Factors Controlling the Structure and Distribution of Precipitation in Hurricanes

根据美国天气研究计划，首席调查人员将调查飓风中降水的物理控制。这项研究的主要目的是通过使用嵌套网格的高分辨率大气中尺度模式进行数值模拟，检查控制与热带气旋有关的积云对流和降水的结构和分布的物理过程。飓风预测模型必须准确地模拟这些特征，以便改进强度和跟踪预报以及登陆时的降雨预报。这项研究将解决以下具体的科学问题：决定飓风内降水分布和降雨率的基本物理过程是什么？模拟的湿对流过程对模式分辨率、物理参数化和模式初始化的敏感性是什么？降水和对流加热分布中的风暴尺度变化与飓风结构的各个方面、风暴与环境的相互作用以及最终的飓风路径和强度预报有何关系？该项目将产生飓风Bonnie和Georges的三维降水结构和分布的综合数据集。它还将采用高分辨率嵌套网格建模系统(PSU/NCAR MM5，具有专门为飓风模拟开发的初始化)，可用于解决与飓风研究和业务预报有关的问题。

Under the U.S. Weather Research Program, the Principal Investigators will investigate the physical controls of precipitation in hurricanes. The main objective of this research is, through numerical simulations using a nested-grid, high-resolution atmospheric mesoscale model, to examine the physical processes governing the structure and distribution of cumulus convection and precipitation associated with tropical cyclones. Hurricane prediction models must accurately simulate these features in order to improve intensity and track forecasts as well as the rainfall forecast at landfall. The research will address the following specific scientific questions:What are the fundamental physical processes that determine the precipitation distribution and rain rate within a hurricane?What are the sensitivities of simulated moist convective processes to model resolution, physical parameterization, and model initialization?How are storm-scale variabilities in the precipitation and convective heating distributions related to various aspects of hurricane structure, storm-environmental interactions and, ultimately, hurricane track and intensity forecasts?The project will produce comprehensive data sets of the three-dimensional precipitation structure and distribution of Hurricanes Bonnie and Georges. It will also adapt a high-resolution nested-grid modeling system (the PSU/NCAR MM5 with an initialization specifically developed for hurricane simulations) that can be used to address issues related to both hurricane research and operational forecasting.