GOAPP Discussion Group, November 27, 2007

Location: Gordon Riley Conference Room, Department of Oceanography, 3rd Floor LSC

Time: 3:30-5:00pm

Title: Response of the Tropical Pacific Ocean to the Madden-Julian Oscillation

Discussion Leader: Xu Zhang

Abstract:

The Madden-Julian Oscillation (MJO) is the dominant mode of variability in the tropical atmosphere on intraseasonal time scales.

Growing evidence suggests that the ocean may play an important role in defining the characteristics of the MJO. Recent work has focused on the dynamic response of the ocean to the MJO. The MJO affects the ocean through three main mechanisms: (i) increased evaporation, (ii) enhanced mixing and entrainment, and (iii) equatorial jets and waves that can generate nonlocal responses through advection and wave propagation.

Previous studies have focused mainly on the tropical Pacific Ocean where MJO-forced Kelvin waves can modulate variability in sea surface temperature (SST) and the thermocline. In turn, the modulated SST can feed back to the atmosphere. The strength of the ocean response is related to the strength of the MJO which is related to inter-annual variations such as El Nino. Numerical models are useful tools for the study of the ocean response to the MJO. Despite of significant research efforts, many issues need to be resolved in order to fully understand the coupled atmosphere-ocean dynamics related to the MJO. I will conclude by outlining some of my own research interests and possible thesis topics.