By Andrea Thompson updated 12:20 p.m. MT, Tues., March. 25, 2008 A vast ice shelf hanging on by a thin strip looks to be the next chunk to break off from the Antarctic Peninsula, the latest sign of global warming’s impact on Earth's southernmost continent. Scientists are shocked by the rapid change of events. Glaciologist Ted Scambos of the University of Colorado was monitoring satellite images of the Wilkins Ice Shelf and spotted a huge iceberg measuring 25 miles by 1.5 miles that appeared to have broken away from the shelf.