The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport
We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model. We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass co...
Published in: | Global Biogeochemical Cycles |
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Online Access: | https://doi.org/10.1029/2019GB006385 |
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ftncar:oai:drupal-site.org:articles_23491 2024-04-28T07:56:54+00:00 The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport Rohr, Tyler (author) Harrison, Cheryl (author) Long, Matthew C. (author) Gaube, Peter (author) Doney, Scott C. (author) 2020-06-02 https://doi.org/10.1029/2019GB006385 en eng Global Biogeochemical Cycles--Global Biogeochem. Cycles--0886-6236--1944-9224 articles:23491 ark:/85065/d7bz698g doi:10.1029/2019GB006385 Copyright 2020 American Geophysical Union. article Text 2020 ftncar https://doi.org/10.1029/2019GB006385 2024-04-04T17:33:50Z We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model. We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass concentrations, growth rates, and physical transport. On average, cyclones induce negative division rate anomalies that drive negative net population growth rate anomalies, reduce dilution across shallower mixed layers, and advect biomass anomalously downward via eddy-induced Ekman pumping. The opposite is true in anticyclones. Lateral transport is dominated by eddy stirring rather than eddy trapping. The net effect on anomalous biomass can exceed 10-20% of background levels at the regional scale, consistent with observations. Moreover, we find a strong seasonality in the sign and magnitude of regional anomalies and the processes that drive them. The most dramatic seasonal cycle is found in the South Pacific Antarctic Circumpolar Current, where physical and biological processes dominate at different times, modifying biomass in different directions throughout the year. Here, in cyclones, during winter, anomalously shallow mixed layer depths first drive positive surface biomass anomalies via reduced dilution, and later drive positive depth-integrated biomass anomalies via reduced light limitation. During spring, reduced iron availability and elevated grazing rates suppress net population growth rates and drive the largest annual negative surface and depth-integrated biomass anomalies. During summer and fall, lateral stirring and eddy-induced Ekman pumping create small negative surface anomalies but positive depth-integrated anomalies. The same mechanisms drive biomass anomalies in the opposite direction in anticyclones. 1852977 Article in Journal/Newspaper Antarc* Antarctic Southern Ocean OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) Global Biogeochemical Cycles 34 6 |
institution |
Open Polar |
collection |
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) |
op_collection_id |
ftncar |
language |
English |
description |
We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model. We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass concentrations, growth rates, and physical transport. On average, cyclones induce negative division rate anomalies that drive negative net population growth rate anomalies, reduce dilution across shallower mixed layers, and advect biomass anomalously downward via eddy-induced Ekman pumping. The opposite is true in anticyclones. Lateral transport is dominated by eddy stirring rather than eddy trapping. The net effect on anomalous biomass can exceed 10-20% of background levels at the regional scale, consistent with observations. Moreover, we find a strong seasonality in the sign and magnitude of regional anomalies and the processes that drive them. The most dramatic seasonal cycle is found in the South Pacific Antarctic Circumpolar Current, where physical and biological processes dominate at different times, modifying biomass in different directions throughout the year. Here, in cyclones, during winter, anomalously shallow mixed layer depths first drive positive surface biomass anomalies via reduced dilution, and later drive positive depth-integrated biomass anomalies via reduced light limitation. During spring, reduced iron availability and elevated grazing rates suppress net population growth rates and drive the largest annual negative surface and depth-integrated biomass anomalies. During summer and fall, lateral stirring and eddy-induced Ekman pumping create small negative surface anomalies but positive depth-integrated anomalies. The same mechanisms drive biomass anomalies in the opposite direction in anticyclones. 1852977 |
author2 |
Rohr, Tyler (author) Harrison, Cheryl (author) Long, Matthew C. (author) Gaube, Peter (author) Doney, Scott C. (author) |
format |
Article in Journal/Newspaper |
title |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
spellingShingle |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
title_short |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
title_full |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
title_fullStr |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
title_full_unstemmed |
The simulated biological response to Southern Ocean eddies via biological rate modification and physical transport |
title_sort |
simulated biological response to southern ocean eddies via biological rate modification and physical transport |
publishDate |
2020 |
url |
https://doi.org/10.1029/2019GB006385 |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
Global Biogeochemical Cycles--Global Biogeochem. Cycles--0886-6236--1944-9224 articles:23491 ark:/85065/d7bz698g doi:10.1029/2019GB006385 |
op_rights |
Copyright 2020 American Geophysical Union. |
op_doi |
https://doi.org/10.1029/2019GB006385 |
container_title |
Global Biogeochemical Cycles |
container_volume |
34 |
container_issue |
6 |
_version_ |
1797585499206975488 |