This raster dataset depicts a geography of nitrogen deposition for the nine county San Francisco Bay Area Region, California. Nitrogen deposition is the input of reactive nitrogen from the atmosphere into the biosphere as wet and dry deposition, either acidic gases and particles or acidic rain, fog and snow, respectively. An overabundance of nitrogen in the atmosphere and environment has deleterious effects on the biosphere. The source data was produced by the Center for Conservation Biology at the University of California, Riverside (UCR) and is based on a nitrogen deposition model data developed by the UCR College of Engineering Center for Environmental Research and Technology (CE-CERT). Raster values from both dry and wet nitrogen deposition models were added to provide the values stored in this raster. It represents total annual deposition of all forms of nitrogen for the calendar year 2002. These data are considered useful in studying the effect of nitrogen deposition on aspects of complex biological systems. 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.