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The estimation of the advection diffusion and the optical characteristics of the Asian dust using satellite_level data

利用卫星级数据估计亚洲沙尘的平流扩散和光学特性

基本信息

批准号：
13680611
负责人：
KUSAKA Takashi
金额：
$ 0.58万
依托单位：
Kanazawa Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680611/
关键词：
Asian dust Aerosol MODIS satellite image Advection diffusion Source region of Yellow sand dust Degree of polarization Multi-spectral polarimeter Optical characteristics of Asian dust 長距離輸送シミュレーション黄砂発生源黄砂の光学特性黄砂雲黄砂光学的パラメータ偏光度

项目摘要

The Asian dust (called "Kosa" in Japan) transported from desert areas in the northern part of China often covers over East Asia in the late winter and spring.The Asian dust is also called yellow sand dust.The objectives of this study are to estimate the spatial distribution and the optical characteristics of the Asian dust using the long-range transport model and satellite_level data.The following results were obtained :(1) A method for identifying the released region and time of yellow sand dust using the long-range inverse transport model and MODIS satellite images was proposed. This method was applied to understand Kosa phenomena observed at meteorological stations in Tohoku and Hokkaido districts, Japan on March 17, 2002. As a result, it was found that dust particles were released during about 17 hours from 6h on March 15 in the neighborhood of (43N, 114E).(2) A new algorithm for estimating optical parameters (refractive index, size distribution, optical thickness) of the Asian dust and the surface reflectance simultaneously from ADEOS/POLDER data acquired at a single channel was proposed. Optical parameters of the dust cloud over a desert area and the surface reflectance were estimated inversely from the radiance and polarization data at each of 443nm and 670nm channels. As a result, it was found that the values of parameters estimated at the 443nm channel are almost the same as those at the 670nm channel except for the optical thickness.(3) Polarization measurements of the sky radiation by the multi-spectral polarimeter (PSR-1000) at the ground station in the Kanazawa city, Japan from March to April in 2000 to 2002 have been made. The wavelength dependency of degrees of polarization measured when the hazy dust was recognized in the Kanazawa City was analyzed and it was found that the wavelength dependency for polarization will be due to the size distribution of dust particles transported from the deserts in China.

冬末春初，从中国北部沙漠地区输送来的亚洲沙尘（日本称“Kosa”）经常覆盖东亚地区。亚洲沙尘又称为黄沙尘。本研究的目的是利用远程输送模型和卫星数据来估计亚洲沙尘的空间分布和光学特征。获得以下结果：（1）利用黄沙尘埃识别沙尘释放区域和时间的方法。提出了远程逆传输模型和MODIS卫星图像。该方法被应用于了解2002年3月17日在日本东北和北海道地区气象站观测到的Kosa现象。结果发现，从3月15日6点开始的约17小时内，(43N，114E)附近有沙尘颗粒释放。(2)一种估计沙尘光学参数（折射率、尺寸分布、光学厚度）的新算法。提出了从单通道获取的 ADEOS/POLDER 数据同时计算亚洲尘埃和表面反射率的方法。沙漠地区上空尘埃云的光学参数和表面反射率是根据 443 nm 和 670 nm 通道的辐射率和偏振数据逆向估计的。结果发现，除光学厚度外，443nm通道估计的参数值与670nm通道几乎相同。(3)利用日本金泽市地面站的多光谱偏振计(PSR-1000)于2000年至2002年3月至4月对天空辐射进行了偏振测量。对在金泽市识别雾霾粉尘时测得的偏振度的波长依赖性进行了分析，发现偏振的波长依赖性将归因于从中国沙漠输送的灰尘颗粒的尺寸分布。