Abstract
Thailand has the extreme dry season and rainy season because of the tropical monsoon climate. They have suffered from droughts and floods almost every year and both have caused much damage on agriculture. The objective of this study is to estimate the effect of precipitation fluctuation on production of rice and maize in north Thailand. The statistical analysis using agricultural data shows what factor is determinant for production fluctuation of each crop. The correlation analysis between SPI, which is a simple indicator of precipitation fluctuation, and fluctuation of crop production indicates that there are some provinces where yield fluctuation of crop grown in rain-season shows positive correlation with SPI and harvested area fluctuation shows negative correlation with SPI. It also shows that in some provinces, planted area of rice grown in dry season depends on precipitation fluctuation.
