本帖最后由 q5968661 于 2009-1-21 20:44 编辑
Lenticular clouds are lens-shaped clouds that can result from strong wind flow over rugged terrain. At the time of this photo, the winds were blowing around 30-40 mph from right to left, forming several lenticular clouds. Sometimes they stack up like pancakes in multiple layers as are several depicted in this first photo. The strong flow produces a distinct up and down wavelike pattern on the lee side of the mountain or large hill and the lenticular clouds tend to form at the peaks of these waves. They sometimes are very round and the edges are so well defined that they resemble flying saucers. This close up sequence shows a large lenticular cloud at various stages of illumination as the sun moved lower on the horizon and lit the cloud from below. Another lenticular cloud can be seen in the background of the last frame of the sequence. These photos were taken on January 25, 1999 in Plymouth, NH, by James D. Rufo, a Plymouth State meteorology graduate. Mrs. Lorraine Brown of Bristol NH captured this same cloud formation from about 20-25 miles further away in these pictures. Lenticular clouds are often placed into the middle cloud category since they are most common at those altitudes. Plymouth State meteorology graduate, Jay Shafer, has also provided some stunning additional lenticular pictures taken around the White Mountain region of New Hampshire.
原文
Explanation: What's happening above those mountains? Several clouds are stacked up into one striking lenticular cloud. Normally, air moves much more horizontally than it does vertically. Sometimes, however, such as when wind comes off of a mountain or a hill, relatively strong vertical oscillations take place as the air stabilizes. The dry air at the top of an oscillation may be quite stratified in moisture content, and hence forms clouds at each layer where the air saturates with moisture. The result can be a lenticular cloud with a strongly layered appearance. The above picture was taken in 2002 looking southwest over the Tarurua Range mountains from North Island, New Zealand.
成大
说明:这些山有什么特别的吗？ 进而导致成群的云系堆积成特殊的荚状云 。 一般来说，气流的水平运动远大于垂直运动，然而有时候，像是气流通过山脉或是丘陵 ，受到地形的抬升作用而垂直振荡，直到达到平衡为止。 这团振荡气团周遭的干空气，湿度分布层层不同 ，因此当空气受到扰动而达饱和时，进而产生这种具有明显层状结构的荚状云 。上面这张影像是2002年在纽西兰 北岛 ， 往西南方的塔拉鲁阿山脉上空所拍摄。 |
置顶卡
变色卡
千斤顶
显身卡
