Two years ago, a NASA satellite observed a large crack cutting through the Pine Island Glacier in Antarctica – here you can see some amazing images of the development of the fissure. Just a couple months ago, the crack expanded enough to completely sever a massive iceberg from the glacier. This alone will not increase sea levels, however scientists are concerned that warm water below the iceberg may be cutting away at the ice and melting it more quickly than expected.
Now, as reported in Science, the first hard data has been reported showing this surprisingly quick melting rate below the Pine Island Glacier. A group of researchers, headed by Dr. Tim Stanton at the Naval Postgraduate School, spent the past several years preparing gear and equipment for a trek to the Antarctic to measure the melting rate on the bottom surface of the glacier. To their surprise, they found that fast flowing river channels below the glacier were melting the ice at a rate of 2 inches per day, unchanged over the course of 35 days of measurement. If this rate were continue over the course of year (which is unlikely), it would amount to 50-80 feet of melted ice for a single channel (usually about 2000 feet wide). This surprising result provides evidence for another important source of glacier melting that will now be included when projecting future sea level rises.