Middle Atmosphere Program

The middle atmosphere, which extends from the tropopause at an attitude of 10-15 km to the lower thermosphere at about 120 km, has remained inaccessible to observation, and thus poorly understood, for many years. However, it is now realized that the middle atmosphere is an important part of our environment which we must understand. Weather and climate may be affected by the middle atmosphere, which is disturbed from below through various natural and artificial processes and from above through precipitating particles, etc. of solar origin. Pollution from man's activities may upset the chemical balance in the middle atmosphere, resulting in increased health hazards to all life. The Inter-Union Special Committee on Solar-Terrestrial Physics (SCOSTEP) has proposed the Middle Atmosphere Program (MAP) as an international scientific project to increase our understanding of this important region. The necessary observational techniques, largely of a remote sensing type, are currently available, as are largs computers necessary for the data analysis and theoretical support. Well coordinated observations will be essential in the middle atmosphere program because of the comolex coupling between chemical, transport, and radiative processes. In Japan a Working Group for MAP has been established by the Science Council of Japan, and the planning for MAP is now under way.