Abstracts for the 5th International GAME Conf.

3-5 October 2001

Aichi Trade Center

Nagoya Japan

DIURNAL VARIATIONS OF WIND AND CONVECTIVE ACTIVITY IN INDONESIA

R. Araki (1), M.D. Yamanaka (1), S. Ogino (1), F. Murata (1), N. Okamoto (1), H. Hashiguchi (6)

The diurnal variations were analyzed based on data obtained with a boundary layer radar (BLR) at Serpong near Jakarta, West Java, Indonesia (6.4S, 106.7E, 50MSL) in November-February (rainy season) from 1994 to 1999, and in July-August (dry season) from 1995 to 2000. Meridional winds were weak in average every month, but features like a land-sea breeze circulation was observed every clear day in dry season. Northerly (sea breeze) was observed at a height range of 0.5-1.2km, and southerly (land breeze) was at 1.2-2.0 km from about 1200 LT to evening. They are reasonable because Serpong is situated south of the Java Sea coastline (roughly east-west). In the rainy season, the land-sea breeze circulation was not clearer than in the dry season. For zonal winds, the background flow was easterly in the dry season, and was westerly in the rainy season. In the dry season, the mixing layer developed during 08-18 LT. And the deviation from mean diurnal variations of zonal winds was westerly inside the mixing layer. In the rainy season, the mixing layer was observed during 08-18 LT. But its development was weak. And easterly dominated during 06-18 LT. The interannual variations of the diurnal variations were not clear in the dry season. Particularly the interanuual variations of the land-sea breeze circulation in the rainy season were more fluctuating than in the dry season. In the dry season, it is suggested that the diurnal variations of the zonal winds have some relationships to the development of the mixing layer. The causes of the diurnal variations of zonal winds in the rainy season are different from those in the dry season. The developments of the land-sea breeze circulation and the mixing layer were weak in the rainy season, probably because the solar irradiance at the ground surface in the raniy season is less than in the dry season. Interannual variations of rainfall amounts and convective clouds must be compared with those of the diurnal variations of the winds.

Submittal Information

Name : Date :
    Ryuzo Araki
    31-May-01-22:04:32
Organization : Theme :
    Graduate School of Science and Technology, Kobe University
    Theme 1
Address : Presentation :
    Nada-ku, Kobe, Hyogo 657-8501
    Poster or oral
Country : Abstract ID :
    Japan
    T1RA31May01220432
Phone : Fax :
    +81 78 803 5791
    +81 78 803 5757
E-mail :
    araki@shizen.sci.kobe-u.ac.jp