Abstract

Folland et al.1 have reported that persistently dry and wet periods of several years in the Sahel have been accompanied by global-scale patterns of sea-surface temperature (SST) anomaly. They also demonstrated that the response of a general circulation model (GCM) of the atmosphere to an observed composite SST difference field between a number of such dry and wet periods showed substantial reduction in Sahel rainfall compared with values from a simulation with climatological SSTs. I examine here the same model's response to the individual components of the composite SST difference field in the Atlantic, Pacific and Indian Oceans. It is found that over the western Sahel, the Atlantic and Pacific fields have a comparable effect in reducing rainfall whereas the Indian Ocean field produces a slight enhancement. Results suggest that, over the eastern Sahel, the Indian Ocean has the dominant role in reducing rainfall.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.