San Diego County Ecosystems: The Ecological Impacts of Climate Change on a Biodiversity Hotspot
INTRODUCTION TO SAN DIEGO'S CLIMATE AND ECOSYSTEMS
by Amber D. Pairis, Udara Abeysekera, John M. Randall, Megan K. Jennings, Julie Kalansky, and Dan Cayan
T
he Mediterranean-type ecosystems of California, characterized by warm, dry summers and relatively cool, intermittantly wet winters, are some of the most ecologically diverse systems outside of the tropics (Cowling et al. 1996). The California Floristic Province (CFP), spanning from southwestern Oregon to northwestern Baja California, is largely coincident with this Mediterraneantype climate zone. The CFP is recognized as one of the
world’s biodiversity hotspots (Stein et al. 2000, Burge et al. 2016) with high species richness and diversity among both plants and animals. The focus of our study is the San Diego region’s mountains, foothills, valleys, and coastal zone. The study area encompasses a complex overlay of topography from the Pacific coast to interior mountains. The area is characterized by highly variable precipitation, strong seasonality, and coastal low clouds and fog (CLCF)
34°30'N
Total Native Species Richness 1099 - 1255 1256 - 1358 1359 - 1426 1427 - 1470 1471 - 1499 1500 - 1519 1520 - 1531 1532 - 1550 1551 - 1580 1581 - 1624 Ecoregions Additional Areas Considered
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Pacific Ocean
U.S.
- Mexico Border
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Sources: Esri, USGS, NOAA, Esri, HERE, DeLorme, MapmyIndia, © 0 12.5 25 and the GIS 50 OpenStreetMap contributors, userKilometers community 117°30'W
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FIGURE 1: Map of overall species richness for all plant and vertebrate faunal taxa. Ecoregional subsection boundaries are displayed to identify how richness varies in San Diego’s different ecosystems.
