Nearshore bathymetric evolution on a high-energy beach during the 2009-10 El Nino winter

Patrick L. Barnard; Daniel J. Hoover; Jeffrey A. Hansen

doi:10.1142/9789814355537_0105

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Nearshore bathymetric evolution on a high-energy beach during the 2009-10 El Nino winter

Patrick L. Barnard·Daniel J. Hoover·Jeffrey A. Hansen

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Abstract

The nearshore bathymetric evolution of a high-energy beach at the mouth of San Francisco Bay, California (USA), was tracked before, during, and after the powerful El Niño winter of 2009-10 to quantify alongshore bar formation and migration as well as the magnitude and alongshore variability of cross-shore transport. The observed deep-water winter wave energy was among the highest ever recorded in Northern California, peaking during a 7 day period in the middle of January 2010 with a mean deep-water significant wave height ( H s ) of 5.5 m, and a maximum H s = 9 m . The extreme forcing during the study period resulted in local bed level changes that approached 5 m, cross-shore bar migration of > 250 m, ~3 m alongshore trough deepening, and a net gain of ~1.6 million m 3 of sediment to the nearshore profile over the 7 km alongshore extent of the survey area, leaving beach sand levels severely depleted. The morphological evolution observed during this El Niño winter may serve as a proxy for future coastal response to climate change if current trends of increased storminess continue for the U.S. West Coast.

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Source-reported bounding extent: 37.66833156378343° to 37.779398571318765° latitude; -122.51953124999999° to -122.49721527099611° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Patrick L. Barnard, Daniel J. Hoover, Jeffrey A. Hansen. 2012-06-07. Nearshore bathymetric evolution on a high-energy beach during the 2009-10 El Nino winter. https://doi.org/10.1142/9789814355537_0105

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