Air-Sea Interaction Observed from Aircraft Measurements in DYNAMO

The NOAA WP-3D research aircraft made 12 flights over the equatorial Indian Ocean as part of the Dynamic of the Madden-Julian Oscillation (DYNAMO) field campaign. The comprehensive measurements included flight-level state and thermodynamics variables, turbulence and high-rate temperature and water vapor perturbations, cloud microphysics, atmospheric radiation, surface imaging and waves, and convective precipitation activities from the vertical-scanning Doppler radar and the lower fuselage horizontally scanning radar. Measurements based on the aircraft also include air expendables such as GPS windfinding dropsondes, Airborne eXpendable Bathy Thermographs (AXBT) and Airborne eXpendable Conductivity Temperature and Depth probes (AXCTD) for co-located and simultaneous atmospheric and oceanic profiling. This presentation will present results on air-sea interaction in different stages of MJO development. We will first discus the air-sea temperature variability and the associated boundary layer structure seen from aircraft flight level measurements as well as dropsonde measurements in various phase of the MJO. Secondly, we will discuss the interaction between mesoscale convection and the atmospheric boundary layer. The thermodynamic and wind structure of the cold pool boundary layers will be illustrated using spatially coherent arrays of dropsonde measurements in conjunction with flight level measurements.