LEAN-Corrected DEM for Suisun Marsh

Metadata Updated: November 12, 2020

Lidar-derived digital elevation models often contain a vertical bias due to vegetation. In areas with tidal influence the amount of bias can be ecologically significant, for example, by decreasing the expected inundation frequency. We generated a corrected digital elevation mode (DEM) for Suisun marsh using a modification of the Lidar Elevation Adjustment with NDVI (LEAN) technique (Buffington et al. 2016). GPS survey data (6912 points, collected across public and private land in 2018), Normalized Difference Vegetation Index (NDVI) derived from an airborne multispectral image (June 2018), a 1 m lidar DEM from September 2018, and a 1 m canopy surface model were used to generate models of predicted bias across the study domain. Due to the large differences in vegetation height and density between natural and diked wetlands, we calibrated a separate model for each cover type. The modeled predicted bias for each cover type was then subtracted from the original lidar DEM to generate a new DEM. Across all GPS points, mean initial lidar error was 22.5 cm (SD=17.5) and root-mean squared error (RMSE) was 28.5 cm. After correction with LEAN, mean error was 0 cm (SD=9.7) and RMSE was 9.7 cm, a 66 percent improvement in accuracy. Some ponds were partially flooded and had no lidar returns; to create a continuous coverage, we iteratively used the focal statistics tool with a 10 meter radius to expand the corrected elevation values into NoData areas until data gaps were covered. Large channels were masked out from the final DEM using the lidar returns and airborne imagery.

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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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Dates

Metadata Date May 13, 2019
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) July 15, 2019 (publication)
Frequency Of Update notPlanned

Metadata Source

Harvested from DOI Open Data

Additional Metadata

Resource Type Dataset
Metadata Date May 13, 2019
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) July 15, 2019 (publication)
Responsible Party U.S. Geological Survey, Western Ecological Research Center (Point of Contact)
Contact Email
Guid
Access Constraints Use Constraints: The authors of these data require that users direct any questions pertaining to appropriate use or assistance with understanding limitations and interpretation of the data to the individuals/organization listed in the Point of Contact section., Access Constraints: None. Please see 'Distribution Info' for details.
Bbox East Long -121.8325
Bbox North Lat 38.2597
Bbox South Lat 38.0362
Bbox West Long -122.1473
Coupled Resource
Frequency Of Update notPlanned
Licence 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.
Metadata Language
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True

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