'We have passed the tipping point' Massive Antarctic Glacier Uncontrollably Retreating

There goes the neighborhood!
(less than 50%)

Massive Antarctic Glacier Uncontrollably Retreating, Study Suggests
Pine Island Glacier accounts for about 20 percent of the total ice flow on the West Antarctic Ice Sheet — an amalgam of glaciers that covers roughly 800,000 square miles (2 million square kilometers) and makes up about 10 percent of the total ice on Antarctica. Many researchers think that, given the size of Pine Island Glacier, 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 (3 and 5 meters).

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.

'We have passed the tipping point'
[link to news.yahoo.com]