The proposed experiment is a collaborative two-year study of the air-sea fluxes, air-sea interaction, convection and the upper ocean response to the variations of the summer monsoon as it oscillates between active and the lulls in between (break periods). A pilot study, the joint air-sea monsoon interaction experiment (JASMINE) will conduct an oceanographic and meteorological survey of the Bay of Bengal region. Air-sea fluxes, the state of the atmosphere and convection within the atmosphere will be determined in a region that has been observed to be a centroid of intraseasonal variability in the summer monsoon. JASMINE is a collaborative project of the University of Washington, University of Hawaii, and the University of Colorado.
This component of the collaboration will examine the surface energy balance and the upper ocean heat balance, the hydrological cycle and the freshwater budget of the upper ocean, and the ocean barrier layer.
The warm pool of the Indian Ocean appears different from the tropical western Pacific Ocean in that meridional heat transports are an important part of the heat balance. Scientific questions regarding the nature of heat partitioning, net heat flux into the Indian Ocean and its annual cycle, and heat balance and surface energy budget variation over intraseasonal cycles, will be addressed. The Bay of Bengal sector differs form the Pacific Ocean in that there is a large input of freshwater from river sources as well as precipitation. Scientific questions regarding the annual cycle and geographic distribution of this freshwater input, role of freshwater input in modifying the mixed-layer and barrier layer structure and the predictability of SST, and freshwater balance and how it varies on intraseasonal through interannual cycles, will be addressed. The barrier layer (the higher saline layer between the surface layer and the thermocline) plays a critical role in determining the nature of the western Pacific Ocean. Scientific questions regarding the possible existence and role of a barrier layer in the Indian Ocean will be addressed.
The study is important since gathering and subsequent analysis of a comprehensive set of data, will yield insights into the air-sea interactions during break and active periods of the monsoon. The accurate prediction of monsoon onset and monsoon rainfall is a scientific challenge that also has enormous economic consequences.
