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USGS · 70174923

Heat wave brings an unprecedented red tide to San Francisco Bay

James E. Cloern·Tara S. Schraga·Cary B. Lopez
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Abstract

An exceptional red tide in San Francisco Bay was observed on 8 September 2004. The red tide had chlorophyll concentrations approaching 200 mg/m 3 (Figure 1) in red/purple surface streaks containing high abundances of the dinoflagellate Akashiwo sanguinea. Red tides and harmful algal blooms (HABs) are common features of coastal ecosystems, and their growing frequency is a suspected outcome of coastal eutrophication. However, the authors have never observed a dinoflagellate bloom of this scale during 28 years of sampling in the nutrient-rich San Francisco Bay. Phytoplankton biomass along this transect is typically <5mg Chla/m 3 , and has never exceeded 21 mg Chla/m 3 during summer-autumn.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 37.421435292172944° to 38.151837403006766° latitude; -122.52639770507812° to -121.93450927734375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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James E. Cloern, Tara S. Schraga, Cary B. Lopez. 2011-06-03. Heat wave brings an unprecedented red tide to San Francisco Bay. https://doi.org/10.1029/2005eo070003

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