Predicted Nearshore Benthic Substrates of California - R7 - CDFW [ds3091]

Data shown here were gathered through a comprehensive state waters mapping program managed by the California State Coastal Conservancy, Ocean Protection Council, California Department of Fish and Wildlife, and the NOAA National Marine Sanctuary Program. The ultimate goal of this program was the creation of a high-resolution 1:24,000 scale geologic and habitat base map series covering all of California's 14,500 km2 state waters out to the 3 mile limit. The benthic substrate classifications provided here are not derived through traditional geologic interpretations, but are algorithmically defined using seafloor roughness (rugosity analysis) as a proxy for determining areas likely to consist of rocky reef with significant relief and sandy bottoms with lower relief. This method was used for the practical purposes of broadly generalizing habitats for MPA planning and expedient delivery of information to the Marine Life Protection Act (MLPA) Initiative process. For the sake of simplicity, the categories are called "hard" and "soft", however the limitations of the classification methods should be considered when using these terms. Note that results derived using the approach above may be confounded by factors including noise and artifacts from the original mapping data, steep slopes, and unusual geomorphic features. One consideration is that some areas where rocky bottom occurs may be underestimated by the "rough" category, including canyon slopes, deep water, and rock that is smooth, plateau-like, and/or lightly draped with sediment. The original resolution of the data collected was variable and should not be considered equal throughout the layer. For example, many areas but not all, include 2m resolution data, however, cell size increases proportionally with depth with some areas using up to 10m resolution in state water and 15m resolution where additional NOAA National Ocean Service data was used to fill in some areas of federal waters. In addition, areas of data gaps in the shallow "white zone" were filled using an IDW process with a power of 0.5 with 30 m pixels. The interpolation was made between linear shoreline data classified from NOAA Environmental Sensitivity Index data and the subtidal seafloor mapping data used to classify the offshore area. This version is a statewide mosaic of all data resampled at 10m. It is appropriate for cartographic use but should not be used for area calculations. A vector version at the original resolution can be downloaded with this raster through BIOS.

California Coastal and Seafloor Mapping Project, California Department of Fish and Wildlife