Rainfall and Salinity Effects on Future Pacific Climate Change
Abstract Most climate models simulate an intensified eastern equatorial Pacific warming in response to increasing greenhouse gas concentrations. So far, the proposed mechanisms have focused on thermodynamic aspects such as the spatial inhomogeneity of evaporative feedbacks, and future increases in u...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Wiley
2023-08-01
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| Series: | Earth's Future |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2022EF003457 |
| _version_ | 1797733443844440064 |
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| author | Hyuna Kim Axel Timmermann Sun‐Seon Lee Fabian Schloesser |
| author_facet | Hyuna Kim Axel Timmermann Sun‐Seon Lee Fabian Schloesser |
| author_sort | Hyuna Kim |
| collection | DOAJ |
| description | Abstract Most climate models simulate an intensified eastern equatorial Pacific warming in response to increasing greenhouse gas concentrations. So far, the proposed mechanisms have focused on thermodynamic aspects such as the spatial inhomogeneity of evaporative feedbacks, and future increases in upper ocean thermal stratification, partly intensified by projected Walker circulation weakening. Here we show, using earth system model freshwater perturbation experiments, that the simulated future rainfall intensification along the equator plays an important role in tropical climate change. Associated negative equatorial salinity anomalies of about −0.6 permil, which are very similar to the projected late 21st century salinity anomalies in CMIP6 SSP585 scenario, strengthen upper ocean stratification in the Pacific which leads to a flattening of the thermocline, shoaling of the equatorial undercurrent, and major shifts in tropical ocean dynamics. The resulting eastern basin equatorial warming also contributes to a marked weakening of the Pacific Walker circulation. Our analysis illustrates the importance of rainfall and salinity changes in the tropical climate system with relevance for understanding both, patterns of future climate change as well as the El Niño Southern Oscillation phenomenon. |
| first_indexed | 2024-03-12T12:29:13Z |
| format | Article |
| id | doaj.art-f17d2d4c92e4404e8203565754610cbb |
| institution | Directory Open Access Journal |
| issn | 2328-4277 |
| language | English |
| last_indexed | 2024-03-12T12:29:13Z |
| publishDate | 2023-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Earth's Future |
| spelling | doaj.art-f17d2d4c92e4404e8203565754610cbb2023-08-29T18:52:31ZengWileyEarth's Future2328-42772023-08-01118n/an/a10.1029/2022EF003457Rainfall and Salinity Effects on Future Pacific Climate ChangeHyuna Kim0Axel Timmermann1Sun‐Seon Lee2Fabian Schloesser3Center for Climate Physics Institute for Basic Science (IBS) Busan Republic of KoreaCenter for Climate Physics Institute for Basic Science (IBS) Busan Republic of KoreaCenter for Climate Physics Institute for Basic Science (IBS) Busan Republic of KoreaInternational Pacific Research Center University of Hawaii at Manoa Honolulu HI USAAbstract Most climate models simulate an intensified eastern equatorial Pacific warming in response to increasing greenhouse gas concentrations. So far, the proposed mechanisms have focused on thermodynamic aspects such as the spatial inhomogeneity of evaporative feedbacks, and future increases in upper ocean thermal stratification, partly intensified by projected Walker circulation weakening. Here we show, using earth system model freshwater perturbation experiments, that the simulated future rainfall intensification along the equator plays an important role in tropical climate change. Associated negative equatorial salinity anomalies of about −0.6 permil, which are very similar to the projected late 21st century salinity anomalies in CMIP6 SSP585 scenario, strengthen upper ocean stratification in the Pacific which leads to a flattening of the thermocline, shoaling of the equatorial undercurrent, and major shifts in tropical ocean dynamics. The resulting eastern basin equatorial warming also contributes to a marked weakening of the Pacific Walker circulation. Our analysis illustrates the importance of rainfall and salinity changes in the tropical climate system with relevance for understanding both, patterns of future climate change as well as the El Niño Southern Oscillation phenomenon.https://doi.org/10.1029/2022EF003457rainfalltropical Pacificsalinity effectclimate feedbackPacific walker circulationclimate change |
| spellingShingle | Hyuna Kim Axel Timmermann Sun‐Seon Lee Fabian Schloesser Rainfall and Salinity Effects on Future Pacific Climate Change Earth's Future rainfall tropical Pacific salinity effect climate feedback Pacific walker circulation climate change |
| title | Rainfall and Salinity Effects on Future Pacific Climate Change |
| title_full | Rainfall and Salinity Effects on Future Pacific Climate Change |
| title_fullStr | Rainfall and Salinity Effects on Future Pacific Climate Change |
| title_full_unstemmed | Rainfall and Salinity Effects on Future Pacific Climate Change |
| title_short | Rainfall and Salinity Effects on Future Pacific Climate Change |
| title_sort | rainfall and salinity effects on future pacific climate change |
| topic | rainfall tropical Pacific salinity effect climate feedback Pacific walker circulation climate change |
| url | https://doi.org/10.1029/2022EF003457 |
| work_keys_str_mv | AT hyunakim rainfallandsalinityeffectsonfuturepacificclimatechange AT axeltimmermann rainfallandsalinityeffectsonfuturepacificclimatechange AT sunseonlee rainfallandsalinityeffectsonfuturepacificclimatechange AT fabianschloesser rainfallandsalinityeffectsonfuturepacificclimatechange |