U.S.-France Cooperative Science Program: Simulation of Airflow over Complex Terrain Using PYREX Data

这个为期三年的奖项支持美国华盛顿大学的Dale Durran和法国图卢兹Paul Sabatier大学的evelyn Richard和Phillipe Bougeault在中尺度气象学方面的合作研究。美国和法国的调查人员已经开发出了山脉上空气流的预测模型。虽然已经认识到山地对大气环流具有重要影响，但现有的预报模式和全球气候模式在表示山地地理对大气环流的影响方面存在不足。他们合作的具体目标是增加对山脉与天气尺度空气环流之间相互作用的理解，特别强调重力波阻力。为了实现这一目标，研究人员需要更好地了解当前模型的局限性，并提高它们的灵活性。Durran博士的非流体静力模型成功地模拟了各种区域环境中的山波，但尚未用于模拟重力波与更大尺度空气流动之间的相互作用。法国研究人员为这次合作带来了他们的大尺度空气流动流体静力学模型。这两个模型都将模拟真实的和理想化的跨山流动。他们的调查将得到最近在比利牛斯地区收集的独特观测数据的帮助。这些相互补充的努力将产生能够更好地预测重力波阻力影响的模式，进而有助于山区的天气预报。

This three-year award supports U.S.-France cooperative research in mesoscale meteorology between Dale Durran of the University of Washington and Evelyne Richard and Phillipe Bougeault of the University Paul Sabatier in Toulouse, France. The U.S. and French investigators have developed predictive models for air-flow over mountains. Although it has been recognized that mountains exert a significant influence on atmospheric circulations, existing forecast models and global climate models contain deficiencies in representing the effects of mountain geography on air circulation. The specific objective of their cooperation is to increase understanding of the interaction between mountains and synoptic- scale air circulation, with particular emphasis on gravity-wave drag. In order to achieve this goal, the investigators need to better understand the limitations of the current models and improve their flexibility. Dr. Durran's nonhydrostatic model successfully simulates mountain waves in a variety of regional environments, but has not been used to simulate the interaction between gravity waves and larger scale air flow. The French investigators bring to this collaboration their hydrostatic models for larger scale air flow. Both models will be to simulate real and idealized cross mountain flows. Their investigations will be aided by unique observational data recently collected in the Pyrenees region. These complementary efforts will result in models which are better able to predict the effect of gravity-wave drag and in turn, weather forecasting in mountainous regions.