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Title: A century of change in the California Current: upwelling system amplifies acidification
Predicting the pace of acidification in the California Current System (CCS), a productive upwelling system that borders the west coast of North America, is complex because the anthropogenic contribution is intertwined with other natural sources. A central question is whether acidification in the CCS will follow the pace of increasing atmospheric CO2, or if climate effects and other biogeochemical processes will either amplify or attenuate acidification. Here, we apply the boron isotope pH proxy to cold-water orange cup corals to establish a historic level of acidification in the CCS and the Salish Sea, an associated marginal sea. Through a combination of complementary modeling and geochemical approaches, we show that the CCS and Salish Sea have experienced amplified acidification over the industrial era, driven by the interaction between anthropogenic CO2and a thermodynamic buffering effect. From this foundation, we project future acidification in the CCS under elevated CO2emissions. The projected change inpCO2over the 21stcentury will continue to outpace atmospheric CO2, posing challenges to marine ecosystems of biological, cultural, and economic importance.  more » « less
Award ID(s):
2048373
PAR ID:
10660582
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Nature
Date Published:
Journal Name:
Nature Communications
Volume:
16
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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