changing world. >> you are at the mercy of the elements. >> this is the story of what it takes to survive on the edge of the world. it's the start of another all too brief summer. patagonia's 600 glaciers are rapidly melting. fresh water cascades off the mountains. as it pours into the fjords, it mixes with saltwater, stirring up the water columns and drawing up nutrients from the depths, feeding more and more plankton, which in turn supports an entire