I watched this NOVA presentation over the holidays, and while you might think that nothing could move as slow as a glacier, they are unfortunately not shifting all that slowly. The scientists on the program were able to measure movement that, while imperceptible to the naked eye, equaled about 130 feet per day. That is amazing. And alarming.
Researchers at the American Geophysical Union annual meeting in San Francisco reported last month that rising sea levels over the next century may be much greater than even they had anticipated:
The vast Greenland ice sheet is melting at an increasingly rapid rate—much faster than most conservative estimates made by, among other authorities, the UN’s own Intergovernmental Panel on Climate Change (IPCC). In the last decade, scientific technologies have made fast advances toward more confident and precise measurements of the complex changes in the Greenland ice sheet.
Previous estimates by the IPCC were kept low because there was so much uncertainty in the measurements. Many suspected it was melting faster, but at best could only support such claims anecdotally. This scientific uncertainty has been cast erroneously by some as evidence that the risk of glacial melting was being exaggerated. It was always a distinct possibility that the ice sheets were melting more rapidly.
I hope to entice some of our own UGA/Franklin scientists and geologists into this discussion on the blog this year. Stay tuned.