A new index to project a crop production, ACI(Agricultural Abnormal Climate Index) based on the projection of weather conditions, has been developed. The conceptual framework of ACI was defined as impacts of high temperature, cold surge, drought, sunshine duration period and gale. The daily observed data for the period of 1975 to 2013 has been investigated to fine a relationship with rice production. The observed meteorological data includes temperature, precipitation, wind speed and sunshine duration. And the target research area has been limited to Chungcheongnam-do and Jeollanam-do. These two provinces are the largest rice production regions in Korea.
The first step to develop ACI is started to judge a criteria value of each meteorological factor to rice production damage. The critical meteorological factors have different units or dimensions, such as temperature, precipitation, wind speed and sunshine duration. A normalization technique has applied to the distribution of each meteorological factor to merge each other for ACI as the second step. Thus, the mean of normalized variable is 0 together 1 as standard deviation. Then, as third step, the impact of each meteorological variable has judged on the categories of standard deviation values. If any of meteorological index exceed criteria, it has defined as “occurrence of abnormal climate to damage” on the rice production. Finally the ACI has generalized to apply to different regions, in which the criteria values are no longer the same, by setting the ACI as 100 so that a damage may expected when the ACI value exceeds 100. Otherwise, there is no impact from the selected meteorological factor.
The relationship between rice production and ACI in Chungcheongnam-do and Jeollanam-do has been investigated respectively. The results show that the coefficient of correlation between ACI and rice production is ?0.4 and ?0.3 in Chungcheongnam-do and Jeollanam-do, respectively. The negative relationship means the rice production has marked less than normal with high ACI value and vice versa for the small ACI value. It has been observed that the impact of heat wave has increased and that of cold surge has decreased during 1980‘s to 2000’s. And impact of shortage of sunshine duration has increased conspicuously until 2000‘s.
The developed ACI has applied to provide a future prospective of rice production at the beginning of 2014 with the projection of long-term weather from Jan. 1st to the end of Oct. ,2014. The long-term climate projection has made with the meteorological condition at the time point of Jan. 1st to 5th, 2014 as initial condition and the observed SST and Sea Ice anomalies as boundary condition for 10 month integration. The climate model is the GME, uniform icosahedral-hexagonal grid global model, used as operational global numerical weather prediction model of the German Weather Service. The estimated ACI is 0 estimated results of this long-term projection of weather for 2014 at the beginning of 2014. It represents there is no meteorological event to damage to rice production. Accordingly, we may expect a good rice production in 2014.