Smith_etal_GRL_2017_sampled_parameters.csv

Tabulated values were sampled at 1 km spaced sites along the west coast and Channel Islands of the USA. Values reflect inverse distance weighted averages of terrestrial catchment characteristics of the nearest 40 streams, with an exponent of distance of 0.5. We used published bathymetry (NOAA bathymetric coverage, https://maps.ngdc.noaa.gov/viewers/bathymetry/, supplemented by California Seafloor Mapping Project coverage, http://seafloor.otterlabs.org/SFMLwebDATA_SURVEYMAP.htm) to identify canyon heads and slope edge gullies. Canyons are indicated when a sampling site intersects a 5 km buffer surrounding identified canyon heads. Coastal drainage basins >0.1 km² were delineated and topographically characterized (slope, relief, area) using the 1/3 second USGS National Elevation Dataset (https://catalog.data.gov/dataset/usgs-national-elevation-dataset-ned). These data were used with bedrock geology and precipitation to calculate bedload yields. The percentage of bedrock lithologies in each catchment was characterized using state bedrock geologic maps, and annual precipitation was obtained from the PRISM Climate Group, Oregon State University, http://prism.oregonstate.edu/.