Summary

Description

On August 17, 1996, the Japanese Space Agency (NASDA - National Space Development Agency) launched the Advanced Earth Observing Satellite (ADEOS). ADEOS was in a descending, Sun synchronous orbit with a nominal equatorial crossing time of 10:30 a.m. Among the instruments carried aboard the ADEOS spacecraft was the Ocean Color and Temperature Scanner (OCTS). OCTS is an optical radiometer with 12 bands covering the visible, near infrared and thermal infrared regions. (Eight of the bands are in the VIS/NIR. These are the only bands calibrated and processed by the OBPG) OCTS has a swath width of approximately 1400 km, and a nominal nadir resolution of 700 m. The instrument operated at three tilt states (20 degrees aft, nadir and 20 degrees fore), similar to SeaWiFS. In 2001, The Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Program embarked on a collaborative effort with the National Space Development Agency (NASDA) of Japan and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Project to reprocess the entire Ocean Color and Temperature Scanner (OCTS) global area coverage (GAC) data set and make those products available to the scientific community. As part of the collaboration, NASDA provided the complete OCTS GAC Level-1A data set (November 1996 through June 1997) to NASA along with their unique expertise and analysis of the data products. (The OCTS GAC data set was created from the LAC resolution data by subsampling every 5th line and 4th pixel). NASA provided the processing expertise, methodologies and resources, and the archive and distribution support. The focus of the OCTS GAC reprocessing work was to minimize the potential processing-related differences (atmospheric correction and bio-optical algorithms) between the SeaWiFS and OCTS missions, by reprocessing the entire OCTS GAC mission archive using the same software and algorithms employed for standard SeaWiFS processing. This product contains composite eight day Level-3 binned (Equal-Area Sinusoidal grid) data products in three variants: CHL- which includes chlorophyll a, KD490 - which includes diffuse attenuation at 490nm and RRS which includes the remote sensing reflectance in the visible bands, aerosol optical depth at 862nm and aerosol angstrom parameter.