A study of thermals in cumulus clouds
A study of thermals in cumulus clouds
复制标题
积云中的热气流研究
DOI：
10.1256/qj.03.180
复制
发表时间：
2005
影响因子：
8.9
通讯作者：
W. Cooper
中科院分区：
文献类型：
--
作者：
A. Blyth;S. Lasher;W. Cooper
据观察，佛罗里达浅层积云内的热气流中的空气运动与实验室热气流中观察到的环流相似。在大多数层面上，个别热气流的上升气流存在向外流动，并且通常在上升气流或云的边缘观察到下降气流。向云中心广泛的向内流动，偶尔观察到狭窄但强烈的上升气流，让人想起在实验室热气流后部发现的尾巴。在几个热气流的中心经常观察到液态水含量减少的区域，其中上升气流和水平一维散度最强，并且两次观察到完整的孔洞。虽然水平风切变总体较弱，但在少数情况下很显着，导致云中的流型不对称。
Air motions in the thermals contained within shallow Florida cumulus clouds were observed to be similar to the circulation observed in laboratory thermals. There was outward flow in the updraughts of individual thermals at most levels and there were usually downdraughts observed at the edges of the updraught or of the cloud. Widespread inward flow towards the centre of the cloud and a narrow, but strong, updraught was occasionally observed, reminiscent of the tail found at the rear of the laboratory thermals. A region of reduced liquid water content was frequently observed in the centre of several thermals where the updraught and horizontal 1D divergence were strongest, and complete holes were observed on two occasions. Although horizontal wind shear was generally weak, it was significant in a few cases, causing the flow pattern in the cloud to be asymmetric.