Spring 2008 Update: Data Sources
SST is derived by compositing data from three sources, the Advanced Very-High Resolution Radiometer onboard the Polar Orbiting Environmental Satellite (AVHRR-POES), MODIS Terra and MODIS Aqua, and represents the near-surface ocean temperature, not the temperature of the entire water column.
Daily synoptic views of surface concentrations of chlorophyll a are derived from the Sea-viewing Wide Field of View Sensors (SeaWiFS) ocean color sensor onboard the SeaStar spacecraft. Chlorophyll a is considered to be an index of the amount of phytoplankton biomass present in surface water.
Zooplankton biomass is derived from shipboard surveys of the U.S. Northeast Shelf ecosystem – these small animals link the energy produced through primary production to higher trophic levels. From 1977-1987, the MArine Resources Monitoring, Assessment, & Prediction (MARMAP) program conducted intensive surveys from Cape Hatteras, North Carolina to Nova Scotia. These efforts continued at a reduced level through the 1990s and are ongoing today as the Ecosystem Monitoring program (EcoMon). Currently, 30 plankton samples are taken 6 times a year in each of the four ecosystem subareas: Middle Atlantic Bight, Southern New England, Georges Bank, and Gulf of Maine (resulting in approximately 720 measures of zooplankton biomass annually). Zooplankton are identified to the lowest taxonomic level possible resulting in taxa specific abundances and distributions.
Long term SST were extracted from the Extended Reconstructed Sea Surface Temperature (ERSST, version 3) dataset. This dataset is based on the temperature compilation of the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) SST dataset and represents interpolation procedures that reconstructs SST fields in regions with sparse data.
Mean lengths were calculated from the NEFSC bottom trawl survey database. The lengths were averaged across all of the major species we collect and across both seasons to provide an annual snapshot of mean length of the fish community. We executed this calculation for four main ecoregions, Gulf of Maine, Georges Bank, Southern New England, and Middle Atlantic Bight.