Studies of Ice in Clouds

降水的形成具有重要的科学意义和现实意义。众所周知，大气中的冰在降水的发展中起着至关重要的作用，但云中冰形成的所有机制并没有得到很好的理解。云物理学家面临的最基本的问题之一是解释云中冰粒子数量的增加，这超出了大气中可用的冰核粒子数量的预期。在先前资助的NSF研究中，主要研究人员参与了云中冰形成的研究。主要的发现包括，在某些类型的云中，冰的形成发生在云顶附近，并且似乎在云顶附近加强。这些观测表明，与目前公认的过程相比，冰增强的机制有着根本的不同。这项拟议的研究将继续对云中的冰进行实地研究。主要目标是确定冰粒子的起源和形成机制，特别强调云顶的冰。这些目标将通过获取积云和高积云的数据集来实现。数据集将包括来自新的机载仪器的信息，这些仪器将提高探测冰的能力，确定云内冰的细尺度结构，并测量湿度。

The formation of precipitation is of great scientific as well as practical significance. It is known that atmospheric ice plays a crucial role in the development of precipitation, but not all the mechanisms by which ice forms in clouds are well understood. One of the most fundamental problems facing cloud physicists is explaining the enhancement of the number of ice particles in clouds beyond what would be expected from the number of ice nucleating particles that are available in the atmosphere. Under previously sponsored NSF research, the Principal Investigators have been involved in research on ice formation in clouds. Major findings include that, in certain types of clouds, ice formation occurs and appears to be enhanced near cloud top. These observations imply a fundamentally different mechanism for ice enhancement than the currently accepted process. This proposed research will continue field studies of ice in clouds. Primary goals are to determine the origins and mechanisms of formation of ice particles with particular emphasis on ice at cloud tops. These goals will be pursued through the acquisition of data sets in cumulus and altocumulus clouds. The data sets will include information from new airborne instruments which will provided improved capabilities in detecting ice, determining fine scale structure of streamers of ice within clouds and in measuring humidity.