Open AccessWave Activity on the Tropical Easterly Jet
Author(s) -
Sharon E. Nicholson,
Albert Barcilon,
Malakondayya Challa,
Jeramy Baum
Publication year - 2007
Publication title -
journal of the atmospheric sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.853
H-Index - 173
eISSN - 1520-0469
pISSN - 0022-4928
DOI - 10.1175/jas3946.1
Subject(s) - african easterly jet , tropical wave , climatology , jet (fluid) , monsoon , atmospheric sciences , vorticity , geology , meteorology , environmental science , geography , tropical cyclone , physics , vortex , thermodynamics
This article examines the question of the existence of waves on the tropical easterly jet (TEJ) over West Africa. The TEJ is a well-known feature of the Asian monsoon and waves on the jet have been implicated in various weather phenomena. Its role in West African meteorology has received little attention. A model simulation of wet and dry years over West Africa predicted wave development on the TEJ. NCEP reanalysis data confirmed the existence of these waves, using case studies in the dry year 1983 and the wet year 1950. Both the simulated and observed waves are of planetary scale, with a period of 5–6 days. Potential vorticity (PV) theory suggests that they develop via interactions between the surface and the TEJ. Overall, the results suggest that interactions between the TEJ and African easterly jet play an important role in the development of wave disturbances over West Africa.