Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes
Baroclinic eddy equilibration and the roles of different boundary layer processes in limiting the baroclinic adjustment are studied using an atmosphere–ocean thermally coupled model. Boundary layer processes not only affect the dynamical constraint of the midlatitude baroclinic eddy equilibration bu...
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| Format: | Article |
| Language: | en_US |
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American Meteorological Society
2012
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| Online Access: | http://hdl.handle.net/1721.1/73125 |
| _version_ | 1826210727878197248 |
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| author | Zhang, Yang Stone, Peter H. |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Zhang, Yang Stone, Peter H. |
| author_sort | Zhang, Yang |
| collection | MIT |
| description | Baroclinic eddy equilibration and the roles of different boundary layer processes in limiting the baroclinic adjustment are studied using an atmosphere–ocean thermally coupled model. Boundary layer processes not only affect the dynamical constraint of the midlatitude baroclinic eddy equilibration but also are important components in the underlying surface energy budget. The authors' study shows that baroclinic eddies, with the strong mixing of the surface air temperature, compete against the fast boundary layer thermal damping and enhance the meridional variation of surface sensible heat flux, acting to reduce the meridional gradient of the surface temperature. Nevertheless, the requirement of the surface energy balance indicates that strong surface baroclinicity is always maintained in response to the meridionally varying solar radiation. With the strong surface baroclinicity and the boundary layer processes, the homogenized potential vorticity (PV) suggested in the baroclinic adjustment are never observed near the surface or in the boundary layer.
Although different boundary layer processes affect baroclinic eddy equilibration differently with more dynamical feedbacks and time scales included in the coupled system, their influence in limiting the PV homogenization is more uniform compared with the previous uncoupled runs. The boundary layer PV structure is more determined by the strength of the boundary layer damping than the surface baroclinicity. Stronger boundary layer processes always prevent the lower-level PV homogenization more efficiently. Above the boundary layer, a relatively robust PV structure with homogenized PV around 600–800 hPa is obtained in all of the simulations. The detailed mechanisms through which different boundary layer processes affect the equilibration of the coupled system are discussed in this study. |
| first_indexed | 2024-09-23T14:54:14Z |
| format | Article |
| id | mit-1721.1/73125 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T14:54:14Z |
| publishDate | 2012 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | mit-1721.1/731252022-10-01T23:16:12Z Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes Zhang, Yang Stone, Peter H. Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Stone, Peter H. Baroclinic eddy equilibration and the roles of different boundary layer processes in limiting the baroclinic adjustment are studied using an atmosphere–ocean thermally coupled model. Boundary layer processes not only affect the dynamical constraint of the midlatitude baroclinic eddy equilibration but also are important components in the underlying surface energy budget. The authors' study shows that baroclinic eddies, with the strong mixing of the surface air temperature, compete against the fast boundary layer thermal damping and enhance the meridional variation of surface sensible heat flux, acting to reduce the meridional gradient of the surface temperature. Nevertheless, the requirement of the surface energy balance indicates that strong surface baroclinicity is always maintained in response to the meridionally varying solar radiation. With the strong surface baroclinicity and the boundary layer processes, the homogenized potential vorticity (PV) suggested in the baroclinic adjustment are never observed near the surface or in the boundary layer. Although different boundary layer processes affect baroclinic eddy equilibration differently with more dynamical feedbacks and time scales included in the coupled system, their influence in limiting the PV homogenization is more uniform compared with the previous uncoupled runs. The boundary layer PV structure is more determined by the strength of the boundary layer damping than the surface baroclinicity. Stronger boundary layer processes always prevent the lower-level PV homogenization more efficiently. Above the boundary layer, a relatively robust PV structure with homogenized PV around 600–800 hPa is obtained in all of the simulations. The detailed mechanisms through which different boundary layer processes affect the equilibration of the coupled system are discussed in this study. United States. Dept. of Energy (Grant DEFG02-93ER61677) United States. National Aeronautics and Space Administration (Cooperative Agreement NNG04GF12A) 2012-09-24T18:00:27Z 2012-09-24T18:00:27Z 2011-11 2011-03 Article http://purl.org/eprint/type/JournalArticle 0022-4928 1520-0469 http://hdl.handle.net/1721.1/73125 Zhang, Yang, and Peter H. Stone. “Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes.” Journal of the Atmospheric Sciences 68.11 (2011): 2710–2730. © 2011 American Meteorological Society en_US http://dx.doi.org/10.1175/jas-d-11-078.1 Journal of the Atmospheric Sciences Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Meteorological Society American Meteorological Society |
| spellingShingle | Zhang, Yang Stone, Peter H. Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title | Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title_full | Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title_fullStr | Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title_full_unstemmed | Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title_short | Baroclinic Adjustment in an Atmosphere–Ocean Thermally Coupled Model: The Role of the Boundary Layer Processes |
| title_sort | baroclinic adjustment in an atmosphere ocean thermally coupled model the role of the boundary layer processes |
| url | http://hdl.handle.net/1721.1/73125 |
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