As part of the Hawaii Ocean Time-series (HOT) Program, an ongoing series of oceanographic measurements is in progress in the North Pacific subtropical gyre at Station Aloha (22°45.0' N, 158°00.0' W).  One of the instruments used is an ac-9 (WET Labs, Inc.), which measures the absorption and attenuation of water at 9 wavelengths.  Concurrent measurements of conductivity, temperature, and depth are made using a CTD.  Together these instruments are slowly lowered through the water column to study oceanic properties from the surface to over 200 m depth.  These measurements are made approximately monthly.

This website describes the instruments used, deployment procedures and locations, and the resulting data.  The data from these measurements may also be downloaded from this site if desired.

Webpage by Jasmine S. Nahorniak, Oregon State University.