Digital maps provide details of Hawai'i's ocean bottom
By Jan TenBruggencate
Advertiser Science Writer
A new series of digital maps details the shallow ocean floor off the main Hawaiian Islands.
You can order a CD-ROM of the Hawai'i maps online.
The maps were made using hyperspectral imaging, which employs specialized cameras to look through the water and identify what's on the bottom. They are available at the Benthic Habitats of the Main Hawaiian Islands Web site, biogeo.nos.noaa.gov/products/hawaii_cd/startup.htm.
Maps available on CD-ROM
The technology, employed from aircraft that fly over the coastline, can distinguish between 27 different ocean bottoms. For example, it can tell the difference between sandy and weedy areas, corals and lava rock, and mud and mixed bottoms.
An example: The map for the Mokule'ia area of O'ahu shows that if you were to swim westward along the shore, you'd come across some reef without much coral or seaweed growth, some reef rubble, an area of coral heads, a region with 10 percent to 50 percent seaweed cover, a section with coralline algae (a rocky form of algae, often pink in color), and then pockets of sand.
The Web site displays coastline maps on Mac and PC platforms.
The project is a partnership of the National Oceanic and Atmospheric Administration's National Ocean Service, its Fisheries branch, the state Department of Land and Natural Resources and the University of Hawai'i Institute of Marine Biology.
It is the result of the U.S. Coral Reef Task Force recommendation that all the nation's shallow coral reef areas be mapped by 2007. There are still some Hawai'i coastal areas that are not mapped, but the ocean service expects to complete them by 2006. Meanwhile, the agency is studying more detailed mapping methods and classification systems.
