Satellites can spot tsunamis
Satellites can spot the leading edge of a tsunami, U.S. government
researchers said on Wednesday in a study that might lead to better ways
of detecting the giant waves and get people out of their way.
They went back and looked at satellite images in the Indian Ocean as
the December 2004 tsunami raced across to destroy coastlines in
Thailand, Sri Lanka and elsewhere. They found clear patterns in the
water.
"We've found that roughness of the surface water provides a good
measure of the true strength of the tsunami along its entire leading
edge," Oleg Godin of the National Oceanic and Atmospheric Administration
in Boulder, Colorado, said in a statement.
"This is the first time that we can see tsunami propagation in this
way across the open ocean."
A giant earthquake in Indonesia triggered the 2004 tsunami, which
killed more than 228,000 people.
Governments have since rushed to complete an early warning system of
mid-ocean buoys that would detect such waves as they pass by. But such a
system is imperfect and might miss areas, especially as the buoys cannot
be placed everywhere.
Tsunamis can only usually be seen when they enter shallow water. In
the depths of an ocean, the water they displace barely shows although
this tiny movement can also be detected by satellites. Reuters
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