The effects of oceanic phytoplankton on biogeochemical cycling, climate change, and fisheries are not well known, due to a paucity of data on their abundances. Consequently, the National Oceanic and Atmospheric Agency (NOAA), National Aeronautics and Space Administration (NASA), and several international agencies have established high priority programs to acquire and archive chlorophyll data. These programs include both in situ and remotely-sensed data sources.
We have developed high quality data sets of ocean chlorophyll, through the blending of in situ data and remotely-sensed data. We focused on historical data from the Coastal Zone Color Scanner (CZCS) era (1978-1986), since these are the only available satellite data. Large differences are observed between the blended set and the original CZCS data set, suggesting improvement in data quality, since generally in situ data sources are considered more accurate. The methods developed here will be applicable for the future, when data from several upcoming ocean color missions may be available