Associated Press: The huge West Antarctic ice sheet is starting a glacially slow collapse in an unstoppable way, two new studies show. Alarmed scientists say that means even more sea level rise than they figured. The worrisome outcomes won't be seen soon. Scientists are talking hundreds of years, but over that time the melt that has started could eventually add 4 to 12 feet to current sea levels. A NASA study looking at 40 years of ground, airplane and satellite data of what researchers call "the weak underbelly...