Nwhi

Data on NWHI mapping since 2001 gathered

NWHI (Northwestern Howaiian Islands) is a series of small islets, atols and shallows stretching over more than 2000 km of the Pacific Sea. It stretches from Nihoa Island, north west of Kauaâi, to the Kure Atoll, north west of Midway. This islets, octopus and shores are remains of vulcanic islets, which resemble the volcanos of the main Hwaiian islets, which have dug and dug under the seas.

NWHI are unpopulated, except for a few island encampments and a small year-round Midway people. NWHI's marine life is unparalleled in that it is one of the most healthy and unspoiled marine environments and may be the last large predator-dominated marine life on the world.

The NWHI CRER (Coral Reef Reserve ) was established in 2000 and protective actions were introduced to limit some activity throughout the CRER. Every year since 2000, NWHI has conducted NWHI core research on ecosystems of reefs and CRERs. During 2001, the programme was expanded to include a remapping tool that collects single-beam bathametry, soil classifying information, soil photos and videos; in 2003, multi-beam acquisition functions were added.

IKONOS images, which can be used for biotope cartography, are available in bodies of aquatic environments less than 20 metres deep. During 10 operating hours in August 2003, the R/V AHI measured 240 sq km around Midway Island in sea levels between 15 and 250 meters; these values were paired with estimates of the depth of IKONOS images within the lake to better illustrate the entire midway atollgeology.

The rastered bathymetric files (5 metre resolution) are available for downloading. This bathymetric information is paired with back-scatter information and photo/video to analyze the midway island environment. NWHI is currently being mapped and multi-beam measurements are scheduled annually. Its shores range from 20 to 100 metres and are still largely uncharted; for example, the Neckerinsel has an uncharted area of almost 1500 square kilometres and the Gardner Bench an area of over 2200 square kilometres.

This type of flat-bed testing is very time-consuming; the average advance is about 2km2/hour. CRER, CRED and other groups working in the NWHI set their own allocation priority. Future multi-beam studies are initially scheduled in areas where the RPA limits are still imperfect, such as Kure, Pearl and Hermes and Nihoa Island.

Whenever possible, we will still gather visual verification information to deliver soil truths to the interpretation of the detail bathymetric information after its collection.