Distribution and Cycling of Suspended Particles Inferred from Transmissivity in the Strait of Georgia, Haro Strait and Juan de Fuca Strait

Transmissometer profiles collected during quarterly cruises in 2000–03 indicate that most suspended particles in the Strait of Georgia and Juan de Fuca Strait are confined to the top and bottom of the water column. In Haro Strait, however, the particles are mixed throughout the water column by strong tidal currents, producing an estuarine turbidity maximum. The distribution and cycling of particles provide important aquatic controls for contaminant transport, photochemical reactions and photosynthesis. Particle‐associated contaminants that enter Haro Strait may remain in suspension and enter the food web at all water depths. In the autumn and sometimes in the summer, the rate of photochemical transformation of dissolved organic matter is probably higher in Juan de Fuca Strait than in the Strait of Georgia or Haro Strait, because the surface water in Juan de Fuca Strait is less turbid.