Kelp distribution off California

This data set delineates kelp beds (Nereocystis leutkeana and Macrocystis spp.) along the Pacific Coast of California. Multiple years of kelp mapping data for the state have been compiled into a single coastwide data set. Due to variability in oceanographic and climatic conditions, kelp bed abundance and distribution is extremely variable from year to year. Therefore kelp bed locations and extent in a particular year may not reflect current or past conditions. In addition, the methods for mapping kelp in California have changed over time. Despite these caveats, this multi-year kelp coverage can be used to identify areas that have been known to support kelp growth, and investigate general patterns of kelp distribution on a coastwide scale.California has three coastal kelp surveys. The first survey, 1989, was a coastwide survey using the same contractor and method as Washington State. Kelp canopy data from the second survey, 1999, was created from digital image processing of scanned aerial photographs. The 2002 survey was performed with a Digital Multispectral Video (DMSV) sensor and kelp beds were delineated by digital image processing techniques.