*Koichiro Doi^1,2, Yuichi Aoyama^1,2, Kazuki Nakamura³, Tsutomu Yamanokuchi⁴, Kazuo Shibuya¹ (1.National Institute of Polar Research, 2.The Graduate University for Advanced Studies, SOKENDAI, 3.College of Engineering, Nihon University, 4.Remote Sensing Technology Center)