3-DIMENSIONAL RADAR ECHO STRUCTURE OF A SNOW BAND FORMED ON THE LEE SIDE OF A MOUNTAIN

被引：17

作者：

FUJIYOSHI, Y

TSUBOKI, K

SATOH, S

WAKAHAMA, G

机构：

[1] Institute of Low Temperature Science, Hokkaido Univ., Sapporo

[2] Water Research Institute, Nagoya University, Nagoya

[3] Ocean Research Institute, The University of Tokyo, Tokyo

来源：

JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN | 1992年 / 70卷 / 01期

关键词：

D O I：

10.2151/jmsj1965.70.1_11

中图分类号：

P4 [大气科学（气象学）];

学科分类号：

0706 ; 070601 ;

摘要：

A snow band, formed on the lee side of Mt. Akaiwa at Takashima Peninsula, Hokkaido, was observed by a three-dimensional scanning Doppler radar. The snow band was composed of meso-gamma-scale (approximately 20 km) radar echoes, whose interval of appearance was about 40 minutes. Inside the meso-gamma-scale echoes, were two or three convective echoes with 10 km in size. Further. each convective echo was composed of several convective cells 1-2 km in size. The snow band elongated from west to north and convective cells existing along the southern part of the snow band always appeared the most active and the highest. The convective cells successively formed only along the northern part of the snow band. The width of the snow band was dependent on the number of convective cells which composed the convective clouds. Thus, the snow band was asymmetrical in shape in the vertical plane, perpendicular to its elongated direction. On an average, the band width increased proportional to (distance) 1/3 . The band thickness linearly increased with increase in band width, arid the ratio between them increased, that is, the snow band flattened as distance increased. Averaged snow water content continued to increase over the ocean, for the convective clouds which continued to grow. But it decreased near the sea coast. This can be explained as follows: When a cloud approaches land, snow particles which are sustained in the air over the sea begin to fall near the sea coast because the averaged speed of updraft in a cloud decreases there. After landfall, the convective clouds regenerated, owing to horizontal wind convergence created by Mt. Asoiwa and weakened rapidly on its lee side.

引用

页码：11 / 24

页数：14

共 22 条

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