Examination of 3-6 day Disturbances over Equatorial Indonesia Based on Boundary Layer Radar Observations during 1996-1999 at Bukittinggi, Serpong and Biak

抄録

Spectral features of lower tropospheric horizontal wind observed during 1996-1999 by Bukittinggi, Serpong and Biak boundary layer radars show 3-6 day periodicities in zonal and meridional components and longer period zonal wind oscillations. Using bandpass filtering analysis the 3-6 day modes show a westward phase speed of about 700 km day^-1 and a zonal wavelength of about 3500 km, and propagate through the Indonesian maritime continent when the westerly wind is prevailing at Biak.