DIURNAL VARIATION OF THE LOCAL AIR-PRESSURE SYSTEM IN THE URBAN TOKYO

We discuss the diurnal variation of the air-pressure system in the urban Tokyo. In summer, the pressure drop in the morning is larger in the suburban Tokyo, and in the afternoon is larger in the downtown Tokyo. After sunset, firstly the pressure rise is larger in the downtown Tokyo, thereafter is larger in the suburban Tokyo. In winter, the diurnal variation is almost opposite. Commonly, while the area-averaged air-pressure drops, the pressure drop is firstly larger in the downtown; while rises, the pressure rise is firstly larger in the suburban. The development of local cyclones/anticyclones and semi-diurnal atmospheric tides also contribute to these diurnal variations