Patrick L. Barnard
Daniel Hoover
2009
A seamless, high-resolution, coastal digital elevation model (DEM) for Southern California
Version 1.0, October 1, 2009
ARC Ascii Grids (for conversion to raster grids)
https://pubs.usgs.gov/ds/487/
A seamless, three-meter digital elevation model (DEM) was constructed for the entire Southern
California coastal zone, extending 473 km from Point Conception to the Mexican border. The goal
was to integrate the most recent, high-resolution datasets available (for example, Light Detection
and Ranging (Lidar) topography, multibeam and single beam sonar bathymetry, and Interferometric Synthetic
Aperture Radar (IfSAR) topography) into a continuous surface from at least the 20-m isobath to the +20-m
elevation contour.
This dataset was produced to provide critical boundary conditions (bathymetry and topography) for a
modeling effort designed to predict the impacts of severe winter storms on the Southern California coast
(Barnard and others, 2009). The hazards model, run in real-time or with prescribed scenarios, incorporates
atmospheric information (wind and pressure fields) with a suite of state-of-the-art physical process models
(tide, surge, and wave) to enable detailed prediction of water levels, run-up, wave heights, and currents.
Research-grade predictions of coastal flooding, inundation, erosion, and cliff failure are also included.
The DEM was constructed to define with the general shape of nearshore, beach and cliff surfaces as
accurately as possible, with less emphasis on fine-scale (meters to tens of meters) variations in elevation
and on bathymetry inside harbors. As a result this DEM should not be used for navigation purposes.
Any use of trade, product, or firm names is for descriptive purposes
only and does not imply endorsement by the
U.S. Government.
Although this Federal Geographic Data Committee-compliant metadata
file is intended to document the data set in nonproprietary form,
as well as in ArcInfo format, this metadata file may include some
ArcInfo-specific terminology.
http://walrus.wr.usgs.gov/coastal_processes/socalhazards/
1996
2008
topography at time underlying data set was collected (See Source Information)
None planned
-120.511
-117.033
34.494
32.518
None
digital elvation model
coastal
beaches
ocean
hazards
ISO 19115 Topic Category
elevation
geoscientificInformation
oceans
NASA Global Change Master Directory (GCMD) Keywords
OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY
OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > SEAFLOOR TOPOGRAPHY
NASA Global Change Master Directory (GCMD) Instrument Keywords
IfSAR > Interferometric Synthetic Aperture Radar
LIDAR > Light Detection and Ranging
MSBS > Multibeam Swath Bathymetry System
NASA Global Change Master Directory (GCMD) Platform Keywords
DEM > Digital Elevation Model
Geographic Names Information System
Southern California
California
USA
GEOnet Names Server
north Pacific Ocean
None
Majority of data (that is, Lidar, multibeam bathymetry, IfSAR) derived from topographic/bathymetry data
collected at 1-3 m horizontal resolution,with vertical uncertainty at time of data collection
ranging from 10 cm to 1 m, Use at greater scales not advised. See full Data Series report for more
information:
Barnard, P.L. and Hoover, D., 2009.
A seamless, high-resolution, coastal digital elevation model (DEM) for southern California:
U.S. Geological Survey Data Series 487, 8 p., [https://pubs.usgs.gov/ds/487/].
This information is not intended for navigational
purposes.
Patrick L. Barnard
United States Geological Survey (USGS)
Coastal and Marine Geology (CMG)
Reserach Geologist
mailing and physical address
USGS, 400 Natural Bridges Drive
Santa Cruz
CA
95060
USA
(831) 427-4756
(831) 427-4748
pbarnard@usgs.gov
http://walrus.wr.usgs.gov/coastal_processes/???
preview image of report (in zip file)
GIF
>California State University, Monterey Bay (CSUMB) and
>Fugro Pelagos, Inc. for California State Waters Mapping Project (CSWMP)
> from Pat Iampietro;
>Fugro Pelagos, Inc. (Fugro);
>Los Angeles County
> from Drew Decker;
>National Geophysical Data Center (NGDC);
>National Oceanic and Atmospheric Administration (NOAA);
>San Diego Association of Governments (SANDAG)/Fugro;
>Scripps Institution of Oceanography (Scripps)
> from Darren Wright;
>United States Geologial Survey (USGS)
> from Pete Dartnell and from David Finlayson;
>University of Texas at Austin (UT)
> from Randy Bucciarielli and from Robert Gutierrez.
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.3.1.1850
United States Geological Survey
2009
Southern California Coastal Hazards
http://walrus.wr.usgs.gov/coastal_processes/socalhazards/
Refer to the DEM Accuracy and Limitations section in this Data Series for
an explanation of the accuracy of the identification of the entities and
assignments of values in the data set and a description of the tests used.
Refer to the DEM Construction Methods section in this Data Series for
an explanation of the fidelity of relationships in the data set and tests used.
Refer to the DEM Construction Methods section in this Data Series for
information about omissions, selection criteria, generalization, definitions used, and
other rules used to derive the data set.
Refer to the DEM Accuracy and Limitations section in this Data Series for
an explanation of the accuracy of the horizontal coordinate measurements and
a description of the tests used.
Refer to the DEM Accuracy and Limitations section in this Data Series for
an explanation of the accuracy of the vertical coordinate measurements and
a description of the tests used.
California State University, Monterey Bay
Unknown
Multibeam bathymetry
contact Pat Iampietro, <pat_iampietro@csumb.edu>
http://seafloor.csumb.edu/SFMLwebDATA.htm
digital data - raster grids or ascii xyz text files
2001
2007
ground condition
CSUMB
Provided data for coverage areas:
nearshore bathymetry, La Jolla Canyon, nearshore Santa Monica Bay, and
nearshore in Ventura County.
Fugro Pelagos, Inc. for California State Waters Mapping Project
Unknown
Multibeam bathymetry
contact Pat Iampietro, <pat_iampietro@csumb.edu>
digital data - raster grids or ascii xyz text files
2008
ground condition
Fugro for CSWMP
Provided data for coverage areas:
offshore Coal Oil and Pt. Conception region, nearshore San Diego County,
nearshore Orange County, Los Angeles Harbor, nearshore Santa Monica Bay,
west of Pt. Dume, and east of Mugu.
Fugro Pelagos, Inc.
Unknown
Scanning Hydrographic Operational Airborne Lidar Survey (SHOALS)
contact Pete Dartnell, <pdartnell@usgs.gov>
digital data - raster grids or ascii xyz text files
2002
ground condition
Fugro
Provided data for coverage area:
Orange County nearshore western half.
Los Angeles County
Unknown
Lidar (topo)
contact Drew Decker, <ddecker@usgs.gov>
digital data - raster grids or ascii xyz text files
2006
ground condition
Los Angeles County
Provided data for coverage area:
all Los Angeles County.
National Geophysical Data Center
Unknown
Regional Digital Elevation Model (DEM)
http://www.ngdc.noaa.gov/mgg/coastal/coastal.html
digital data - raster grids or ascii xyz text files
Unknown
ground condition
NGDC
Provided data for coverage area:
all Southern California.
National Oceanic and Atmospheric Administration
Unknown
IfSAR, LIDAR (topo), multibeam bathymetry, and tsunami DEM
http://maps.csc.noaa.gov/dataviewer/viewer.html
digital data - raster grids or ascii xyz text files
1998
2003
ground condition
NOAA
Provided data for coverage areas:
all land, Mugu to Los Angeles County border, El Segundo nearshore,
Los Angeles Harbor, and Santa Barbara Channel
San Diego Association of Governments
Unknown
Multibeam bathymetry
contact Pete Dartnell, <pdartnell@usgs.gov>
digital data - raster grids or ascii xyz text files
2001
ground condition
SANDAG/Fugro
Provided data for coverage area:
inside 40 m isobath, San Diego County.
Scripps Institution of Oceanography
Unknown
ATV/PWC and CHARTS Lidar (Topo+Bathy)
contact Darren Wright, Scripps
http://cdip.ucsd.edu/SCBPS/?nav=data
digital data - raster grids or ascii xyz text files
2004
2009
ground condition
Scripps
Provided data for coverage areas:
Camp Pendleton, Cardiff, Torrey Pines, Imperial Beach, and most of San Diego County
United States Geologial Survey
Unknown
Z-2-06-SC, Z-1-07-SC, and S-8-08-SC multibeam bathymetry; S-V2-06-CA and S-V1-07-CA personal watercraft (PWC)
contact Patrick Barnard <pbarnard@usgs.gov>; Pete Dartnell, <pdartnell@usgs.gov>;
and David Finlayson, <dfinlayson@usgs.gov>
http://walrus.wr.usgs.gov/infobank/z/z206sc/html/z-2-06-sc.meta.html
http://walrus.wr.usgs.gov/infobank/z/z107sc/html/z-1-07-sc.meta.html
http://walrus.wr.usgs.gov/infobank/s/s808sc/html/s-8-08-sc.meta.html
http://walrus.wr.usgs.gov/infobank/s/sv206ca/html/s-v2-06-ca.meta.html
http://walrus.wr.usgs.gov/infobank/s/sv107ca/html/s-v1-07-ca.meta.html
digital data - raster grids or ascii xyz text files
1996
2008
ground condition
USGS
Provided data for coverage areas:
East of Gaviota, El Capitan, nearshore Carpinteria, Coal Oil, nearshore Gaviota and Naples,
Tijuana Estuary, Los Angeles and San Diego County, Orange County nearshore western half,
Ventura nearshore, nearshore east Carpinteria plus offshore bathymetry
for Santa Barbara Channel, Ventura region, Mugu region, Rincon region, Carpinteria, and
Goleta.
University of Texas at Austin
Unknown
Lidar (topo)
contact Randy Bucciarielli, <rbucciarelli@ucsd.edu>, and Robert Gutierrez, UT
http://maps.csc.noaa.gov/dataviewer/viewer.html
digital data - raster grids or ascii xyz text files
2005
2007
ground condition
UT
Provided data for coverage areas:
San Diego County, Orange County, Seal Beach to Long Beach, and
Point Conception to Point Mugu coastal strip.
>ESRI geoprocessing history
> Tool location:
> C:\ArcGIS\ArcToolbox\Toolboxes\Spatial Analyst Tools.tbx\ExtractByMask
> Command issued:
> ExtractByMask la1unclip DEMFullCoverageAreas\la1_fullcoveragearea D:\HazardsModel\DEM\FinalDEMs\CoastalHighRes\DEMs_3m\FinalMosaics\la1final
> _________________
> Spatial data description
> Raster dataset information
> Raster format: GRID
> SDTS raster type: Grid Cell
> Number of raster bands: 1
> Raster properties
> Origin location: Upper Left
> Has pyramids: FALSE
> Has colormap: FALSE
> Data compression type: Default
> Display type: matrix values
> Cell information
> Number of cells on x-axis: 7317
> Number of cells on y-axis: 8160
> Number of cells on z-axis: 1
> Number of bits per cell: 32
> Cell Size
> X distance: 3.000000
> Y distance: 3.000000
> _________________
20090615
154257
>(Summary) Performed by Patrick Barnard and Dan Hoover:
>
> ArcGIS was the primary software used for DEM construction.
> For each individual DEM, the native data sets were mosaiced into a single grid
> to preserve the original surfaces as closely as possible.
> Prior to mosaicing, data sets were gridded and/or resampled to 3 m resolution (if necessary),
> and their spatial extents modified according to the following guidelines:
>
> 1. Data sets of comparable quality
> (for example, overlapping multibeam data) or
> where relative data quality could not be determined
> (for example, older multibeam and recent but lower resolution personal-watercraft data,
> were not clipped.
> In these instances the overlapping regions were blended together
> using the Blend algorithm in the Mosaic to New Raster tool in Arc Toolbox.
>
> 2. In overlapping regions where the quality of one data set was clearly inferior
> to the other (for example, IfSAR overlapping with Lidar),
> the spatial extent of the inferior data set was clipped so there was minimal overlap,
> typically about ~10-30 m, with the superior data set.
> The overlapping regions then were smoothed together using the Blend algorithm.
> This range of overlap was found to be the most efficient
> for ensuring a smooth transition between data sets
> while minimizing the use the of data set of inferior quality.
2009
>(Detailed) Performed by Patrick Barnard and Dan Hoover:
>
> 1. Divide study area into ~10 km alongshore segments
> A. Define DEM coverage area/polygon that extends
> ~10 km alongshore from -20 m isobath to 20 m topographic contour or
> 750 m from back beach, whichever is longer
> B. Ensure that adjacent DEM coverage areas overlap by ~ 250 m
> C. Cut off DEMs at county boundaries with ~500 m overlap
>
> 2. Acquire most recent or highest resolution data sets in DEM coverage areas (Figure 2)
> A. Lidar
> B. Multibeam bathymetry
> C. Local high-resolution beach topography (usually ATV-acquired) and
> nearshore bathymetry (usually PWC-acquired)
> D. IfSAR
>
> 3. Fill gaps with older/lower resolution data sets
> A. Lidar (for example, NOAA Digital Coast, 1997-98)
> B. NOAA lower-resolution multibeam (for example, Los Angeles Harbor entrance)
> C. Regional, lower resolution DEMs (for example, NOAA Santa Barbara Channel 10-m DEM)
>
> 4. Convert all data sets into identical
> horizontal coordinate system, vertical datum, and grid resolution
> A. Horizontal coordinate system: UTM NAD 83 Zone 11 North
> B. Vertical Datum: NAVD88
> -If different (usually MLLW), convert using local NOAA tide station information
> (http://tidesandcurrents.noaa.gov/) based on survey metadata
> C. Grid resolution: 3 m
> -If already gridded at higher or < 10 m resolution,
> resample to 3 m using bilinear interpolation
> -If already gridded at resolution of =10 m, export as xyz,
> re-import as xyz, create TIN (triangular irregular network),
> create 3 m grid from TIN using linear interpolation of the TIN triangles,
> clip to survey extent
> -If ungridded then for:
> -Lidar (topography):
> 3 m grid using natural neighbor interpolation
> to preserve abrupt elevation changes (for example, beaches backed by cliffs)
> -Multibeam:
> 3 m grid using inverse distance weighting using "Average Gridder"
> in Fledermaus- ideal for data sets > 10 million points
> -Lower resolution surveys (for example, personal waterscraft-collected bathymetry):
> create TIN from points then convert to 3 m grid
> using linear interpolation of the TIN triangles
>
> 5. Clip data sets to DEM/coverage needs, if necessary
> A. Useful for data management and processing efficiency
> B. Necessary for very large data sets, such as county-wide IfSAR or
> very large Lidar data sets (for example, Los Angeles County)
> C. Clip ocean and waves from topographic Lidar and IfSAR
> -Clip water level by determining sea level at time of survey then
> using "Extract by Attributes" tool in Arc Toolbox
> -Clip wave crests manually with mask
>
> 6. Manage overlapping data sets
> A. Data sets allowed to overlap extensively only if they are of comparable quality,
> otherwise minimal (~10-30 m) overlap to ensure smooth DEM transitions
> B. Clip IfSAR data (lower quality)
> to minimal overlap with topographic Lidar (better quality)
> C. Clip low-resolution data sets gridded to higher resolution,
> such as Personal Watercraft data and regional DEMs,
> to minimal overlap with adjacent high-resolution data sets
> (usually multibeam and topographic Lidar)
> D. Extensive overlap between adjacent Lidar and multibeam data sets rare but
> allowed as quality is comparable
>
> 7. Fill in data gaps between high-resolution data sets
> A. If no high-resolution data exist between the 10 m isobath and coastal Lidar, or
> in protected harbors/embayments or other areas where interpolation
> from surrounding data sets will create a surface unlikely
> to accurately reflect actual bathymetry/topography,
> fill in with regional DEMs or other low-resolution data sets.
> Otherwise interpolate across gaps.
> -Filling in with regional DEMs/other low-resolution data:
> -Clip best available regional DEM to fill gap with minimal overlap (~10-30 m)
> with adjacent high resolution data sets
> -Export clipped grid as xyz, reimport as points, create tin,
> create 3 m grid from tin, clip to gap extent
> -Interpolation
> -Create preliminary DEM using Mosaic tool with the following settings:
> Coordinate System: UTM Zone 11 North
> Pixel Type: 32_Bit_Float
> Cell Size: 3
> Mosaic Method: Blend
> Mosaic Color Map: Last
> -Create mask of data gap(s) to fill with minimal overlap
> with preliminary DEM surface
> -Clip preliminary DEM with mask, export clipped grid as xyz,
> reimport as points, create tin, create 3 m grid from tin, clip to gap extent
>
> 8. Compile final DEMs
> A. Load all data sets for DEM
> B. Verify all significant data gaps filled (few missing cells OK) in DEM coverage area
> C. Build DEM using Mosaic to New Raster tool in ArcGIS with same setting as in Item #7
> D. Clip DEM to DEM coverage area
> E. Create contours and plot cross-shore profiles to verify data quality and consistency
2009
First draft of metadata created by Patrick Barnard using .txt template
20090924
Raster
Grid Cell
8160
7317
1
Universal Transverse Mercator
11
0.999600
-117.000000
0.000000
500000.000000
0.000000
row and column
3.000000
3.000000
meters
>Horizontal coordinate system
> Projected coordinate system name: NAD_1983_UTM_Zone_11N
> Geographic coordinate system name: GCS_North_American_1983
>Bounding coordinates
> Horizontal
> In decimal degrees
> West: -118.239274
> East: -117.999280
> North: 33.918479
> South: 33.695581
> In projected or local coordinates
> Left: 385440.225447
> Right: 407391.225447
> Top: 3753569.022415
> Bottom: 3729089.022415
row and column
3.000000
3.000000
meters
North American Datum of 1983
Geodetic Reference System 80
6378137.000000
298.257222
United States Geological Survey (USGS)
Coastal and Marine Geology (CMG)
Patrick L Barnard
Research Geologist
mailing and physical address
USGS, 400 Natural Bridges Drive
Santa Cruz
CA
95060
USA
(831) 427-4756
(831) 427-4748
pbarnard@usgs.gov
U.S. Geological Survey Data Series 487
Please recognize the U.S. Geological Survey (USGS) as the source of
this information.
Although these data have been used by the U.S. Geological Survey,
U.S. Department of the Interior, no warranty expressed or implied
is made by the U.S. Geological Survey as to the accuracy of the
data.
The act of distribution shall not constitute any such warranty,
and no responsibility is assumed by the U.S. Geological Survey in
the use of this data, software, or related materials.
Compressed file including Arcinfo grid and metadata.
7.2
Arcinfo grid
windows winzip or unix gunzip
0.526
https://pubs.usgs.gov/ds/487/
none
20100127
20100127
United States Geological Survey (USGS)
Coastal and Marine Geology (CMG)
Patrick L Barnard
Research Geologist
mailing and physical address
USGS, 400 Natural Bridges Drive
Santa Cruz
CA
95060
USA
(831) 427-4756
(831) 427-4748
pbarnard@usgs.gov
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
none
none
http://www.esri.com/metadata/esriprof80.html
ESRI Metadata Profile