Many researches regarding the relationship between the solar activity and weather have been undertaken by many authors such as H. H. Clayton, S. Fujiwhara and others. But, most of them discussed mainly the relationship between the solar activity and the temperature or pressure at a single station, and their results often contradicted each other. This is due partly to the fact that most of them failed to take physical laws into account and partly to the failure of analysis from the global stand-point.
Presented in this paper are the existence and mode of the 5-month oscillatory temperature change in the Northern Hemisphere and a definite relationship between the solar activity and the oscillation. The thermal budget in the earth's atmosphere is discussed for a simple model in relation to the oscillation. Obtained results are as follows:
(1) The 5-month periodicity is found in the monthly course of the sunspot number as well as in the temperature-and pressure-change, the latter undergoing the same change as the former, as far as the amplitude is concerned. The phase difference of the 5-month periodicity between the solar activity and the pressure in the Northern Hemisphere may be divided into the two groups: the one with the same mode as the solar activity, the other not so. The zone of in-phase with the solar activity mentioned above is found near action centers of the atmosphere such as Siberian and North American anticyclone, the zone of out of-phase is encircling the lower latitude area. The location of the nodal line is oscillating following the change of the sunspot number.
(2) The thermal budget in the earth's atmosphere is discussed by making use of the idea of the great turbulence after Ångstrom, and our conclusion is: The periodic changes of the atmospheric temperature with a period of 5-month may be attributed to the periodic change of the austausch coefficient in the atmosphere, as far as the order of magnitude is concerned, but not to the variation of the solar constant.