USE OF SEAWIFS AND AVHRR TO CHARACTERIZE MOVEMENT OF PACIFIC NORTHWESTCOAST HARMFUL ALGAL BLOOMS

摘要

Satellite remote sensing data are being used to help understand the mechanism ofinitiation and movement of oceanic waters containing harmful algal blooms along thePacific Northwest Coast of Washington State. Blooms of the toxic diatom Pseudonitzschiaspp.(PN) are hypothesized to form along the Washington/British Columbiacoast in a semi-permanent eddy that forms just west of the Strait of Juan de Fuca. Thesewaters are also associated with higher levels of the toxin domoic acid (DA), produced byPN, and are known to cause closures of shellfish harvesting areas along the Washingtoncoast, frequently for an entire season. Ocean color imagery from the NASA/OrbImageSea-viewing Wide Field of View Sensor (SeaWiFS) and sea surface temperature from theAdvanced Very High Resolution Radiometer (AVHRR) are being used to track the extentand movement of the eddy. In addition, relationships between satellite imagery and insituchlorophyll concentration, PN cell numbers and DA toxin data from past researchcruises are being explored retrospectively. These data, coupled with a modeling effort,are being used to determine the scenarios that result in transport of PN cells to theWashington coast. The ultimate goal is to develop a predictive capability that willstreamline monitoring and allow for more effective management of shellfish harvesting.