NASA names co-winners for Software of the Year

SeaDAS is an outgrowth of NASA's experience with the earlier ocean color proof-of-concept mission, the Nimbus 7 Coastal Zone Color Scanner (CZCS). The CZCS data was generally unavailable to the research community and only those who developed their own processing tools could use the data. Charles McClain, currently of Science Applications International Corporation (SAIC), while at Goddard Space Flight Center (GSFC), developed such a system for CZCS analysis - SEAPAK. At the same time, McClain, Gene Carl Feldman of Goddard, and others undertook the reprocessing of the entire CZCS data set and delivery of the data set to ehe GSFC Distributed Active Archive Center (DAAC) after the sensor failed in 1986. It took five years to complete the reprocessjng and only then was the CZCS data generally available.

When the SeaWiFS mission was approved in 1991, a goal of the program was to make the data available to all researchers, not just a select science team, in a timely fashion at the highest possible quality, and to provide researchers with the tools to work with the data. McClain and Feldman were responsible for the SeaWiFS calibration and validation program and the data processing system, respectively. The restait is SeaDAS. The first beta version was released in 1994 and distributed to ocean color researchers along with simulated SeaWiFS data sets for testing and feedback, which was incorporated into the release in time for the SeaWiFS launch.

SeaWiFS - successfully launched in 1997 by McClain, Feldman, and their team - has provided continuous Earth observations through the present time. On the day of the first operational SeaWiFS data transmission the data was processed by the Special Projects Office, distributed to the community through the GSFC DAAC, and was being analy/.ed by the science community within 24 hours using SeaDAS.

The SeaDAS tool kit includes many navigation, display, analysis, and output functions. Navigation functions include data registration, map projections, coastline overlays, field data display, and latitude/longitude point location. General display functions include data scaling, color bar definition, annotation, zooming, roaming, and color palette manipulation. General analysis functions include bathymetry generation, simple arithmetic functions, contour plots, profile plots, scatter plots, and histograms.

The display and analysis modules use a commercial product, the Interactive Data Language (IDL) from Research Systems, Inc. IDL is a high-level interpretive programming language that is portable and can be used to develop GUIs, scientific graphics, or any standard statistical analysis application. The underlying satellite processing modules are independent of IDL and can be exported into other applications or used with other display and analysis packages. However, users who do know IDL can write their own IDL programs within the SeaDAS batch-scripting environment.

The most recent release of SeaDAS has been downloaded by over 500 sites in nearly 50 countries with the number of actual SeaDAS users being several times this number, because many sites support multiple researchers. This wide usage is largely due to the fact that SeaDAS is provided at no expense and runs on computer systems most users already have.