Cold tongue/Warm pool and ENSO dynamics in the Pliocene
It has been suggested that a "permanent" El Niño climate state has existed in the warm Pliocene. One of the main pieces of evidence of such conditions is the small east-west sea surface temperature (SST) difference that is found in proxy temperature records of the equatorial Pacific. Using...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2011-08-01
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| Series: | Climate of the Past |
| Online Access: | http://www.clim-past.net/7/903/2011/cp-7-903-2011.pdf |
| _version_ | 1818610638390296576 |
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| author | A. S. von der Heydt A. Nnafie H. A. Dijkstra |
| author_facet | A. S. von der Heydt A. Nnafie H. A. Dijkstra |
| author_sort | A. S. von der Heydt |
| collection | DOAJ |
| description | It has been suggested that a "permanent" El Niño climate state has existed in the warm Pliocene. One of the main pieces of evidence of such conditions is the small east-west sea surface temperature (SST) difference that is found in proxy temperature records of the equatorial Pacific. Using a coupled version of the Zebiak-Cane model of intermediate complexity for the tropical Pacific, we study the sensitivity of the time-mean Pacific background state and El Niño/Southern Oscillation (ENSO) variability to Pliocene climate changes. The parameters varied in this sensitivity study include changes in the trade wind strength due to a reduced equator-to-pole temperature gradient, higher global mean temperatures and an open Panama gateway. All these changes lead to a westward shift of the position of the cold tongue along the equator by up to 2000 km. This result is consistent with data from the PRISM3D Pliocene SST reconstruction. Our model further suggests that ENSO variability is present in the Pliocene climate with only slight changes as compared to today. A background climate that would resemble a "permanent" El Niño with weak to no east-west temperature difference along the equator is only found for very weak trade winds which seem unrealistic for the Pliocene climate. |
| first_indexed | 2024-12-16T15:17:37Z |
| format | Article |
| id | doaj.art-cd9cd92b4da748e5973150983c3e84b1 |
| institution | Directory Open Access Journal |
| issn | 1814-9324 1814-9332 |
| language | English |
| last_indexed | 2024-12-16T15:17:37Z |
| publishDate | 2011-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Climate of the Past |
| spelling | doaj.art-cd9cd92b4da748e5973150983c3e84b12022-12-21T22:26:45ZengCopernicus PublicationsClimate of the Past1814-93241814-93322011-08-017390391510.5194/cp-7-903-2011Cold tongue/Warm pool and ENSO dynamics in the PlioceneA. S. von der HeydtA. NnafieH. A. DijkstraIt has been suggested that a "permanent" El Niño climate state has existed in the warm Pliocene. One of the main pieces of evidence of such conditions is the small east-west sea surface temperature (SST) difference that is found in proxy temperature records of the equatorial Pacific. Using a coupled version of the Zebiak-Cane model of intermediate complexity for the tropical Pacific, we study the sensitivity of the time-mean Pacific background state and El Niño/Southern Oscillation (ENSO) variability to Pliocene climate changes. The parameters varied in this sensitivity study include changes in the trade wind strength due to a reduced equator-to-pole temperature gradient, higher global mean temperatures and an open Panama gateway. All these changes lead to a westward shift of the position of the cold tongue along the equator by up to 2000 km. This result is consistent with data from the PRISM3D Pliocene SST reconstruction. Our model further suggests that ENSO variability is present in the Pliocene climate with only slight changes as compared to today. A background climate that would resemble a "permanent" El Niño with weak to no east-west temperature difference along the equator is only found for very weak trade winds which seem unrealistic for the Pliocene climate.http://www.clim-past.net/7/903/2011/cp-7-903-2011.pdf |
| spellingShingle | A. S. von der Heydt A. Nnafie H. A. Dijkstra Cold tongue/Warm pool and ENSO dynamics in the Pliocene Climate of the Past |
| title | Cold tongue/Warm pool and ENSO dynamics in the Pliocene |
| title_full | Cold tongue/Warm pool and ENSO dynamics in the Pliocene |
| title_fullStr | Cold tongue/Warm pool and ENSO dynamics in the Pliocene |
| title_full_unstemmed | Cold tongue/Warm pool and ENSO dynamics in the Pliocene |
| title_short | Cold tongue/Warm pool and ENSO dynamics in the Pliocene |
| title_sort | cold tongue warm pool and enso dynamics in the pliocene |
| url | http://www.clim-past.net/7/903/2011/cp-7-903-2011.pdf |
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