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Pacific Coastal and Marine Science Center

Coastal Processes

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CoSMoS 3.0: Southern California

Location map of Southern California work.

Above: Southern California data regions. [Larger version]

Flood projection map example for San Diego from Our Coast, Our Future.

Above: Example of flood projections for San Diego as viewed on Our Coast, Our Future web viewer. [Larger version]

Above: CoSMoS Research Director Dr. Patrick Barnard explains flooding projections to City of Los Angeles planners. (Photo: Holly Rindge, USC Sea Grant) [Larger version]

The Coastal Storm Modeling System for Southern California (CoSMoS 3.0) provides detailed predictions of coastal flooding due to both future sea-level rise and storms, integrated with predictions of long-term coastal evolution (beach changes and coastal cliff retreat) for the Southern California region, from Point Conception (Santa Barbara County) to Imperial Beach (San Diego County).

Explore interactive maps showing:

Southern California Regional Collaborations

CoSMoS 3.0 modeling results have been used in numerous projects throughout Southern California. Through extensive stakeholder engagement, the CoSMoS team has partnered with many local organizations to help translate CoSMoS information and make it accessible to a broad range of audiences. Key partners include:

About the CoSMoS Modeling System

CoSMoS provides a suite of 40 scenarios by combining 10 possible values for sea-level rise (0, 0.25 meter [m], 0.5 m, 0.75 m, 1.0 m, 125 m, 1.5 m. 1.75 m, 2.0 m, and 5 m) with four possible coastal storm conditions that include: daily conditions; a 1-year storm (or, 100% chance of occurring in a given year); a 20-year storm (or 5% chance); and a 100-year storm (or 1% chance).

Model enhancements for Southern California include:

  • Improved system methodology from CoSMoS 1.0 for more accurate flood projections in embayments and estuaries
  • Long-term coastal evolution projections for sandy beaches and cliffs, produced from a collection of state-of-the-art models and historical data
  • Downscaled winds from Global Climate Model (GCM) data for estimating locally generated seas and surge
  • Discharge from rivers for event response and long-term sediment supply
  • An improved baseline-elevation digital elevation model (DEM) that incorporates recent LIDAR survey

Shapefiles and associated metadata of individual flood, wave, currents and shoreline change projections for all Southern California data regions are available on the USGS ScienceBase Catalog:

Click for PDFFor a detailed technical summary of the CoSMoS modeling methodology, download CoSMoS v3.0 Southern California Bight:
Summary of Methods
(2.7 MB PDF).

In addition to the GIS shapefiles and geotiffs available on the USGS ScienceBase-Catalog, all model results are also available on the Our Coast, Our Future (OCOF) flood mapper, which provides a user-friendly web tool to review model projections. Complementary socioeconomic information is also available through the Hazards Exposure Reporting and Analytics (HERA), developed by Dr. Nathan Wood and Dr. Jeanne Jones from the USGS Western Geographic Science Center.

Email us!For questions about the modeling, please contact:
Dr. Patrick Barnard [] (Research Director) or
Dr. Li Erikson [] (Modeling Director).



Inundated areas shown should not be used for navigation, regulatory, permitting, or other legal purposes. The U.S. Geological Survey provides these data “as is” for a quick reference, emergency planning tool but assumes no legal liability or responsibility resulting from the use of this information.

The suggestions and illustrations included in these images are intended to improve coastal-flood awareness and preparedness; however, they do not guarantee the safety of an individual or structure. The contributors and sponsors of this product do not assume liability for any injury, death, property damage, or other effects of coastal flooding.

Use of trade names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey.


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Site designed, created, and maintained by: Laura Zink Torresan
Questions to: Patrick Barnard