by Robert Wilkinson
Studies now indicate “The glacier that contributes more to sea level rise than any other glacier on Antarctica has hit a tipping point of uncontrollable retreat, and could largely collapse within the span of decades...” This is extremely not good for our children and grandchildren.
The study findings were originally published earlier this month in the journal Nature Climate Change. This story comes from NBC news, in a story by Laura Poppick titled Massive Antarctic glacier uncontrollably retreating, study suggests. In it we read that Pine Island Glacier makes up 10% of the total ice on that continent, and that “its demise could have a domino effect on surrounding glaciers and ultimately – over the course of many years – lead to the collapse of the entire ice sheet, which would raise average global sea level by between 10 and 16 feet.”
Wow. Given that over 80% of the world’s population live near water, this will be a global catastrophe for billions of people dislocated from the coasts and riverfronts. And of course, this study has nothing to do with the fact that Greenland is also melting more quickly than in the past, and will also contribute to the global rise in water levels in coming decades. From the story:
The glacier is not only massive, but also one of the least stable of the West Antarctic Ice Sheet ice flows. In the past 40 years, its melting rate has accelerated due to relatively warm ocean currents that have seeped underneath its base and lubricated its flow seaward. As it slips into the ocean, the glacier's ice shelf — the part that floats on water and extends beyond the glacier's base — disintegrates through a natural process called calving, exposing yet more of the glacier to warm waters. Last year, an iceberg larger than the city of Chicago broke off into the surrounding Amundsen Sea.
... Researchers based at the French National Center for Scientific Research in Grenoble have now developed state-of-the-art models that, while still limited, provide the best estimates yet of the future behavior of Pine Island Glacier, they say. The team has found that the glacier's grounding line — the point where glacier and its ice shelf meet — is about to retreat over an oceanic trench that would increase the amount of water that seeps underneath and melts the glacier. Their models suggest that this would cause the glacier to uncontrollably retreat about 25 miles (40 kilometers) over the next several decades, potentially raising global sea levels....
Retreat may slow once the glacier passes the trench, the researchers report, but it will not likely regain stability or enter a positive-growth phase.
And yes, we’re told that predictions of future behavior of ice sheets always have some margin of error due to assumptions, and we also find that various La Nina phenomena have a very big impact on the rate and location of where the melting is occurring. By all means, go to the original article, since it has several internal links to stories related to the science of what’s published here.
This is another example of what I gave you in How to Anticipate the Future. The fact that Antarctic ice melt has definitely accelerated and in all likelihood will not be reversed clearly shows us that we’ve left the era of “survival of the fittest” and entered the next phase of human evolution which offers “survival of those who learn to think in the future.”
Flexibility is a virtue in an Age in Transition.