California’s Summer and Winter Coastal Upwelling Impact on the Terrestrial Ecosystem

Abstract:

The terrestrial ecosystem along the California coastal region depends on the water that winter rain and year-round fog brings. The location and strength of the North Pacific Ocean high pressure system off the California coast determine the amount of rain during winter by blocking or allowing the pass of winter storms through the region. It also determines the strength and timing of alongshore winds that drive coastal upwelling, which in turns lead to cool coastal water during the spring and summer that is closely relate to fog formation.

Timing and intensity of coastal upwelling vary year to year due to a number of climate processes impacting the high pressure system and the coastal atmospheric and ocean conditions. Notably, persistent summer upwelling varies independently from the sporadic winter/early spring upwelling events (as well as other weather patterns), and in turn they impact differently the marine and terrestrial ecosystems.

Here, we review the variability and source of variability of the North Pacific High, its impact on the upwelling conditions along the California coast, and investigate their influence on terrestrial rain and fog during winter and summer, highlighting their impact on coastal and terrestrial ecosystems.