Kelvin wave propagation along the southern coasts of Sumatra, Java, and Lesser Sunda Islands generated by Madden-Julian Oscillation (MJO) Phase 3

Abstract

Kelvin wave propagation along the southern coasts of Sumatra, Java, and Lesser Sunda Islands generated by the Madden-Julian Oscillation (MJO) phase 3 (April 28 – May 6, 2004) has been studied by using sea surface height anomaly (SSHA) data simulated by a 1/8° global version of the HYbrid Coordinate Ocean Model (HYCOM), satellite-observed outgoing longwave radiation (OLR) data, and zonal wind data. In order to investigate the influences of MJO known as the intraseasonal oscillation (30–90 days), analysis of the data was carried out after 10–100 days band-pass filtering. The analysis results show that the intraseasonal oscillation SSHA along the coasts of Sumatra, Java, and Lesser Sunda Islands generally have a spectral peak at 91 days associated with the spectral peak of the MJO, except for Sunda Strait (61 days), southern coast of West Java (55 days), Sawu Sea (58 days), and Ombai Strait (100 days). Further analysis suggests that the MJO phase 3 generates Kelvin waves propagating eastward along the coasts of Sumatra, Java, and Lesser Sunda Islands with phase speed ranging from 2.56 to 3.85 m/s.