One year, 900 locations, thousands of coral reefs. That's the tally
of NASA's Landsat 7 satellite as it continues to deliver cutting edge
images and information about the Earth. Data being presented this week
at an international conference in Indonesia is the first assessment of
the physical condition of major reefs from the the new Landsat 7
collection of images. More than 5000 coral reef scenes have been amassed
in the first year of Landsat 7's operation. In that collection, many
reefs have been seen more than once, offering scientists an opportunity
to study seasonal variations as well as other changes in the reefs
caused by hurricanes and climate change.
This image shows coral communities in the Florida Keys.
Coral is the ocean's architectural memorial to the lives of deceased
coelenterates. The word "coelenterate" refers to the central body cavity
found in the creatures. Located in tropical latitudes, the hard
structures we know as coral are really the incremental build-ups of
calcium carbonate deposited from the skeletal remains of these tiny
In many parts of the world coral is threatened from a variety of
causes, some natural, some caused by people. By developing a global,
searchable database of coral reefs based on state-of-the-art satellite
data, researchers could have a powerful new tool for studying this vital
and elegant part of the Earth's biosphere. This will help them not only
develop better strategies for conservation, but help them refine methods
for understanding what processes drive change in the world's oceans.