Science Center Objects

Cogswell marsh is located on the eastern side of south San Francisco Bay and covers 60 hectares. We surveyed 523 elevation points and 228 vegetation plots to determine baseline conditions of the marsh. Water level loggers deployed in 2010 were used to characterize the tidal inundation patterns throughout the year. Sediment accretion rates from soil cores near Laumeister marsh were extrapolated to Cogswell marsh and used as input for the WARMER sea-level rise response model. WARMER projects that by 2060 Cogswell marsh will be dominated by mid marsh vegetation and will transition into low marsh habitat by 2090.
 

Cogswell marsh is located on the eastern side of south San Francisco Bay and covers 60 hectares. We surveyed 523 elevation points and 228 vegetation plots to determine baseline conditions of the marsh. Water level loggers deployed in 2010 were used to characterize the tidal inundation patterns throughout the year. Sediment accretion rates from soil cores near Laumeister marsh were extrapolated to Cogswell marsh and used as input for the WARMER sea-level rise response model. WARMER projects that by 2060 Cogswell marsh will be dominated by mid marsh vegetation and will transition into low marsh habitat by 2090.
 

COGSWELL MARSH

WERC Cogswell study area
(Public domain.)
WERC Cogswell figures
The elevation histogram for Cogswell Marsh shows the marsh platform is above MHW on average (Fig. 1). Data from the vegetation surveys indicate very low species richness (Fig. 2).  Results from WARMER response model indicate that Cogswell will lose relative elevation as sea levels rise (Fig. 3). The marsh platform at Cogswell Marsh is projected to transition to low marsh habitat by 2060 and be below mean sea level by 2090 (Fig. 4). The percent of time Cogswell Marsh is inundated varies throughout the year by season, with the most inundation during the winter (Fig. 5)(Public domain.)
WERC Cogswell WARMER results
(Public domain.)

To download the Cogswell PDF Summary Report (Cogswell appendix from USGS Open-File Report Final report for sea-level rise response modeling for San Francisco Bay estuary tidal marshes):