J. Climate, sub judice Correspondence address:
The sensitivity of the atmospheric circulation to sea surface temperature (SST) anomalies in the tropical and subtropical South Atlantic Ocean is studied by means of simulations with an atmospheric general circulation model (GCM). Two types of prescribed SST anomalies are used, motivated by previous...
Main Authors: | , , , , |
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Other Authors: | |
Format: | Text |
Language: | English |
Published: |
2003
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Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.380.5213 http://iri.columbia.edu/~awr/papers/RFM_JCL03_REV.pdf |
Summary: | The sensitivity of the atmospheric circulation to sea surface temperature (SST) anomalies in the tropical and subtropical South Atlantic Ocean is studied by means of simulations with an atmospheric general circulation model (GCM). Two types of prescribed SST anomalies are used, motivated by previous analyses of data. The first occurs during austral summers in association with a strengthening of the South Atlantic Convergence Zone (SACZ), and consists of cold SST anomalies over the subtropical South Atlantic. The second is the leading seasonally varying empirical orthogonal function of SST, consisting of warm basin-scale anomalies with maximum amplitude in the subtropics during January–March and at the equator in June. An ensemble of about 10 seasonal simulations is made using each type of anomaly, focusing on the January–March period in the first case, and the January–June seasonal evolution in the second. During January–March both experiments yield a statistically significant baroclinic response over the subtropical Atlantic with dipolar SACZ-like anomalies. Some evidence of positive feedback is found. The response is shown to be fairly similar in pattern as well |
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