The Southern California Climate Gradient - Desert Chaparral site is part of a series, each prefixed with "Southern California Climate Gradient", that spatially spans the major ecosystems in Southern California. These effectively create a Natural Gradient of climates. The research topics of the Desert Chaparral site represent the aggregate of "Natural Gradient" sites. The major topics are as follows: 1) Understand the short-term effects of climate variability on ecosystem physiology and ecosystem function; 2) Determine the long-term effects of climate on community composition and ecosystem function; 3) Examine the tight link between climate, ecosystem function and natural disasters in Southern California and the large socioeconomic impacts of climate change; 4) Measure the spatial and temporal variation in ecosystem function. More information and available data at http://www.ess.uci.edu/~california/ and http://ameriflux.ornl.gov/fullsiteinfo.php?sid=191