Satellite and Radiation Studies of the Southwest-East Asian Monsoon

本研究探讨了西南-东亚季风中云系统、地表和辐射之间的相互作用。它代表了在美国国家科学基金会的赞助下，将卫星辐射和辐射收支测量应用于季风科学中涉及季风行为的年际和季节内方面以及热源和汇的当前问题的持续努力。拟议研究的首要科学目标有两个：A)利用INSAT地球同步卫星测量来确定亚洲季风中深层有组织对流和热带风暴的发展和运动如何调节与低频相关的云量异常的幅度和相位传播特征动力学 振荡。研究热带风暴中主要热源区域的运动和波动如何控制印度洋-西太平洋偶极子的尺度、方向和幅度，该偶极子指示低频振荡的主要源区域。发展中光谱分辨率辐射传输模型，将INSAT的测量结果结合起来，为参数化云计算规定云量。诊断了垂直辐射通量发散曲线波动的调制。结合这些剖面分解低频振荡的垂直结构。B)借助INSAT和AVHRR卫星测量以及TIPMEX-86地面测量，显示了整个青藏高原地区在夏季风过渡期间和整个夏季风过程中，地表边界条件的变化如何导致辐射通量散度剖面的大日强迫梯度。研究穿越喜马拉雅屏障向北渗透的低频率季风事件如何减少地面强迫的作用，代之以云强迫辐射剖面结构。这项研究很重要，因为它有可能提供有关亚洲季风系统（地球上最活跃的区域环流）与其他全球天气和气候系统（包括影响美国的天气和气候系统）之间关系的新知识。

This research addresses the interaction between cloud systems, land surfaces and radiation within the Southwest-East Asian Monsoon. It represents an ongoing effort under NSF sponsorship to apply satellite radiance and radiation budget measurements to current problems in monsoon science involving both interannual and intraseasonal aspects of monsoon behavior and heat sources and sinks. The foremost scientific objectives of the proposed research are twofold: A) Utilize INSAT geosynchronous satellite measurements to determine how the development and movement of deep organized convection and tropical storms within the Asian monsoon regulate the amplitude and phase propagation characteristics of cloudiness anomalies associated with low frequency intraseasonal oscillations. Investigate how the movement and fluctuations of the predominant heat source regions within tropical storms controls the dimensions, orientation, and amplitude of the Indian Ocean-Western Pacific dipole designating the major source region of low frequency oscillations. Develop medium spectral resolution radiative transfer models, which incorporate INSAT measurements to prescribe cloudiness for parameterized cloud calculations. Diagnose the modulation of the vertical radiative flux divergence profiles fluctuations. Decompose the vertical structure of the low frequency oscillations in conjunction with these profiles. B) With the aid of INSAT and AVHRR satellite measurements, and the TIPMEX-86 surface measurements, show how variations in surface boundary conditions throughout the region of the Tibet Plateau, during the transition into and throughout the course of the summer monsoon, lead to large diurnally forced gradients in the radiative flux divergence profiles. Investigate how the northward penetration of the low frequency monsoon episodes across the Himalayan barrier diminish the role of surface forcing, replacing it with a cloud forced radiation profile structure. This research is important because it has the potential of providing new knowledge of how the Asian monsoon system, the most energetic regional circulation on earth, is related to other global weather and climate systems, including those affecting the United States.