Characteristics of a Cloud Band off the West Coast of Hokkaido Island as Determined from AVHRR/NOAA, SSM/I and Radar Data

Abstract

Using a combination of data from various remote sensing devices, the investigation reveals the characteristics of one case of a Cloud Band. Data from AVHRR/NOAA and VISSR/GMS are used for the cloud top structure, while data from SSM/I 85GHz channels and Keifu-maru radar are used for the internal signature of the Cloud Band. The analyses of two scenes reveal the asymmetric structure of the Cloud Band in the east-west direction: the western part includes a large amount of cloud water and the precipitation area is in the central part. The eastern part comprises less cloud water and precipitation. These suggest that the updraft region is located in the western part of the Cloud Band. While these internal signatures in the east-west direction are common to both scenes, the appearance of the cloud top structure differs between the two. In addition, the internal signatures differ quantitatively in the north-south direction. The variation in the structure seems to reflect the effect of a meso-α cyclone. This implies that the Cloud Band is a front-like feature in a meso-α cyclone, which develops from a simple discontinuous line between a northwesterly monsoon and a northeasterly wind in the lower troposphere.