Numerical simulation of hypoxia in Hood Canal, Puget Sound

s are listed alphabetically by presenting author. Bio-physics of seabird occurrence in the northern California Current D. Ainley (Harvey & Associates), K. Dugger, R. Brodeur, D. Presser, J. Barth, S. Pierce, G. Ford, C. Tynan, L. Spear Using data from Northeast Pacific GLOBEC 2000 and 2002 process cruises, we modeled the biological and physical factors that explain seabird occurrence during the upwelling season off Oregon. Seabird densities were derived from strip censuses conducted whenever ships were underway during daylight. Explanatory variables were derived from SeaSoar and HTI (acoustic arrays), as well as fish trawls conducted along cruise tracks. In past excercises using some of these data (Ainley et al. 2005, DSR II), we explored relationships only for the 2000 cruise and only with SeaSoar and uncorrected acoustic data. The acoustic data now converted to actual biomass estimates of micronekton, along with direct results of prey availability from trawls, and for both cruises (one of which occurred during El Nino), should provide much greater insight into why seabirds occurred where they did and what explained variation in numbers. Numerical simulation of hypoxia in Hood Canal, Puget Sound Bohyun Bahng, Mitsuhiro Kawase, Jan Newton, Allan Devol and Wendi Ruef School of Oceanography, Box 357940, University of Washington Seattle, WA 98195-5351 [email protected] Hood Canal is one of Puget Sound sub-basins. Material exchange is mainly through the northern entrance of the Canal. Numerical modeling was applied to hindcast long-term mean seasonal variation of dissolved oxygen (DO) and a planktonic ecosystem in the Canal, with a simple nitrogen-based bio-geochemical model, coupled in a circulation model, Regional Ocean Modeling System (ROMS). Physical forcing included were seasonal climatology of salinity at the northern open boundary, seasonal climatology of river discharge at the 8 rivers. Bio-geochemical tracer boundary conditions included were seasonal climatologies of nitrate, ammonium, chlorophyll, phytoplankton and dissolved oxygen at the northern boundary. At the surface was seasonal climatology of solar radiation applied for photosynthesis. Also was seasonal climatology of wind stress applied at the surface to study wind effect. The model inputs were constructed with a set of historical monitoring, field cruise and weather station data. The results of the