A Regional Climate Model for the Indian Monsoon

9502817 Vernekar这个项目的目标是调查印度季风行为的各个方面。首席研究人员将开发一个区域模式，该模式适用于检验有关季风爆发机制、季风爆发在印度次大陆向北传播、季风间歇期和季风退出的假设。为此，首席研究员已经成功地将国家气象中心(NMC)的ETA模式与全球大气环流模式联系起来，以模拟季风行为。ETA模式主要用于短期预报，并模拟了许多物理过程，包括边界层的物理、日循环、与云的辐射相互作用和对流。表面物理模块，目前是一个简单的板条能量和水桶水文模型，将被最先进的生物圈模型取代。这一生物圈模型应能更真实地反映由土壤水分和植被控制的水文循环。一旦实施，耦合模式的模拟地表通量将与观测值进行比较。然后，耦合模式将用于模拟5月初至9月底的季风。为了评估模式模拟季风时空变率的能力，将时间平均场以及产生的瞬变特征与观测结果进行比较。最后，将用耦合模式检验季风行为的各种假设。***

9502817 Vernekar The objective of this project is to investigate various aspects of the behavior of the Indian monsoon. The principal investigator will develop a regional model which is appropriate for testing hypotheses concerning mechanisms governing the onset of the monsoon, the northward propagation of the onset over the Indian subcontinent, monsoon break periods, and monsoon withdrawal. Towards this end, the principal investigator already has successfully linked the National Meteorological Center's (NMC) eta model to the global general circulation model to simulate monsoon behavior. The eta model is used primarily for short-range predictions and simulates a number of physical processes including the physics of the boundary layer, the diurnal cycle, radiation interactions with clouds, and convection. The surface physics module, currently a simple slab energy and bucket hydrology model, will be replaced with a state-of-the-art biosphere model. This biosphere model should provide more realistic representations of the hydrologic cycle as governed by soil moisture and vegetation. Once implemented, the coupled model's simulated surface fluxes will be compared with observations. The coupled model will then be used to simulate the monsoon from the beginning of May to the end of September. To assess the ability of the model to simulate the space-time variability of the monsoon, the time- averaged fields as well as the transient characteristics produced will be compared with those from observation. Finally, the various hypotheses of monsoon behavior will be tested with the coupled model. ***