part of what is happening all over the world, including the Antarctica.  But just considering the ice on Greenland with 24 feet of increase in the sea level, we're talking about serious flooding of every coast in the world, including Florida and Louisiana, and New York, Venice, large parts of Bangladesh, India, Thailand, and on and on.  But also where I live, Seattle.  Southcenter Mall will be under water.  Downtown Seattle is built on a bluff, but when the Puget Sound rises 20 or more feet, the bluffs are coming down.  And this will happen in the lifetime of my children and grandchildren.

There isn't any way that anyone could possibly understate the urgency for solving climate change.