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Distance to Nearest Roads (Meters): San Francisco Bay Area, California, 2011

Author(s):
, , , and
Description:
This raster dataset depicts National Overview Road Metrics - Euclidean Distance (NORM-ED) for the nine county San Francisco Bay Area Region, California and is intended for use in analyses of land surface conditions at multiple scales, particularly with application to the effects of roads on ecology, watershed quality, wildlife habitat, and enjoyment of roadless areas. These data are intended for geographic display at national levels and for large regional areas. The data should be displayed at scales appropriate for 1:100,000 scale data. This dataset was developed to describe the extent and configuration of the spaces between roads. The metric is straight-line (Euclidean) distance, in units of meters, to the nearest road. The value for any point estimates the largest radius of a circle, centered at that point, that contains no roads. The accuracy of the estimate is limited by the accuracy of the source data, both in terms of roads depicted and their positions. NORM-ED considers all roads to be equal, regardless of road surface, width, and traffic volume. The dataset from which NORM-ED was built contains features ranging from interstate highways to jeep tracks, although not necessarily with equal detail or reliability in all areas. The full-resolution dataset provides distance-to-road (DTR) values on a 30 meter grid, using an equal area projection. Values can be aggregated statistically by averaging, for example, over areas of the user's choice and results are mathematically valid. NORM-ED can be used, therefore, to calculate comparable average DTR values for Bay Area counties, watersheds, ecoregions or any other area of interest. This layer is part of the Conservation Lands Network regional biodiversity GIS database.This dataset was developed/compiled for use in the San Francisco Bay Area Upland Habitat Goals Project, a Project used to identify a Conservation Lands Network (CLN) for biodiversity preservation to inform conservation investments and lasting cooperative conservation partnerships. The Conservation Lands Network GIS Database is the primary output of the Project. The data depicts the spatially explicit CLN that is recommended for the nine county San Francisco Bay Area Region, California.
Publisher:
Bay Area Open Space Council
Place(s):
San Francisco Bay Area (Calif.), Alameda County (Calif.), Contra Costa County (Calif.), Marin County (Calif.), Napa County (Calif.), San Francisco County (Calif.), San Mateo County (Calif.), Santa Clara County (Calif.), Solano County (Calif.), and Sonoma County (Calif.)
Subject(s):
Wildland-urban interface, Metropolitan areas, Cities and towns, Roads, Streets, Imagery and Base Maps, and Transportation
Year:
2011
Held by:
Stanford
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