Downscaling climate change models to local site conditions: San Diego National Wildlife Refuge Complex

Metadata Updated: May 11, 2018

Executive Summary Southern California tidal marshes have been affected by coastal development and urbanization.Over the past 150 years, dredging and filling operations have resulted in the loss of 42% of SanDiego Bay’s historic shallow subtidal habitat, 84% of its intertidal mudflat habitat, and 70% of itssalt marsh habitat (San Diego Bay NWR CCP 2006). The San Diego National Wildlife RefugeComplex, administered by the U.S. Fish & Wildlife Service, was established in 1972 with the goalof protecting rare birds, migratory species and marsh dependent species of southern California. Our study follows a bottom-up approach to evaluating local sea-level rise effects on tidal marshes.The study was conducted at the parcel scale while being relevant for landscape scalemanagement. The objectives of this study were to: (1) develop high resolution digital elevationmodels (DEMs) for the salt marshes of the San Diego Refuge Complex, (2) monitor water levelsand tidal cycles to assess parcel level inundation patterns and capture extreme water events, (3)inventory vegetation species composition and relationship to elevation and tidal ranges, and (4)develop sea-level rise marsh response models for Tijuana Slough marsh. This report contains baseline elevation, tidal range, and plant community results for the San DiegoBay National Wildlife Refuge Complex: Tijuana Slough National Wildlife Refuge (Tijuana),Sweetwater marsh unit (Sweetwater), South San Diego Bay unit (South Bay), and Seal BeachNational Wildlife Refuge (Seal Beach). A total of 12,013 elevation points were measured across all sites between September andDecember 2011 with a Real Time Kinematic (RTK) GPS (± 2.5 cm vertical accuracy). 11,470elevation data points were used to create digital elevation models (DEMs) for the marsh platforms.Elevation for all sites fell within a large range of 1.4 m (NAVD88) with 84% between 1.2 and 2.6 m.Across all sites mean elevation was 0.46 m (SD = 0.65) above mean high water (MHW). Vegetation was sampled in 0.25-m2 quadrats at 2,855 locations across all sites. Distinct zonationin plant communities was observed in relation to elevation and tidal datum (MHW), because plantsare typically restricted by their inundation tolerance and soil salinities. Batis maritima andSarcocornia pacifica were the two most common species across all site; B. maritima occurred at65% of the sampled quadrats, and S. pacifica occurred at 63% of all surveyed quadrats. Water level loggers were deployed at all sites (n=8) starting in September 2011. Water level datafrom September 2011 to January 2013 are presented in this report. Peak tide levels for this timeperiod were averaged for each site to produce site-specific tidal datums for mean tide level (MTL),mean high water (MHW), and mean higher high water (MHHW). We used the Marsh Equilibrium Model (MEM) to project initial estimates of marsh elevation changeunder sea-level rise (SLR) scenarios to 2100 for Tijuana marsh. Results from the SLR responsemodeling for the north arm of the Tijuana marsh indicated that relative elevation will decreasethrough 2100 under mid (+93 cm) and high (+166 cm) SLR scenarios, but it will maintain elevationunder the low (+44 cm) SLR scenario. MEM results were categorized by low, mid, and high marsh habitat types. Results showed that lowmarsh will decrease dramatically after 2030 under low SLR rates, whereas under mid SLR, lowmarsh will increase through 2090 before beginning to decrease. Under high SLR rates, low marshincreases to 2060 and then decreases until it disappears in 2090. Mid and high marsh will remainconstant under low SLR rates. However, mid marsh decreases after 2060 and disappears after2100 under mid SLR rates. Under high SLR rates, mid marsh decreases after 2030 and disappearsafter 2080. High marsh disappears after 2070 under mid SLR, and disappears after 2050 with highSLR. Ongoing work is underway to improve SLR marsh response modeling at Tijuana, Seal Beach andSweetwater. This w

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.

Downloads & Resources




Metadata Created Date December 2, 2017
Metadata Updated Date May 11, 2018

Metadata Source

Harvested from DOI CKAN Harvest Source

Additional Metadata

Resource Type Dataset
Metadata Created Date December 2, 2017
Metadata Updated Date May 11, 2018
Publisher Fish and Wildlife Service
Unique Identifier FWS_ServCat_43163
Brent Frakes
Maintainer Email
Public Access Level public
Bureau Code "010:18"
Metadata Context
Metadata Catalog ID C:\Program Files (x86)\FWS\DataStore\Application\OpenData\FWS_ServCat_v1_1.json
Schema Version
Catalog Describedby
Data Quality true
Extras Rollup {"harvest_source_id": "9364572a-43e2-4cb5-a0ee-589c8af0e137", "issued": "2013-01-01", "resource-type": "Dataset", "references": "\"\"", "source_hash": "3947d7dda280cbfd4836370b8caf351aa639a497", "accessLevel": "public", "theme": "\"Unpublished Report\"", "spatial": "-118.0893,32.53622,-116.7879,33.75274", "programCode": "\"010:094\", \"010:028\"", "catalog_@context": "", "catalog_describedBy": "", "harvest_source_title": "FWS-servecat", "source_schema_version": "1.1", "catalog_conformsTo": "", "bureauCode": "\"010:18\"", "landingPage": "", "harvest_object_id": "cb83cf0e-3fa5-47cf-b40a-ee37afec5b34", "publisher": "Fish and Wildlife Service", "extras_rollup": "{\"harvest_source_id\": \"9364572a-43e2-4cb5-a0ee-589c8af0e137\", \"issued\": \"2013-01-01\", \"resource-type\": \"Dataset\", \"references\": \"\\\"\\\"\", \"source_hash\": \"3947d7dda280cbfd4836370b8caf351aa639a497\", \"accessLevel\": \"public\", \"theme\": \"\\\"Unpublished Report\\\"\", \"spatial\": \"-118.0893,32.53622,-116.7879,33.75274\", \"programCode\": \"\\\"010:094\\\", \\\"010:028\\\"\", \"catalog_@context\": \"\", \"catalog_describedBy\": \"\", \"harvest_source_title\": \"FWS-servecat\", \"source_schema_version\": \"1.1\", \"catalog_conformsTo\": \"\", \"bureauCode\": \"\\\"010:18\\\"\", \"landingPage\": \"\", \"harvest_object_id\": \"cb83cf0e-3fa5-47cf-b40a-ee37afec5b34\", \"publisher\": \"Fish and Wildlife Service\", \"modified\": \"2013-01-01\", \"source_datajson_identifier\": \"true\", \"catalog_@id\": \"C:\\\\Program Files (x86)\\\\FWS\\\\DataStore\\\\Application\\\\OpenData\\\\FWS_ServCat_v1_1.json\", \"dataQuality\": \"true\", \"identifier\": \"FWS_ServCat_43163\"}", "modified": "2013-01-01", "source_datajson_identifier": "true", "catalog_@id": "C:\\Program Files (x86)\\FWS\\DataStore\\Application\\OpenData\\FWS_ServCat_v1_1.json", "dataQuality": "true", "identifier": "FWS_ServCat_43163"}
Harvest Object Id cb83cf0e-3fa5-47cf-b40a-ee37afec5b34
Harvest Source Id 9364572a-43e2-4cb5-a0ee-589c8af0e137
Harvest Source Title FWS-servecat
Data First Published 2013-01-01
Homepage URL
Data Last Modified 2013-01-01
Program Code "010:094", "010:028"
Related Documents ""
Source Datajson Identifier true
Source Hash 3947d7dda280cbfd4836370b8caf351aa639a497
Source Schema Version 1.1
Spatial -118.0893,32.53622,-116.7879,33.75274
Category "Unpublished Report"

Didn't find what you're looking for? Suggest a dataset here.