HR: 0800h
AN: A11B-0381    [Abstracts]
TI: Balloon borne measurements of aerosol and cloud particles over Japan during PACDEX
AU: * Sakai, T
EM: tetsu@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Orikasa, N
EM: norikasa@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Nagai, T
EM: tnagai@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Murakami, M
EM: mamuraka@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Tajiri, T
EM: ttajiri@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Saito, A
EM: asaito@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AU: Yamashita, K
EM: kayamash@mri-jma.go.jp
AF: Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052, Japan
AB: This paper presents the preliminary result of the balloon borne measurements of the aerosol and cloud microphysical properties over Tsukuba (36.1°N, 140.1°E), Japan, on 10 and 22 May 2007. The purpose of the measurement is to study the influence of Asian mineral dust on ice clouds formation in the middle and upper troposphere. The balloon measured the vertical distributions of aerosol number size distribution (0.13 to 3.9 μm in threshold radius, 8 sizes) by use of the optical particle counter, cloud size (10 μ m to 5 mm in the longest dimension), shape, and number concentration by use of the hydrometer videosonde, humidity by use of SnowWhite hygrometer, and temperature and pressure by use of Meisei RS-01G radiosonde between altitudes of 0 and 16 km. The aerosol size distribution showed bimodal distribution with mode radii of <0.13 μm (fine mode) and about 0.8 μm (coarse mode) over the troposphere (0-13.5 km in altitude). The number concentrations ranged from 150 to 1 cm^-3 in the fine mode and from 3 to 0.1 cm^-3 in the coarse mode. High depolarization ratio (>10%) obtained from the ground-based Raman lidar measurement revealed the presence of nonspherical dust in the coarse mode. Columnar, bullet-like, and irregular ice crystals with 10-400 μm in size were detected between altitudes of 8 and 13 km on 10 May and 10 and 13 km on 22 May. The maximum crystal concentration was 0.15 cm^-3. We discuss the possibility of the formation of the ice cloud from the dust based on the result of the measurements.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting