A11E-3057:
Diurnal Variability and Kelvin Wave Propagation Through Maritime Continent
Monday, 15 December 2014
Maria K. Flatau, Naval Research Laboratory, Monterey, CA, United States, Dariusz B Baranowski, University of Warsaw, Warsaw, Poland, Piotr J Flatau, University of California San Diego, La Jolla, CA, United States and Adrian John Matthews, University of East Anglia, Centre for Ocean and Atmospheric Sciences, Norwich, NR4, United Kingdom
Abstract:
The 10 year series of the equatorial Kelvin waves obtained from the analysis of TRMM precipitation were examined to evaluate the impact of the diurnal variability of convection on the wave propagation through Maritime Continent. The convection in the Kelvin waves appears to be strongly phase locked in the area of the Maritime continent with the pronounced afternoon maximum. The diurnal phase locking is also evident as Kelvin waves propagate trough the Indian Ocean basin, suggesting that at least some Kelvin waves in this area are forced by the diurnally varying heat source related either to the convection over the land such as Eastern Africa or Madagascar, or over ocean areas with the high SST variability. We examine the hypothesis that the “matching” of the convective phase of the waves with the afternoon maximum of convection over Sumatra influences the wave strength after it crosses the Maritime Continent and can contribute to MJO propagation. The observational results based on observed Kelvin waves are supported by the results of the shallow water model of the interaction of the dry Kelvin wave with the diurnally oscillating heat source.
