Satellite Climatology of Chlorophyll and Sea Surface Temperature Fronts in the Northeast U.S. Large Marine Ecosystem

Kimberly J W Hyde, NOAA/NMFS, kimberly.hyde@noaa.gov (Presenting)
John E O'reilly, NOAA/NMFS, jay.oreilly@noaa.gov
Igor M Belkin, URI/Graduate School of Oceanography, ibelkin@gso.uri.edu

Satellite data from several thermal and ocean color sensors (AVHRR, SeaWiFS, MODIS-Aqua and MODIS-Terra) were processed with a newly developed algorithm to generate a climatology of chlorophyll and sea surface temperature (SST) fronts in the Northeast U.S. Large Marine Ecosystem. The main novelty is image pre-processing with context shape-preserving selective median filter iterated until convergence. When applied to chlorophyll data, the context median filter emphasizes spatial patterns peculiar to this field, namely chlorophyll enhancement associated with thermohaline fronts, and small- and meso-scale chlorophyll blooms. These patterns are modeled as ridges and peaks that are preserved and treated differently from other fronts modeled as steps or ramps. The resulting climatology of fronts is based on 10 years of chlorophyll data and 8 years of SST data. This presentation describes the main spatial patterns and temporal features, relationships between SST and chlorophyll fronts, and long-term trends of this climatology.