ANNUAL VARIATIONS OF CLOUD LIQUID WATER IN THE POLAR REGION USING SATELLITE DATA

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Seasonal and annual variations of column liquid water and precipitable water have been investigated using the SSM/I data of DMSP satellite. Meteorological radar and microwave radiometer observations were carried out at Syowa Station in 1988 and 1989. The Antarctic satellite data of 1988-1990 have been analyzed mainly, although the data of 1987-1995 have been dealt with. The Arctic data of 1992-1995 have been analyzed. The variation of 22 GHz and 37 GHz brightness temperature are roughly same as the variation of precipitable water and column liquid water in the atmosphere, respectively over open sea area. Some results of the brightness temperatures are described on behalf of those of column liquid water and precipitable water.High brightness temperature areas of 22 and 37 GHz were admitted near the off coast of Syowa Station according to the SSM/I image, when precipitation associated with low pressure was observed at Syowa Station. It was found that column liquid water was high in the e … More ast of the cloud band but was low in the west of cloud band. This result was similar to the characteristic of band cloud structure observed by meteorological radar at Syowa Station. The variation of precipitable water showed a peak aroung February, but the variation of column liquid water had two peaks in a year which were around February to April and around October to December. Total precipitation of 1989 was twice larger than that of 1988. Comparing the SSM/I images of 1988 and 1989 along the coast, the frequency of the days of high column liquid water was bigger in 1989 than in 1988. Especially, the big difference of both years was found around March to May and around October to November.It was found in the Arctic data that there were 2 periods with different values of precipitable water in a year. One was the period from May to October and others were from January to April and from November to December. The variation of 1993 data showed some difference from the data of other years. It might be related to the area of sea ice extension in three years in the Arctic. Maximum colum liquid water was 0.2 kg/m2 derived from SSM/I in the Arctic in 1992-1995, except 1993. Less