Patrick W. Limber
Patrick L. Barnard
Andrea C. O'Neill
Amy C. Foxgrover
20221205
Northern California 3.2 projections of coastal cliff retreat due to 21st century sea-level
Coastal cliff retreat projections in shapefiles
data release
DOI:10.5066/P9048D1S
Pacific Coastal and Marine Science Center Santa Cruz, California
U.S. Geological Survey
https://doi.org/10.5066/P9048D1S
https://www.sciencebase.gov/catalog/item/636d7473d34ed907bf6ba1fc
Patrick L. Barnard
Li H. Erikson
Amy C. Foxgrover
Patrick W. Limber
Andrea C. O'Neill
Jennifer A. Thomas
Sean F. Vitousek
2022
Coastal Storm Modeling System (CoSMoS) for northern California 3.2
version 1b
modeling results presented in various formats
data release
DOI:10.5066/P9048D1S
Pacific Coastal and Marine Science Center, Santa Cruz, California
U.S. Geological Survey
https://doi.org/10.5066/P9048D1S
This dataset contains projections of coastal cliff retreat and associated uncertainty across Northern California for future scenarios of sea-level rise (SLR) to include 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, and 500 centimeters (cm) of SLR by the year 2100 and cover coastline from the Golden Gate Bridge to the California-Oregon state border. Present-day cliff-edge positions used as the baseline for projections are also included. Projections were made using numerical models and field observations such as historical cliff retreat rate, nearshore slope, coastal cliff height, and mean annual wave power, as part of Coastal Storm Modeling System (CoSMoS). See cited references and methods for more detail.
These data provide an estimate of potential coastal cliff retreat and erosion in response to sea-level rise during the 21st century, to help identify and assess possible areas of vulnerability. Uncertainty should be included in any assessment or analysis. Data are intended for policy makers, resource managers, science researchers, and students. These data can be used with geographic information systems or other software to help 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/.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
2022
year of publication
None planned
-124.4448
-122.4774
41.9985
37.8921
USGS Metadata Identifier
USGS:636d7473d34ed907bf6ba1fc
Data Categories for Marine Planning
Physical Habitats and Geomorphology
Global Change Master Directory (GCMD)
Hazards Planning
Ocean Waves
Erosion
Sea Level Rise
Extreme Weather
USGS Thesaurus
Climate Change
Storms
mathematical modeling
effects of climate change
earth sciences
ISO 19115 Topic Category
Oceans
ClimatologyMeteorologyAtmosphere
Marine Realms Information Bank (MRIB) keywords
sea level change
waves
coastal erosion
None
U.S. Geological Survey
USGS
Coastal and Marine Hazards and Resources Program
CMHRP
Pacific Coastal and Marine Science Center
PCMSC
Geographic Names Information System
State of California
None
Northern California
Northern California Coast
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.
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
California
95060-5792
USA
831-427-4747
pcmsc_data@usgs.gov
Limber, P.W.
Barnard, P.L.
Vitousek, S.
Erikson, L.H.
2018
A model ensemble for projecting multi-decadal coastal cliff retreat during the 21st century
Limber, P.W., Barnard, P.L., Vitousek, S., and Erikson, L.H, 2018, A model ensemble for projecting multi-decadal coastal cliff retreat during the 21st century: Journal of Geophysical Research--Earth Surface, v. 123, p.1566-1589, https://doi.org/10.1029/2017JF004401.
https://doi.org/10.1029/2017JF004401
Attribute values are estimates of cliff retreat and uncertainty due to plausible future sea-level rise scenarios in the future and therefore cannot be cross-checked with observations, because observations do not exist. The projections were generated using established numerical methods and are in line with previous work by researchers. While the latest cliff edge data was used in the modeling, the general lack of extensive historical data and difficulty in identifying active cliff edges in many locations (for example, obscured by vegetation, or topographic slope showing no inflection) led to high uncertainty in some areas. Uncertainty bands derived from the ensemble numerical models take into account the positional accuracy of the geospatial data used to calibrate the numerical models, statistical agreement between different models used to generate the projections, and variations of the projections caused by varying initial conditions (a sensitivity analysis). Including uncertainty is recommended for use in any analysis.
Data have undergone QA/QC and fall within expected/reasonable ranges.
These geospatial projections are complete. Users are advised to read the rest of the metadata record and references carefully for additional details.
A formal accuracy assessment of the projections was conducted for each model output location. The horizontal model accuracy (or uncertainty) for each model output point is included within this geospatial dataset and was determined at the 95 percent confidence level.
N/A
U.S. Geological Survey
2017
2016 USGS west coast lidar DEM (WA, OR, CA)
online
NOAA Digital Coast
https://coast.noaa.gov/htdata/raster2/elevation/West_Coast_El_Nino_DEM_2016_6260/
online
20020101
20160528
data collection dates
Lidar
A continuous sea cliff edge was digitized from the 2002, 2010, and 2016 lidar DEM. The cliff edge was then used 1) to calculate long-term cliff retreat rates and 2) as the baseline from which future projections of cliff retreat were made.
Hapke, C.
Reid, D.
Borelli, M.
2007
The National Assessment of Shoreline Change; a GIS compilation of vector cliff edges and associated cliff erosion data for the California coast
online
U.S. Geological Survey
https://pubs.usgs.gov/of/2007/1112/
online
19290101
19500101
dates of valid data
TSHEET
Cliff edges were used to calculate historical long-term rates of cliff retreat
U.S. Geological Survey
2020
Coastal National Elevation Database (CoNED) Project - Topobathymetric Digital Elevation Model (TBDEM) for Northern California
online
U.S. Geological Survey
https://topotools.cr.usgs.gov/topobathy_viewer/
online
2020
Publication date
DEM
Topobathymetric Digital Elevation Model (TBDEM) for Northern California
California Coastal Commission
2005
California Coastal Armoring Database
online
California Coastal Commission
https://gis.cnra.ca.gov/arcgis/rest/services/Ocean/CSMW_Coastal_Structures/MapServer/
online
2005
Publication date
Armor database
Database of coastal armoring locations across California
Google Earth
2021
Aerial imagery for Northern California
online
Google Earth
https://earth.google.com/
online viewer
20050101
20210401
dates of valid data
aerial imagery
Recent aerial imagery to verify armoring locations
Foxgrover, A.C.
Erikson, L.H.
O'Neill, A.C.
2022
Northern California cross-shore transects for CoSMoS 3.2
online
U.S. Geological Survey
https://doi.org/10.5066/P9048D1S
online dataset
2022
publication date
CSTs
cross-short transects (CSTs) used throughout study region for model setup locations
O'Neill, A.C.
Erikson, L.H.
Barnard, P.L.
2022
Nearshore total water level (TWL) proxies (2018-2100) for Northern California
online
U.S. Geological Survey
https://doi.org/10.5066/P9048D1S
online dataset
2022
publication date
nearshore wave forcing
time series of nearshore wave impacts for projections
All process steps match those outlined in Limber and others (2018); specific details for implementation in Northern California are included here. Historical sea cliff retreat rates were established using cliff edge positions from TSHEETS and Lidar datasets. In areas where sufficient data were present, all cliff edge data were used to calculate a linear regression rate. Where linear regression was not possible, end-point rates between TSHEET and the most recent lidar were used. In locations without reliable TSHEET data, end-point rates were determined between lidar datasets. Finally, for locations where no cliff edge data were available, rates from nearby transects or the nearest location with similar lithology were spatially averaged and assigned. In addition to the paucity of available data for many transects, the active cliff edge was obscured by vegetation or topographically indistinct in many locations, leading to generally higher uncertainty of cliff-top locations throughout the region.
TSHEETS
Lidar
CSTs
20201101
Historical rates
Extracted cross-shore profiles, cliff toe elevations, and beach slopes from Lidar and DEM data. Verified armoring locations with current imagery.
Lidar
DEM
Armoring database
aerial imagery
20210405
cliff profile information
Ran multi-model ensemble with nearshore wave forcing and various SLR scenarios to project future cliff positions. As described by Limber and others (2018), four ensemble members were used (Hackney, Trenhaile version 1, Trenhaile version 2, TWL models; see manuscript for more details); the Bruun model was not included for this region. Historical retreat rates, cliff toe elevation, beach slopes, and cliff height discussed above were used as inputs to the model ensemble. In much of Northern California, due to the limitations in existing data ensemble projections showed more spread compared to other locations with more observations; therefore, the weighted average used in much of Northern California was more tolerant of spread from individual ensemble members to provide better projection consistency. At headland and peninsula locations with significant projected retreat, projection lines may cross over each other. As this model does not make any assumption or statement on effectiveness of armoring or other structures, it was run in two scenarios providing end-member cases: 1) imposing projection limits where armoring features exist ("Hold the Line") and 2) letting projections proceed past armoring features ("Let it go").
Historical rates
cliff profile information
nearshore wave forcing
20210830
model output
As described in Limber and others (2018), model output and uncertainty were mapped. Visual and statistical QA/QC was performed to identify and correct data that did not meet quality control standards. Data was packaged for dissemination. Baseline cliff points used in the analysis are included for comparison (Cliff_0SLR_Baseline_pts). Projections of cliff retreat for given SLR (Cliff_ProjectionLines) and associated uncertainty (Cliff_Uncertainty) are available for both model cases (limiting projections in locations of existing coastal armoring/"Hold the Line", and letting projection proceed unhindered by armoring/"Let it Go"). All output files are zipped together.
model output
20220815
Internal USGS PID registered with PIR tool and updated the metdate for harvesting purposes. No data or metadata were changed. (scochran@usgs.gov)
20230209
Vector
GT-polygon composed of chains
28000
0.001
0.001
Decimal degrees
World Geodetic System 1984 (WGS84)
WGS84
6378137.0
298.257223563
Northern California projections of cliff retreat for 21st century (2021-2100) due to sea-level rise
Shapefiles consist of cliff retreat projections (Cliff_ProjectionLines) caused by wave impacts in different named sea-level rise (SLR) scenarios and different management options. Model case or management-case options illustrate projected retreat at impeded locations with existing armoring (HoldTheLine), or showing unimpeded retreat (LetItGo). Positions for SLRs of 25, 50, 75, 92, 100, 125, 150, 175, 200, 250, 300, and 500 cm are included.
originators at United States Geological Survey, Pacific Coastal and Marine Science Center
SLR_cm
amount of sea-level rise (SLR) for projected cliff retreat (25 cm or greater)
producer defined
25
500
cm
25
Northern California cliff retreat uncertainty
Shapefiles consists of uncertainty range polygons (Cliff_Uncertainty) for corresponding projections of cliff retreat caused by wave impacts in different named sea-level rise (SLR) scenarios and different management options. Model case or management-case options illustrate projected retreat at impeded locations with existing armoring (HoldTheLine), or showing unimpeded retreat (LetItGo). Positions for SLRs of 25, 50, 75, 92, 100, 125, 150, 175, 200, 250, 300, and 500 cm are included.
originators at United States Geological Survey, Pacific Coastal and Marine Science Center
SLR_cm
amount of SLR for given cliff retreat uncertainty (25 cm or greater)
producer defined
25
500
cm
25
Northern California cliff baseline positions
Shapefile consists of points showing baseline cliff positions (Cliff_0SLR_Baseline_pts) for model transects
originators at United States Geological Survey, Pacific Coastal and Marine Science Center
Ln_ID
transect ID number for each model output location
producer defined
8071
11589
NA
1
SLR_cm
SLR for baseline points, 0 cm
producer defined
0
0
cm
25
Projections of coastal cliff retreat for 21st century sea-level rise. The shapefiles files consist of shoreline positions changes (displayed as lines, with vertices at defined transects) caused by wave impacts in different named sea-level rise scenarios and model case/management options. Baseline cliff locations (points at each transect, for SLR 0 cm) are included for comparison. Projection files include uncertainty bands as a polygon around each projection line.
Cliff retreat projections and uncertainty are generated and shown at transects (spaced approximately 100m-300m apart alongshore, identified in whole numbers) for Northern California.
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
These data are available in shapefile formats, packaged in one zip file.
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. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Shapefile
ArcGIS 10.8.1
Esri polygon shapefiles
The .zip file includes shapefiles (point, line and polygon) for projections of coastal cliff retreat
WinZip
2.42
https://www.sciencebase.gov/catalog/file/get/636d7473d34ed907bf6ba1fc?name=Coastal_Cliff_Retreat_Projections_NorCal_CoSMoS_3-2.zip
https://www.sciencebase.gov/catalog/item/636d7473d34ed907bf6ba1fc
https://doi.org/10.5066/P9048D1S
https://www.sciencebase.gov/catalog/item/5633fea2e4b048076347f1cf
Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the data file. The second link points to the page with the data and metadata. The third link points to the landing page for all of the CoSMoS Northern California 3.2 data. The fourth link points to the community landing page for the entire CoSMoS project.
none
20230209
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
California
95060-5792
USA
831-427-4747
pcmsc_data@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998