[M-SD35] Future Missions of Satellite Earth Observation

[MSD35-P10] High-frequency observations of water vapor, isotope, ice clouds and radiation budget by FTS small satellite constellation

*Nawo Eguchi¹, YASUKO KASAI², Kei Yoshimura³, Ryoichi Imasu⁴, Kozo OKAMOTO⁵, Naoko Saitoh⁶, Toshiya Hanada⁷ (1.Research Institute for Applied Mechanics, Kyushu University, 2.National Institute of Information and Communications Technology, 3.Institute of Industrial Science, University of Tokyo, 4.Atmosphere and Ocean Research Institute, University of Tokyo, 5.Meteorological Research Institute, 6.Center for Environmental Remote Sensing, Chiba University, 7.Faculty of Engineering, Kyushu University)

Keywords:Fourier Transform Spectrometer, small satellite, water vapor, water vapor isotope, far infrared

Global observations of water vapor and clouds in the Earth's atmosphere not only provide a more quantitative understanding of the radiation balance and the maintenance and variability of the climate through it, but also the information of upper tropospheric water vapor and ice clouds improve the accuracy of typhoon forecasting. Furthermore, it has been reported that the accuracy of numerical weather prediction is improved by using atmospheric motion vectors (AMV) derived from high-frequency water vapor distribution and the water vapor isotopes as input values.
The purpose of this mission is not only a quantitative understanding of the Earth's radiation balance, but also to improve the forecast accuracy of a meteorological disaster through an understanding of the precipitation process and atmospheric disturbances by the high frequency observation of the water vapor, its isotopes and ice clouds in the troposphere and stratosphere.
In the observation, multiple small Fourier-Transform Spectrometer (FTS) instrument (100 kg class) (30- 40 satellites) will be used to observe the East Asian region including Japan at intervals of about one hour. The observation wavelength range is in the far infrared region (100 to 670 cm-1; 15 to 100 μm), and a resolution of 0.1 cm-1 is assumed. The satellite is expected to have an orbital inclination of 38 degrees, an altitude of 200 to 300 km, a vertical resolution of 3 km, and a Swath of 40 km at nadir viewing.
In this presentation, using the Walker Delta pattern constellation method, we present the results of numerical simulations of satellite orbits that observe the Japanese region within 30 minutes using 48 satellites, and discuss the science that can be obtained from them.