Author(s): Fanny Kristianti; Tomohito Yamada
Linked Author(s):
Keywords: Hydrologic cycle; Radiosonde; Land; Atmosphere boundary layer; Turbulence
Abstract: The GEWEX Asian Monsoon Experiment (GAME) was started in 1996, as part of GEWEX (Global Energy and Water Cycle Experiment) under WCRP (World Climate Research Program). The project purpose is to understand the role of the Asian Monsoon as major component of the global energy and water cycle. Human life and environment can be affected seriously by droughts or floods, associated with monsoon rainfall variability, which brings into the motive of GAME project. Under the project, radiosonde observation was implemented on summer season in Sukothai, Thailand. Vertical profile of atmosphere which affected strongly by land atmosphere situation and diurnal cycle can be observed from radiosonde data. The interaction between land’s surface and atmosphere is an important key to understand the hydrological cycle. The interaction occurs in the lowest region of the atmosphere called Atmospheric Boundary Layer (ABL) which works as channeling layer for fluxes from land to atmosphere. One of the important process helping the fluxes transfer in ABL is turbulence, which strength is related to the heating or cooling from the ground and directly from the solar activity. The more intense turbulence, for example during the daytime due to solar heating, will create thicker ABL situation. Based on GAME Thailand observation data, ABL height shows thick layer of atmospheric boundary approximately 3 km, resulted from intense turbulence causing instability situation which create good environment for strong convection cycle to occur. After investigating the ABL by Large Eddy Simulation, it is found that the diurnal cycle in the Thailand area is strong and therefore causing high fluctuation on turbulent intensity in ABL.
Year: 2018