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Title: Response of Coastal California Hydroclimate to the Paleocene-Eocene Thermal Maximum
Abstract. The effects of anthropogenic warming on the hydroclimate of California are becoming more pronounced, with increased frequency of multi-year droughts and flooding. As a past analog for the future, the Paleocene-Eocene Thermal Maximum (PETM) is a unique natural experiment for assessing global and regional hydroclimate sensitivity to greenhouse gas warming. Globally, extensive evidence (i.e., observations, climate models with high pCO2) demonstrates hydrological intensification with significant variability from region to region (i.e., dryer or wetter, or greater frequency and/or intensity of extreme events). Central California (paleolatitude ~42° N), roughly at the boundary between dry subtropical highs and mid-latitude low pressure systems, would have been particularly susceptible to shifts in atmospheric circulation and precipitation patterns/intensity. Here, we present new observations and climate model output on regional/local hydroclimate responses in central California during PETM. Our findings based on multi-proxy evidence within the context of model output suggest a transition to an overall drier climate punctuated by increased precipitation during summer months along the central coastal California during the PETM.  more » « less
Award ID(s):
2103513
PAR ID:
10522972
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
European Geosciences Union
Date Published:
Format(s):
Medium: X
Institution:
University of California, Santa Cruz
Sponsoring Org:
National Science Foundation
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