Satellite image sensors are widely used in the field of meteorology, land-use classification, resource search and marine monitoring. On another side, "sounders", which derive spatial profile of meteorological parameters and atmospheric species from multichannel data, show the steady progress. In this report the satellite sensors for the middle atmosphere (stratosphere and mesosphere) measurement are surveyed with some examples of the measurement.
The measurement of global atmospheric environment from hemisphere to mesosphere by lidar are presented. The examples of the measurement on aerosol distribution in troposphere and stratosphere, cloud, air density at more than 30km height, O3 in troposphere and stratosphehre, Na layer at 90 km height, Ca and Ca+ layers at 90 km and 100km, respectively, H2O distribution in troposphere, and wind velocity in troposphere are introduced. OH radicals in stratosphere and temperature in troposphere are also pointed out as new targets of lidar measurements.
Recent researches on desert aerosols which have been increasing due to desertification were reviewed. The main topics here were; (1) long-range transport of desert aerosols, and (2) radiation balance changes caused by the existence of desert aerosols. Results of some important studies were described and problems to be solved were pointed out. The Saharan dust and the Asian dust (or yellow sand) were described as exsamples of long-range transport. Optical properties of the Saharan dust were discussed as well as the vertical profiles of heating and cooling rates of the atmosphere. Comprehensive and quantitative understanding of the desert aerosols is essential, which requires threedimensional and continuous observations and theoretical as well as experimental studies on the optical properties of desert aerosols.
The results of lidar measurements of the stratospheric aerosol increases after the El Chichón eruption are reviewed. The eruption of El Chichón loaded about 10 Tg sulfuric acid aerosols in the stratosphere. The aerosols rounded the earth in about three weeks and dispersed towards the poles gradually. It is conjectured on the basis of depolarization meaeurements that a lare amount of volcanic ash was also injected into the stratosphere. The stratospheric aerosols scatter the solar radiation and cool the ground, while they absorb the radiation, heating the stratsphere. Some model calculations are also reviewed to evaluate the effects of the stratospheric aerosols loaded by the El Chichbn eruption on the temperature.
Marine Observation Satellite-1 (MOS-1) will be launched by a N-II launch vehicle from Tanegashima Space Center, NASDA in the January-February period of 1987. Main mission objectives of MOS-1 are to observe ocean, land and atmosphere using three radiometers (MESSR, VTIR, MSR) covering visible, nearinfrared, thermal infrared and microwave wavelength region, and to establish fundamental technologies of earth observation satellite total system. In order to accomplish these objectives, NASDA is developing MOS-1 space segment and ground segment and planned MOS-1 Verification Program (MVP) to evaluate the total MOS-1 system by using MOS-1 data obtained after launch of MOS-1. In order to develop MOS-1 data distortion correction method and earth observation system evaluation method and to prepare for the MVP, NASDA conducted airborne observation experiments using three radiometers mounted on an aircraft turbo-prop type "Merlin IV A' equivalent to MOS-1 MESSR, VTIR and MSR in cooperation with cooperative agencies from November, 1984 through September, 1985. NASDA obtained airborne MESSR, VTIR, MSR data and aerial photograph data in winter and summer during 11 days over several test sites in Kanto of Honsyu and in Hokkaido. Cooperative agencies obtained ground/sea truth data. By using airborne data and ground/sea truth data, distortion correction algorithms and observation system evaluation algorithms have been developed. These algorithms have been installed in MOS-1 data processing facility. Based upon the airborne observation experiments, Japanese first satellite verification program MVP will be performed with domestic and foreign investigators. MVP will be continued during mission life of MOS-1. MOS-1 data will be sold to general users, while MOS-1 data are free of charge when these data will be used for the MVP.
National Space Development Agency of Japan(NASDA) conducted SAR-580 experiment from October to November, 1983 in Japan by using synthetic aperture radar (SAR) with variable parameters such as incidence angle, frequency and polarization mounted on an aircraft Convair 580 owned by Canada Centre for Remote Sensing (CCRS). The purposes of this experiment are to evaluate parameters of SAR mounted on Japanese Earth Resources Satellite-1 (ERS-1) to be launched in 1991, to develop calibration and processing method, to evaluate effectiveness of SAR in various application fields and to study optimum SAR parameters for future spaceborne SAR. In order to accomplish these objectives, about 100 scenes have been digitally processed by autofocusing method which has been developed for this experiment and quantitative comparison of SAR images with different parameters has been made for various targets in several test sites. As a result, effect of SAR parameters (off-nadir angle, frequency, polarization, signal to noise ratio, etc.) on SAR imagery has been clarified. In this paper, processing and evaluation methods, results of evaluation of SAR parameters will be presented.
The reactor No.4 of the Chernobyl Nuclear Complex exploded on 26 April 1986. The importance is that the accident brings the radiative materials into the environments. Because of the specialty of nuclear problems to human body, anybody and everbody has the right to know the condition of the nuclear matters. This report may serve such a request a little. NOAA/AVHRR and Salyut/KATK-140 imageries show the land cover condition of the wide area around the nuclear complex. Landsat TM image acquired on 29 April 1986 informs us the thermal condition of the exploded reactor and suggests the heavy deposition area. Landsat TM image on 26 April 1985, before the accident, shows the normally operated condition in the reservoir. Also Spot HRV 10 meter resolution image exhibits the planimetric configuration of the complex.
Recently, various types of national land information have been consolidated. The image information from Landsat is said to be useful in comparing and combining with existing statistical information, minor regional information, and digital national land information concerning natural and social conditions, particularly in regional analysis. This paper describes the two methods of regional analysis, (1) by applying trend surface analysis to land-cover classification data and land productivity data, and further (2) by combining the trend surface analysis of land productivity data and land-cover classification image, for the central part of the Kanto plain. As a conclusion, the regional feature of the study area is identified clearly, and this work will be a step for developing more proper method concerning the use of remote sensing data for regional analysis in the future.