自然土壌における温度年変化の推定

The equation to forecast the annual temperature variation of natural soil is derived from the author's investigation. It is determined on referring the average temperature over the diurnal variation. It is expressed as a harmoinc(2.1).
A procedure is proposed to analyse the harmonic. It is a method to solve the simultaneous equation(2.8).
The solutions are transformed into the amplitude and the phase lag in the harmonic. In the case of the annual variation, the terms higher than third order in the harmonic can be neglected since their effect is small. The special discussion is focused on the first harmonic. Judging from the results of these analysis, the method produces a good approximation.