Anderson, Robert, Natural History
For anyone not affected by the Indonesian tsunami, memory of the catastrophe has begun to fade. Nevertheless, a year later, it's worth remembering the tragedy and asking what's being done to save people from future killer waves. The tsunami of December 26, 2004-triggered by one of the largest earthquakes recorded since 1900-spread outward at nearly 500 miles per hour, leaving nearly 300,000 people dead across the Indian Ocean.
Space-borne cameras recorded the destruction in remarkable detail. Go to DigitalGlobe (www.digitalglobe. com/tsunami_gallery.html) for beforeand-after images of coastland that turned brown as the waters swept them clean of vegetation. Scroll down to the images of KaIutara, in Sri Lanka, where swirling floodwaters surged in violent retreat from the beaches. The Center for Remote Imaging, Sensing and Processing at the National University of Singapore has more satellite images (www.crisp. nus.edu.sg/tsunami/tsunami.html). Another site at NASA has Landsat 7 images of the hard-hit Sumatran coast, where monster waves plowed inland for a mile or more (www.nasa.gov/ vision/earth/lookingatearth/Landsat_ Tsunami.html). A variety of si tes inventoried at serc.carleton.edu/NAGTA/Vork shops/visualization/collections/tsunami_ other.html give a feel for how the waves propagated through the ocean. Click on "Tsunami Visualization Collection" in the box near the top for an array of animations that show how the catastrophe unfolded. For example, scroll down to "Tsunami Generation" near the bottom for a QuickTime video showing how slippage in the Earth's crust can lift huge volumes of water to form the destructive waves.
By chance, the Indonesian event was the first major tsunami detected from space as it took place. Unfortunately, it's not practical to rely on satellites to detect tsunamis, primarily because a huge orbiting fleet would be needed for appropriate coverage. …