HR: 1400h
AN: OS23A-02    [Abstracts]
TI: MODIS imagery as a tool for water quality assessments in southern California coastal ocean
AU: * Nezlin, N P
EM: nikolayn@sccwrp.org
AF: Southern California Coastal Water Research Project, 3535 Harbor Blvd., Suite 110, Costa Mesa, CA 92626, United States
AU: DiGiacomo, P M
EM: paul.digiacomo@noaa.gov
AF: NOAA/NESDIS Center for Satellite Applications and Research, 5200 Auth Road, Camp Springs, MD 20746, United States
AU: Jones, B H
EM: bjones@usc.edu
AF: University of Southern California, Marine Environmental Biology, 3616 Trousdale Parkway, Los Angeles, CA 90089, United States
AU: Reifel, K M
EM: kreifel@usc.edu
AF: University of Southern California, Marine Environmental Biology, 3616 Trousdale Parkway, Los Angeles, CA 90089, United States
AU: Warrick, J A
EM: jwarrick@usgs.gov
AF: USGS Pacific Science Center, 400 Natural Bridges Drive, Santa Cruz, CA 95060, United States
AU: Johnson, S C
EM: scj_aqua@pacbell.net
AF: Aquatic Bioassay and Consulting Laboratories, 29 N Olive Street, Ventura, CA 93001, United States
AU: Mengel, M
EM: mjmengel@ocsd.com
AF: Orange County Sanitation District, 10844 Ellis Avenue, Fountain Valley, CA 92708, United States
AB: Stormwater plumes are main source of coastal pollution in southern California coastal waters. The data on surface salinity, concentrations of total suspended solids (TSS), colored dissolved organic matter (CDOM) and bacterial counts collected during the Bight'03 Regional Water Quality Program surveys in February 2004 and February-March 2005 were compared to MODIS-Aqua satellite imagery. The spectra of normalized water-leaving radiation (nLw) were different in plumes and in ambient ocean waters, enabling plumes discrimination and plume area size assessments from remotely-sensed data. The plume/ocean nLw differences (i.e., plume optical signatures) were most evident during first days after the rainstorm and less evident in the area where TSS concentration in discharged water was lower than in other regions. The accuracy of plume area assessments from satellite imagery was not high (77% on average), seemingly because of inexactitude in satellite data processing. In particular, the expected correlation between remotely-sensed CDOM absorption estimated by Lee's quasi-analytical algorithm (QAA) and CDOM concentrations in water column was often obscured by external factors including wind-driven sea state and phytoplankton blooms. Nevertheless, satellite imagery is a useful tool for estimation of the extension of polluted plumes, which is hardly achievable by contact methods.
DE: 4219 Continental shelf and slope processes (3002)
DE: 4251 Marine pollution (0345, 0478)
DE: 4275 Remote sensing and electromagnetic processes (0689, 2487, 3285, 4455, 6934)
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly