The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks
Rapid adjustments-the response of meteorology to external forcing while sea surface temperatures (SST) and sea ice are held fixed-can affect the midlatitude circulation and contribute to long-term forced circulation responses in climate simulations. This study examines rapid adjustments in the South...
| Main Authors: | , , , , , , , , , , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
American Meteorological Society
2020
|
| _version_ | 1797069515598594048 |
|---|---|
| author | Wood, T Maycock, AC Forster, PM Richardson, TB Andrews, T Boucher, O Myhre, G Samset, BH Kirkevåg, A Lamarque, JF MüLmenstädt, J Olivié, D Takemura, T Watson-Parris, DTS |
| author_facet | Wood, T Maycock, AC Forster, PM Richardson, TB Andrews, T Boucher, O Myhre, G Samset, BH Kirkevåg, A Lamarque, JF MüLmenstädt, J Olivié, D Takemura, T Watson-Parris, DTS |
| author_sort | Wood, T |
| collection | OXFORD |
| description | Rapid adjustments-the response of meteorology to external forcing while sea surface temperatures (SST) and sea ice are held fixed-can affect the midlatitude circulation and contribute to long-term forced circulation responses in climate simulations. This study examines rapid adjustments in the Southern Hemisphere (SH) circulation using nine models from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), which perform fixed SST and coupled ocean experiments for five perturbations: a doubling of carbon dioxide (2xCO2), a tripling of methane (3xCH4), a fivefold increase in sulfate aerosol (5xSO4), a tenfold increase in black carbon aerosol (10xBC), and a 2% increase in solar constant (2%Sol). In the coupled experiments, the SH eddy-driven jet shifts poleward and strengthens for forcings that produce global warming (and vice versa for 5xSO4), with the strongest response found in austral summer. In austral winter, the responses project more strongly onto a change in jet strength. For 10xBC, which induces strong shortwave absorption, the multimodel mean (MMM) rapid adjustment in DJF jet latitude is ∼75% of the change in the coupled simulations. For the other forcings, which induce larger SST changes, the effect of SST-mediated feedbacks on the SH circulation is larger than the rapid adjustment. Nevertheless, for these perturbations the magnitude of the MMM jet shift due to the rapid adjustment is still around 20%-30% of that in the coupled experiments. The results demonstrate the need to understand the mechanisms for rapid adjustments in the midlatitude circulation, in addition to the effect of changing SSTs. |
| first_indexed | 2024-03-06T22:25:36Z |
| format | Journal article |
| id | oxford-uuid:5693dc72-fd3e-462a-9bc8-8a9afc4f452f |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T22:25:36Z |
| publishDate | 2020 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | oxford-uuid:5693dc72-fd3e-462a-9bc8-8a9afc4f452f2022-03-26T16:51:08ZThe Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacksJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5693dc72-fd3e-462a-9bc8-8a9afc4f452fEnglishSymplectic ElementsAmerican Meteorological Society2020Wood, TMaycock, ACForster, PMRichardson, TBAndrews, TBoucher, OMyhre, GSamset, BHKirkevåg, ALamarque, JFMüLmenstädt, JOlivié, DTakemura, TWatson-Parris, DTSRapid adjustments-the response of meteorology to external forcing while sea surface temperatures (SST) and sea ice are held fixed-can affect the midlatitude circulation and contribute to long-term forced circulation responses in climate simulations. This study examines rapid adjustments in the Southern Hemisphere (SH) circulation using nine models from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), which perform fixed SST and coupled ocean experiments for five perturbations: a doubling of carbon dioxide (2xCO2), a tripling of methane (3xCH4), a fivefold increase in sulfate aerosol (5xSO4), a tenfold increase in black carbon aerosol (10xBC), and a 2% increase in solar constant (2%Sol). In the coupled experiments, the SH eddy-driven jet shifts poleward and strengthens for forcings that produce global warming (and vice versa for 5xSO4), with the strongest response found in austral summer. In austral winter, the responses project more strongly onto a change in jet strength. For 10xBC, which induces strong shortwave absorption, the multimodel mean (MMM) rapid adjustment in DJF jet latitude is ∼75% of the change in the coupled simulations. For the other forcings, which induce larger SST changes, the effect of SST-mediated feedbacks on the SH circulation is larger than the rapid adjustment. Nevertheless, for these perturbations the magnitude of the MMM jet shift due to the rapid adjustment is still around 20%-30% of that in the coupled experiments. The results demonstrate the need to understand the mechanisms for rapid adjustments in the midlatitude circulation, in addition to the effect of changing SSTs. |
| spellingShingle | Wood, T Maycock, AC Forster, PM Richardson, TB Andrews, T Boucher, O Myhre, G Samset, BH Kirkevåg, A Lamarque, JF MüLmenstädt, J Olivié, D Takemura, T Watson-Parris, DTS The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title | The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title_full | The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title_fullStr | The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title_full_unstemmed | The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title_short | The Southern Hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| title_sort | southern hemisphere midlatitude circulation response to rapid adjustments and sea surface temperature driven feedbacks |
| work_keys_str_mv | AT woodt thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT maycockac thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT forsterpm thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT richardsontb thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT andrewst thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT bouchero thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT myhreg thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT samsetbh thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT kirkevaga thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT lamarquejf thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT mulmenstadtj thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT olivied thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT takemurat thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT watsonparrisdts thesouthernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT woodt southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT maycockac southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT forsterpm southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT richardsontb southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT andrewst southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT bouchero southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT myhreg southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT samsetbh southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT kirkevaga southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT lamarquejf southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT mulmenstadtj southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT olivied southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT takemurat southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks AT watsonparrisdts southernhemispheremidlatitudecirculationresponsetorapidadjustmentsandseasurfacetemperaturedrivenfeedbacks |