Ocean Convective Available Potential Energy. Part I: Concept and Calculation
Thermobaric convection (type II convection) and thermobaric cabbeling (type III convection) might substantially contribute to vertical mixing, vertical heat transport, and deep-water formation in the World Ocean. However, the extent of this contribution remains poorly constrained. The concept of oce...
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ftcaltechauth:oai:authors.library.caltech.edu:b6hw7-6nm93 2024-06-23T07:57:24+00:00 Ocean Convective Available Potential Energy. Part I: Concept and Calculation Su, Zhan Ingersoll, Andrew P. Stewart, Andrew L. Thompson, Andrew F. 2016-04 https://doi.org/10.1175/JPO-D-14-0155.1 unknown American Meteorological Society https://doi.org/10.1175/JPO-D-14-0155.1 oai:authors.library.caltech.edu:b6hw7-6nm93 eprintid:66427 resolverid:CaltechAUTHORS:20160422-152511486 info:eu-repo/semantics/openAccess Other Journal of Physical Oceanography, 46(4), 1081-1096, (2016-04) Circulation/ Dynamics Conditional instability Convection Deep convection Diapycnal mixing Energy transport Fluxes info:eu-repo/semantics/article 2016 ftcaltechauth https://doi.org/10.1175/JPO-D-14-0155.1 2024-06-12T06:27:06Z Thermobaric convection (type II convection) and thermobaric cabbeling (type III convection) might substantially contribute to vertical mixing, vertical heat transport, and deep-water formation in the World Ocean. However, the extent of this contribution remains poorly constrained. The concept of ocean convective available potential energy (OCAPE), the thermobaric energy source for type II and type III convection, is introduced to improve the diagnosis and prediction of these convection events. OCAPE is analogous to atmospheric CAPE, which is a key energy source for atmospheric moist convection and has long been used to forecast moist convection. OCAPE is the potential energy (PE) stored in an ocean column arising from thermobaricity, defined as the difference between the PE of the ocean column and its minimum possible PE under adiabatic vertical parcel rearrangements. An ocean column may be stably stratified and still have nonzero OCAPE. The authors present an efficient strategy for computing OCAPE accurately for any given column of seawater. They further derive analytical expressions for OCAPE for approximately two-layer ocean columns that are widely observed in polar oceans. This elucidates the dependence of OCAPE on key physical parameters. Hydrographic profiles from the winter Weddell Sea are shown to contain OCAPE (0.001–0.01 J kg^(−1)), and scaling analysis suggests that OCAPE may be substantially enhanced by wintertime surface buoyancy loss. The release of this OCAPE may substantially contribute to the kinetic energy of deep convection in polar oceans. © 2016 American Meteorological Society. Manuscript received 1 August 2014, in final form 11 January 2016, published online 23 March, 2016. Z.S.'s and A.P.I.'s research was supported by NSF Award AST-1109299. A.L.S.'s research was supported by the University of California, Los Angeles. A.F.T.'s research was supported by NSF Award OCE-1235488. The author gratefully acknowledges the helpful comments from two anonymous reviewers. Published - ... Article in Journal/Newspaper Weddell Sea Caltech Authors (California Institute of Technology) Weddell Weddell Sea Journal of Physical Oceanography 46 4 1081 1096 |
institution |
Open Polar |
collection |
Caltech Authors (California Institute of Technology) |
op_collection_id |
ftcaltechauth |
language |
unknown |
topic |
Circulation/ Dynamics Conditional instability Convection Deep convection Diapycnal mixing Energy transport Fluxes |
spellingShingle |
Circulation/ Dynamics Conditional instability Convection Deep convection Diapycnal mixing Energy transport Fluxes Su, Zhan Ingersoll, Andrew P. Stewart, Andrew L. Thompson, Andrew F. Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
topic_facet |
Circulation/ Dynamics Conditional instability Convection Deep convection Diapycnal mixing Energy transport Fluxes |
description |
Thermobaric convection (type II convection) and thermobaric cabbeling (type III convection) might substantially contribute to vertical mixing, vertical heat transport, and deep-water formation in the World Ocean. However, the extent of this contribution remains poorly constrained. The concept of ocean convective available potential energy (OCAPE), the thermobaric energy source for type II and type III convection, is introduced to improve the diagnosis and prediction of these convection events. OCAPE is analogous to atmospheric CAPE, which is a key energy source for atmospheric moist convection and has long been used to forecast moist convection. OCAPE is the potential energy (PE) stored in an ocean column arising from thermobaricity, defined as the difference between the PE of the ocean column and its minimum possible PE under adiabatic vertical parcel rearrangements. An ocean column may be stably stratified and still have nonzero OCAPE. The authors present an efficient strategy for computing OCAPE accurately for any given column of seawater. They further derive analytical expressions for OCAPE for approximately two-layer ocean columns that are widely observed in polar oceans. This elucidates the dependence of OCAPE on key physical parameters. Hydrographic profiles from the winter Weddell Sea are shown to contain OCAPE (0.001–0.01 J kg^(−1)), and scaling analysis suggests that OCAPE may be substantially enhanced by wintertime surface buoyancy loss. The release of this OCAPE may substantially contribute to the kinetic energy of deep convection in polar oceans. © 2016 American Meteorological Society. Manuscript received 1 August 2014, in final form 11 January 2016, published online 23 March, 2016. Z.S.'s and A.P.I.'s research was supported by NSF Award AST-1109299. A.L.S.'s research was supported by the University of California, Los Angeles. A.F.T.'s research was supported by NSF Award OCE-1235488. The author gratefully acknowledges the helpful comments from two anonymous reviewers. Published - ... |
format |
Article in Journal/Newspaper |
author |
Su, Zhan Ingersoll, Andrew P. Stewart, Andrew L. Thompson, Andrew F. |
author_facet |
Su, Zhan Ingersoll, Andrew P. Stewart, Andrew L. Thompson, Andrew F. |
author_sort |
Su, Zhan |
title |
Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
title_short |
Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
title_full |
Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
title_fullStr |
Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
title_full_unstemmed |
Ocean Convective Available Potential Energy. Part I: Concept and Calculation |
title_sort |
ocean convective available potential energy. part i: concept and calculation |
publisher |
American Meteorological Society |
publishDate |
2016 |
url |
https://doi.org/10.1175/JPO-D-14-0155.1 |
geographic |
Weddell Weddell Sea |
geographic_facet |
Weddell Weddell Sea |
genre |
Weddell Sea |
genre_facet |
Weddell Sea |
op_source |
Journal of Physical Oceanography, 46(4), 1081-1096, (2016-04) |
op_relation |
https://doi.org/10.1175/JPO-D-14-0155.1 oai:authors.library.caltech.edu:b6hw7-6nm93 eprintid:66427 resolverid:CaltechAUTHORS:20160422-152511486 |
op_rights |
info:eu-repo/semantics/openAccess Other |
op_doi |
https://doi.org/10.1175/JPO-D-14-0155.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
46 |
container_issue |
4 |
container_start_page |
1081 |
op_container_end_page |
1096 |
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1802651022447869952 |