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Metadata Updated: June 15, 2024

To assess the current topography of the tidal marshes we conducted survey-grade elevation surveys at all sites between 2009 and 2013 using a Leica RX1200 Real Time Kinematic (RTK)Global Positioning System (GPS) rover (±1 cm horizontal, ±2 cm vertical accuracy; Leica Geosystems Inc., Norcross, GA; Figure 4). At sites with RTK network coverage (San Pablo, Petaluma, Pt. Mugu, and Newport), rover positions were received in real time from the Leica Smartnet system via a CDMA modem ( At sites without network coverage (Humboldt, Bolinas, Morro and Tijuana), rover positions were received in real time from a Leica GS10 antenna base station via radio link. When using the base station, we adjusted all elevation measurements using an OPUS correction ( We used the WGS84 ellipsoid model for vertical and horizontal positioning. We verified rover accuracy and precision by measuring positions at local National Geodetic Survey (NGS) benchmarks and temporary benchmarks established at each site (Table 1). Average measured vertical errors at benchmarks were 1-2 cm throughout the study, comparable to the stated error of the GPS. At each site, we surveyed marsh surface elevation along transects oriented perpendicular to the major tidal sediment source, with a survey point taken every 12.5 m; 50 m separated transect lines. We used the Geoid09 model to calculate orthometric heights from ellipsoid values (m, NAVD88; North American Vertical Datum of 1988) and projected all points to NAD83 UTM zone 10 or zone 11 using Leica GeoOffice (Leica Geosystems Inc, Norcross, GA, v. 7.0.1).We synthesized the elevation survey data to create a digital elevation model (DEM) at each site in ArcGIS 10.2.1 Spatial Analyst (ESRI 2013; Redlands, CA) with exponential ordinary kriging methods (5 x 5 mcell size) after adjusting model parameters to minimize the root-mean-square error (RMS). We used elevation models as the baseline conditions for subsequent analyses in this study including tidal inundation patterns, SLR response modeling, and mapping of sites by specific elevation (flooding) zones.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date June 15, 2024

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date June 15, 2024
Publisher Climate Adaptation Science Centers
Identifier 051010d4-a1bd-4b1c-9b51-399913fdac97
Data Last Modified 2016-03-11
Category geospatial
Public Access Level public
Bureau Code 010:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 0eb6e93c-50ee-4422-a1ee-c63e1be9f36d
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -122.693487,37.91093,-122.674716,37.924049
Source Datajson Identifier True
Source Hash 2d1e0f525489aa572c3b6e2b773fb6bcc1722fca4529726bd37c633a35d2e0b4
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -122.693487, 37.91093, -122.693487, 37.924049, -122.674716, 37.924049, -122.674716, 37.91093, -122.693487, 37.91093}

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