Patrick Barnard
Li Erikson
Amy Foxgrover
Andrea O'Neill
Liv Herdman
2017
CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 water-level projections: 100-year storm in Los Angeles County
Total water level projection data in GeoTIFF format
data release
DOI:10.5066/F7T151Q4
Pacific Coastal and Marine Science Center Santa Cruz, California
U.S. Geological Survey, Coastal and Marine Geology
https://doi.org/10.5066/F7T151Q4
Patrick L Barnard
Li H Erikson
Amy C Foxgrover
Patrick W Limber
Andrea C O'Neill
Sean Vitousek
2018
Coastal Storm Modeling System (CoSMoS) for Southern California, v3.0, Phase 2
Digital
data release
doi:10.5066/F7T151Q4
Pacific Coastal and Marine Science Center, Santa Cruz, California
U.S. Geological Survey
https://doi.org/10.5066/F7T151Q4
Projected Hazard: Model-derived total water levels (in meters) for the given storm condition and sea-level rise (SLR) scenario.
Model Summary: The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. CoSMoS v3.0 for Southern California shows projections for future climate scenarios (sea-level rise and storms) to provide emergency responders and coastal planners with critical storm-hazards information that can be used to increase public safety, mitigate physical damages, and more effectively manage and allocate resources within complex coastal settings.
Phase 2 data for Southern California include flood-hazard information for the coast from the border of Mexico to Pt. Conception. Several changes from Phase 1 projections are reflected in many areas; please read the model summary and inspect output carefully. Data are complete for the information presented.
Details: Model background: The CoSMoS model comprises three tiers. Tier I consists of one Delft3D hydrodynamics FLOW grid for computation of tides, water level variations, flows, and currents and one SWAN grid for computation of wave generation and propagation across the continental shelf. The FLOW and SWAN models are two-way coupled so that tidal currents are accounted for in wave propagation and growth and conversely, so that orbital velocities generated by waves impart changes on tidal currents. The Tier I SWAN and FLOW models consist of identical structured curvilinear grids that extend from far offshore to the shore and range in resolution from 0.5 km in the offshore to 0.2 km in the nearshore. Spatially varying astronomic tidal amplitudes and phases and steric rises in water levels due to large-scale effects (for example, a prolonged rise in sea level) are applied along all open boundaries of the Tier I FLOW grid. Winds (split into eastward and northward components) and sea-level pressure (SLP) fields from CaRD10 (Dr. Dan Cayan, Scripps Institute of Oceanography, Los Angeles, California, written commun., 2014) that vary in both space and time are applied to all grid cells at each model time-step. Deep-water wave conditions, applied at the open boundaries of the Tier I SWAN model runs, were projected for the 21st century Representative Concentration Pathway (RCP) 4.5 climate scenario (2011-2100) using the WaveWatch III numerical wave model (Tolman and others, 2002) and 3-hourly winds from the GFDL-ESM2M Global Climate Model (GCM).
Tier II provides higher resolution near the shore and in areas that require greater resolution of physical processes (such as bays, harbors, and estuaries). A single nested outer grid and multiple two-way coupled domain decomposition (DD) structured grids allow for local grid refinement and higher resolution where needed. Tier II was segmented into 11 sections along the Southern California Bight, to reduce computation time and complete runs within computational limitations.
Water-level and Neumann time-series, extracted from Tier I simulations, are applied to the shore-parallel and lateral open boundaries of each Tier II sub-model outer grid respectively. Several of the sub-models proved to be unstable with lateral Neumann boundaries; for those cases one or both of the lateral boundaries were converted to water-level time-series or left unassigned. The open-boundary time-series are extracted from completed Tier I simulations so that there is no communication from Tier II to Tier I. Because this one-way nesting could produce erroneous results near the boundaries of Tier II and because data near any model boundary are always suspect, Tier II sub-model extents were designed to overlap in the along-coast direction. In the landward direction, Tier II DD grids extend to the 10-m topographic contour; exceptions exist where channels (such as the Los Angeles River) or other low-lying regions extend very far inland. Space- and time-varying wind and SLP fields, identical to those used in Tier I simulations, are applied to all Tier II DD grids to allow for wind-setup and local inverse barometer effects (IBE, rise or depression of water levels in response to atmospheric pressure gradients).
A total of 42 time-series fluvial discharges are included in the Tier II FLOW domains in an effort to simulate exacerbated flooding caused by backflow at the confluence of high river seaward flows and elevated coastal surge levels migrating inland. Time-varying fluvial discharges are applied either at the closed boundaries or distributed as point sources within the relevant model domains.
Wave computations are accomplished with the SWAN model using two grids for each Tier II sub-model: one larger grid covering the same area as the outer FLOW grid and a second finer resolution two-way coupled nearshore nested grid. The nearshore grid extends from approximately 800-1,000 m water depth up to 8-10 m elevations onshore. The landward extension is included to allow for wave computations of the higher SLR scenarios. Time- and space-varying 2D wave spectra extracted from previously completed Tier I simulations are applied approximately every kilometer along the open boundaries of the outer Tier II sub-model SWAN grids. The same space- and time-varying wind fields used in Tier I simulations are also applied to both Tier II SWAN grids to allow for computation of local wave generation.
Tier III for the entire Southern California Bight consists of 4,802 cross-shore transects (CST) spaced approximately 100 m apart in the along-shore direction. The profiles extend from the -15 m isobath to at least 10 m above NAVD88. The CSTs are truncated for cases where a lagoon or other waterway exists on the landward end of the profile. Time-varying water levels and wave parameters (significant wave heights, Hs; peak periods, Tp; and peak incident wave directions, Dp), extracted from Tier II grid cells that coincide with the seaward end of the CSTs, are applied at the open boundary of each CST. The XBeach model is run in a hydrostatic (no vertical pressure gradients) mode including event-based morphodynamic change. Wave propagation, two-way wave-current interaction, water-level variations, and wave runup are computed at each transect.
XBeach simulations are included in the CoSMoS model to account for infragravity waves that can significantly extend the reach of wave runup (Roelvink and others, 2009) compared to short-wave incident waves. The U.S. west coast is particularly susceptible to infragravity waves at the shore due to breaking of long-period swell waves (Tp > 15).
Resulting water levels (WLs) from both Delft3D (high interest bays and marshes) and open-coast XBeach (CSTs) were spatially combined and interpolated to a 10 m grid. These WL elevations are differenced from the originating 2 m digital elevation model (DEM) to determine final flooding extent and depth of flooding.
Events: The model system is run for pre-determined scenarios of interest such as the 1-yr or 100-yr storm event in combination with sea-level rise. Storms are first identified from time-series of total water level proxies (TWLpx) at the shore. TWLpx are computed for the majority of the 21st century (2010-2100), assuming a linear super-position of the major processes that contribute to the overall total water level. TWLpx time-series are then evaluated for extreme events, which define the boundary conditions for subsequent modeling with CoSMoS. Multiple 100-yr events are determined (varying Hs, Tp, Dp) and used for multiple model runs to better account for regional and directional flooding affects. Model results are combined and compiled into scenario-specific composites of flood projection.
Digital Elevation Model (DEM): Our seamless, topobathymetric digital elevation model (DEM) was based largely upon the Coastal California TopoBathy Merge Project DEM, with some modifications performed by the USGS Earth Resources Observation and Science (EROS) Center to incorporate the most recent, high-resolution topographic and bathymetric datasets available. Topography is derived from bare-earth light detection and ranging (lidar) data collected in 2009-2011 for the CA Coastal Conservancy Lidar Project and bathymetry from 2009-2010 bathymetric lidar as well as acoustic multi- and single-beam data collected primarily between 2001 and 2013. The DEM was constructed to define the shape of nearshore, beach, and cliff surfaces as accurately as possible, utilizing dozens of bathymetric and topographic data sets. These data were used to populate the majority of the Tier I and II grids. To describe and include impacts from long-term shoreline evolution, including cumulative storm activity, seasonal trends, ENSO, and SLR, the DEM was modified for each SLR scenario. Long-term shoreline (Vitousek and Barnard, 2015) and cliff (Limber and others, 2015) erosion projections were efficiently combined along the cross-shore transects to evolve the shore-normal profiles. Elevation changes from the profiles were spatially-merged for a cohesive, 3D depiction of coastal evolution used to modify the DEM. These data are used to generate initial profiles of the 4,802 CSTs used for Phase 2 Tier III XBeach modeling and determining final projected flood depths in each SLR scenario. All data are referenced to NAD83 horizontal datum and NAVD88 vertical datum. Data for Tiers II and III are projected in UTM, zone 11.
Outputs include: Projected water levels for the storm and sea-level rise scenario indicated. Data correspond to the near-shore region including areas vulnerable to coastal flooding due to storm surge, sea-level anomalies, tide elevation, and wave run-up during the same storm and sea-level rise simulation.
References Cited: Howell, S., Smith-Konter, B., Frazer, N., Tong, X., and Sandwell, D., 2016, The vertical fingerprint of earthquake cycle loading in southern California: Nature Geoscience, v. 9, p. 611-614, doi:10.1038/ngeo2741.
Limber, P., Barnard, P.L. and Hapke., C., 2015, Towards projecting the retreat of California’s coastal cliffs during the 21st Century: in, Wang, P., Rosati, J.D., and Cheng, J., (eds.), The Proceedings of the Coastal Sediments: 2015, World Scientific, 14 p., doi:10.1142/9789814689977_0245
Roelvink, J.A., Reniers, A., van Dongeren, A.R., van Thiel de Vries, J., McCall, R., and Lescinski, J., 2009, Modeling storm impacts on beaches, dunes and barrier islands: Coastal Engineering, v. 56, p. 1,133–1,152, doi:10.1016/j.coastaleng.2009.08.006.
Tolman, H.L., Balasubramaniyan, B., Burroughs, L.D., Chalikov, D.V., Chao, Y.Y., Chen H.S., Gerald, V.M., 2002, Development and implementation of wind generated ocean surface wave models at NCEP: Weather and Forecasting, v. 17, p. 311-333.
Vitousek, S. and Barnard, P.L., 2015, A non-linear, implicit one-line model to predict long-term shoreline change: in, Wang, P., Rosati, J.D., and Cheng, J., (eds.), The Proceedings of the Coastal Sediments: 2015, World Scientific, 14 p., doi:10.1142/9789814689977_0215.
These data are intended for policy makers, resource managers, science researchers, students, and the general public. These data can be used with geographic information systems or other software to identify and assess possible areas of vulnerability. These data are not intended to be used for navigation.
This work is one portion of ongoing modeling efforts for California and the western United States. For more information on CoSMoS implementation, see https://walrus.wr.usgs.gov/coastal_processes/cosmos/
20151210
20170120
oldest dataset used through publication date
As needed
-120.81115722553
-116.66931152258
34.687068180405
32.546444355161
USGS Metadata Identifier
USGS:586ee9bbe4b01a71ba0bc849
Data Categories for Marine Planning
Physical Habitats and Geomorphology
Global Change Master Directory (GCMD)
Hazards Planning
Ocean Waves
Ocean Winds
Beaches
Erosion
Sea Level Rise
Storm Surge
Extreme Weather
Floods
Water Depth
USGS Thesaurus
Climate Change
Storms
Wind
Floods
Sea-level Change
ISO 19115 Topic Category
Oceans
ClimatologyMeteorologyAtmosphere
Marine Realms Information Bank (MRIB) keywords
sea level change
waves
floods
coastal erosion
Geographic Names Information System
Los Angeles County
California
None
Southern California
Southern California Bight
none
USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data.
Erikson, Li
U.S. Geological Survey, Pacific Coastal and Marine Science Center
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060-5792
USA
831-460-7563
831-427-4748
lerikson@usgs.gov
Howell, S.
Smith-Konter, B.
Frazer, N.
Tong, X.
Sandwell, D.
2016
The vertical fingerprint of earthquake cycle loading in southern California
Howell, S., Smith-Konter, B., Frazer, N., Tong, X., and Sandwell, D., 2016, The vertical fingerprint of earthquake cycle loading in southern California: Nature Geoscience, v. 9, p. 611-614, doi:10.1038/ngeo2741.
Limber, P.
Barnard, P.L.
Hapke, C.
2015
Towards projecting the retreat of California’s coastal cliffs during the 21st Century
Limber, P., Barnard, P.L. and Hapke., C., 2015, Towards projecting the retreat of California’s coastal cliffs during the 21st Century: in, Wang, P., Rosati, J.D., and Cheng, J., (eds.), The Proceedings of the Coastal Sediments: 2015, World Scientific, 14 p., doi:10.1142/9789814689977_0245
Roelvink, J.A.
Reniers, A.
van Dongeren, A.R.
van Thiel de Vries, J.
McCall, R.
Lescinski, J.
2009
Modeling storm impacts on beaches, dunes and barrier islands
Roelvink, J.A., Reniers, A., van Dongeren, A.R., van Thiel de Vries, J., McCall, R., and Lescinski, J., 2009, Modeling storm impacts on beaches, dunes and barrier islands: Coastal Engineering, v. 56, p. 1,133–1,152, doi:10.1016/j.coastaleng.2009.08.006.
Tolman, H.L.
Balasubramaniyan, B.
Burroughs, L.D.
Chalikov, D.V.
Chao, Y.Y.
Chen H.S.
Gerald, V.M.
2002
Development and implementation of wind generated ocean surface wave models at NCEP
Tolman, H.L., Balasubramaniyan, B., Burroughs, L.D., Chalikov, D.V., Chao, Y.Y., Chen H.S., Gerald, V.M., 2002, Development and implementation of wind generated ocean surface wave models at NCEP: Weather and Forecasting, v. 17, p. 311-333.
Vitousek, S.
Barnard, P.L.
2015
A non-linear, implicit one-line model to predict long-term shoreline change
Vitousek, S. and Barnard, P.L., 2015, A non-linear, implicit one-line model to predict long-term shoreline change: in, Wang, P., Rosati, J.D., and Cheng, J., (eds.), The Proceedings of the Coastal Sediments: 2015, World Scientific, 14 p., doi:10.1142/9789814689977_0215.
Attribute values are model-derived water levels due to plausible sea-level rise and future storm conditions and therefore cannot be validated against observations. The projections were generated using the latest downscaled climate projections and fluvial discharges for Southern California and calibrated hydrodynamic models.
Data have undergone quality checks and meet standards.
Dataset is considered complete for the information presented (as described in the abstract) and will be updated as necessary as improvements are developed. Users are advised to read the rest of the metadata record carefully for additional details.
Data are concurrent with topobathymetric DEM locations.
N/A
Danielson, J.
Brock, J.
Haines, J.
2015
Coastal National Elevation Database (CoNED) Applications Project: Southern California/Channel Islands Topobathymetric Elevation Model
Center for Earth Resources Observation and Science, Sioux Falls, South Dakota
U.S. Geological Survey
https://topotools.cr.usgs.gov/coned/
20100101
20121231
publication date
CoNED topobathy
online
Topobathymetric elevation information from Coastal National Elevation Database (CoNED) Applications Project: Southern California/Channel Islands Topobathymetric Elevation Model, provides fundamental elevation data for all modeling and projection processes. 2-meter resolution seamless DEM in GeoTIFF format is available from https://topotools.cr.usgs.gov/coned/
Pierce, D.
Cayan, D.
2016
Contructed Analogues Downscaled Geophysical Fluid Dynamics Laboratory (GFDL) Earth System Model 2M (ESMS2M) climate data for California
Scripps Institute of Oceanography, University of California, San Diego
Scripps Institute of Oceanography, University of California, San Diego
http://loca.ucsd.edu/
20100101
21001231
data range
GCM data
data release
Statistically downscaled GCM climate projections for North America
Obtained topobathymetric elevation data from Coastal National Elevation Database (CoNED) Applications Project (http://topotools.cr.usgs.gov/coned); used to populate Delft-3D grid bathymetry and create digital elevation model (DEM). See model summary for information on grid and model structure.
20150228
Finished initial grid and FLOW-WAVE model structure within Delft-3D. Finished test storm (January 2010 storm including tides, waves, wind, and pressure) and tide scenarios (no atmospheric forcing, FLOW only) with initial QC checks. Checks included quantitative comparisons to tide station water levels within Southern California study area and output comparisons between model versions to determine model accuracy and consistency. See model summary for information on model structure and data used.
20150501
Determined regional 100-year, 20-year, and annual storm events, as well as average conditions within Global Climate Model (GCM) data for study area. Extracted climate data from GCM for all storm events as boundary conditions for Tier I/II simulations. See model summary for information on model structure and outputs.
20160401
Began merging long-term shoreline and cliff erosion projections to create cohesive depiction of coastal evolution for each SLR scenario. Tier II model output used as conditions for XBeach projections along evolved cross-shore transects. Began post-processing Delft-3D and XBeach output within Matlab (v. 2015b) to make spatially cohesive flood projection. See model summary for information on model structure and outputs.
20160515
Metadata was modified to add or correct the Larger_Work section, and to correct the link(s) to the Methods Summary pdf so that it points to the new location of the file. No data information was changed.
20180814
Susan A Cochran
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Geologist
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060-5792
USA
(831) 460-7545
scochran@usgs.gov
Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.
20201019
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Performed minor edits to the metadata to correct typos. No data were changed
20211013
U.S. Geological Survey
Susan A. Cochran
Geologist
Mailing and Physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-7545
scochran@usgs.gov
Raster
pixel
16138
12795
Universal Transverse Mercator
11
0.999600
-100.000000
0.000000
500000.000000
0.000000
row and column
2.000000
2.000000
meters
North American Datum 1983 (NSRS2007)
Geodetic Reference System 80
6378137.000000
298.257222
NAVD88
2.0
meters
Implicit coordinate
CoSMoS v3.0 Phase 2: Los Angeles County
CoSMoS Phase 2 projections
originators at United States Geological Survey, Pacific Coastal and Marine Science Center
Projection of total water levels for given storm condition and sea-level rise (SLR) value
elevation of flood surface
model determined
0.0 m
12.50 m
meters
0.01
U.S. Geological Survey - ScienceBase
mailing and physical
Denver Federal Center, Building 810, Mail Stop 302
Denver
CO
80225
USA
1-888-275-8747
sciencebase@usgs.gov
File (CoSMoS_v3_Phase2_water_elevation.zip) contains total water level projections for sea-level rise and storm scenario indicated.
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
GeoTIFF
ArcGIS 10.2.2
Features are GeoTIFF format and are projected in UTM Zone 11 coordinates, with horizontal datum NAD83 (NSRS2007) and vertical datum NAVD88.
The .zip file includes GeoTIFF files.
WinZip
5700
https://www.sciencebase.gov/catalog/file/get/586ee9bbe4b01a71ba0bc849?community=Coastal+Storm+Modeling+System+%28CoSMoS%29
https://doi.org/10.5066/F7T151Q4
Data can be downloaded via the World Wide Web (WWW)
none
20211013
Andrea O'Neill
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Oceanographer
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060-5792
USA
831-460-7586
831-427-4748
aoneill@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998