Microphysical Aspects of Cumulus Clouds

积云的微观物理方面

• 批准号: 8715458
• 负责人: James Telford
• 金额: $ 55.99万
• 依托单位: Nevada System of Higher Education, Desert Research Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-12-15 至 1991-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8715458&HistoricalAwards=false
• 关键词: Microphysical; Aspects; Cumulus; Clouds

Within the visual identification of clouds, active mixing takes place between the cloudy air and the drier air of its environment. Recent observations of stratocumulus entrainment provide evidence that dry air mostly enters from the cloud top instead of from the lateral boundaries. At present, the entrainment mechanism is not fully understood. The entrained volume, with the cooler and drier air from above, dilutes the cloudy air, is negatively buoyant, and therefore descends within the cloud. Based on field observations and laboratory experiments, the entrained blob of air is envisioned to behave like a spherical vortex, with strong updraft in the middle of the blob and slower rising or descending air around the periphery. Under this grant, Profesor Telford will examine the dynamics of a turbulent spherical vortex and implement it in a cloud model. Since the entrainment processes may play a significant role in explaining the finite life time of cumulus clouds and in predicting various cloud drop size spectra observed around the world, Professor Telford's new theory, if successfully tested, will be a major contribution to cloud modelling.

在云的视觉识别中， 位于多云的空气和其环境中干燥的空气之间。 最近对层积云卷吸的观测提供了证据 干燥的空气主要从云顶进入， 横向边界。 目前，夹带机制不是 完全理解 夹带的体积，与冷却器和干燥的空气从上面， 稀释了浑浊的空气，具有负浮力，因此下降 在云中。 根据实地观察和实验室 实验中，夹带的空气团被设想表现得像一个 球形漩涡，在水滴中间有强烈的上升气流， 外围缓慢上升或下降的空气。 根据本 格兰特，格兰特或特尔福德将研究一个动荡的动力学 球形涡并在云模型中实现。 以来 夹带过程可能在解释 积云的有限寿命和预报各种云 在世界各地观察到的液滴大小光谱，特尔福德教授的新 理论，如果成功测试，将是对云计算的重大贡献。 建模