PRI: As climate negotiators slog through the latest UN summit in South Africa with no breakthrough on greenhouse gas limits in sight, the science of climate changeespecially melting iceis racing ahead of the world's response to the problem. The day after this year's UN climate summit ends this Friday, a research team is scheduled to fly into a remote corner of Antarctica for a visit to the Pine Island Glacier. It's the biggest ice shelf in western Antarctica. And it's movingfast. "This is the fastest...