STUDIES ON THE DURATION OF DROUGHT FROM THE AGRICULTURALVIEWPOINT

Abstract

Recently, a lot of researches on predicting climatic change have been conducted, and the effects of climatic change on agriculture have been estimated from the viewpoint of agricultural meteorology. Quantitative evaluation of this effect is not, however, easy, since improvement of yields are related to multiple factors, including plant breeding and improvement of irrigation technology. This paper considers the relationship between precipitation and agricultural characteristics, and more specifically, an index that indicates the effect of drought on the yield. First, drought and pluvial years are defined here by the amount of precipitation, and the characteristics of both are discussed. Next, duration of drought is defined in three ways is considered. It could be concluded that duration of drought is an important index for predicting agricultural yields.