Marine regime shifts in ocean biogeochemical models:a case study in the Gulf of Alaska

Beaulieu, Claudie, Cole, Harriet, Henson, Stephanie, Yool, Andrew, Anderson, Tom, De Mora, Lee, Buitenhuis, Erik T., Butenschön, Momme, Totterdell, Ian J. and Allen, J. Icarus (2016) Marine regime shifts in ocean biogeochemical models:a case study in the Gulf of Alaska. Biogeosciences, 13 (15). pp. 4533-4553. ISSN 1726-4189

[img]
Preview
PDF (Beaulieu16) - Published Version
Available under License Creative Commons Attribution.

Download (961kB) | Preview

Abstract

Regime shifts have been reported in many marine ecosystems, and are often expressed as an abrupt change occurring in multiple physical and biological components of the system. In the Gulf of Alaska, a regime shift in the late 1970s was observed, indicated by an abrupt increase in sea surface temperature and major shifts in the catch of many fish species. A thorough understanding of the extent and mechanisms leading to such regime shifts is challenged by data paucity in time and space. We investigate the ability of a suite of ocean biogeochemistry models of varying complexity to simulate regime shifts in the Gulf of Alaska by examining the presence of abrupt changes in time series of physical variables (sea surface temperature and mixed-layer depth), nutrients and biological variables (chlorophyll, primary productivity and plankton biomass) using change-point analysis. Our results show that some ocean biogeochemical models are capable of simulating the late 1970s shift, manifested as an abrupt increase in sea surface temperature followed by an abrupt decrease in nutrients and biological productivity. Models from low to intermediate complexity simulate an abrupt transition in the late 1970s (i.e. a significant shift from one year to the next) while the transition is smoother in higher complexity models. Our study demonstrates that ocean biogeochemical models can successfully simulate regime shifts in the Gulf of Alaska region. These models can therefore be considered useful tools to enhance our understanding of how changes in physical conditions are propagated from lower to upper trophic levels.

Item Type: Article
Faculty \ School: Faculty of Science > School of Environmental Sciences
Related URLs:
Depositing User: Pure Connector
Date Deposited: 24 Sep 2016 00:20
Last Modified: 13 Nov 2020 00:50
URI: https://ueaeprints.uea.ac.uk/id/eprint/59998
DOI: 10.5194/bg-13-4533-2016

Actions (login required)

View Item View Item