DEPARTMENT OF MARINE SCIENCES
UNIVERSITY OF CONNECTICUT
AN INVESTIGATION OF LATENT, SENSIBLE AND NET HEAT EXCHANGE IN THE DYNAMO PROGRAM
The ONR LASP DRI was conducted in the Indian Ocean with the DYNAMO program to study the Madden-Julian Oscillation (MJO). The MJO is a quasi-periodic disturbance with a period between 30-90 days that propagates eastward from the Indian Ocean to the Central Pacific at an average speed of 5 m/s. The MJO is characterized by an active phase with strong winds, deep convection and precipitation and a suppressed phase with strong solar insolation, light winds and ocean heating. Realistic simulation of the MJO remains a long-standing challenge for weather forecast and general circulation models. Therefore, improvements to our ability to forecast the MJO are expected to improve our ability to forecast weather in the tropics.
An objective of the LASP/DYNAMO is to improve our understanding of surface heat exchange in the tropics and its role in MJO formation and propagation. Toward this objective, direct covariance flux packages were deployed on the R/V Revelle to directly measure the latent and sensible heat fluxes. The talk will describe how these measurements are being used to improve surface heat flux parameterizations. The improved heat flux estimates are combined with the radiative fluxes to compute the net heat and surface energy flux into the ocean. The talk will discuss the initialization and strength of MJO convection in the Indian Ocean as related to the oceanic storage of energy during the suppressed phase and release of this energy during the active phase, i.e., the ocean as the MJO capacitor.