Seals from Space Sea creatures are our next army of environmental-data collectors

Meet the newest ocean sensors: elephant seals. These zigzags represent the migration patterns of 11 females between Baja California and the Gulf of Alaska. iPod-size satellite tags glued to their heads recorded the depth, temperature and salinity of the water they swam through and then relayed the data to researchers. The Tagging of Pacific Pelagics initiative, a program of the Census of Marine Life, plans to outfit 23 marine species, including bluefin tuna and white sharks, with 6,000 tags by 2010. One surprising finding so far: A weird warming of California coastal waters in 2005 forced tagged sea lions to venture offshore up to 300 miles in search of food.

Arctic MeltdownRipples mark a dramatic 3-D view of a shrinking glacier

The frozen lobe of the behemoth Malaspina glacier wrinkles as the faster-moving valley glaciers behind it push it toward the Gulf of Alaska. To create this accurate 3-D view, NASA scientists draped a satellite image over detailed topographical data acquired during a flyover of the space shuttle Endeavour in 2000. The project was the first to map the elevation of ice masses in high resolution around the world, providing scientists with baseline measurements with which to gauge future changes.

The shallow end of this Rhode Islandâ€size glacier is melting swiftly. Glaciologists have determined that areas of the glacial lobe were 98 feet lower in 2004 than they were in 2000. That's double the rate of pre-1999 thinning.