Characteristics of time changes on rice production predicted by the MRI's CGCM

We estimate the time change of the rice production for every 10 years for a period of 100 years by using the MRI's CGCM containing the transient CO₂ experiment, and the crop model named SIMRIW. On this estimation by these models, we choose the `Koshihikari' as a representative cultivar and assume optimal cultivation technologies are adopted. Annual and summer seasons mean air temperature increase almost linearly, and become 2.0 to 3.0 degree C higher after 70 years, 3.0 to 4.0 degree C higher after 100 years, and these temperature changes are almost 1.0 to 2.0 degree C smaller than the predictions of previous studies. As a result of this, the cultivated area of `Koshihikari' is estimated to spread northward, and the yield in currently cultivated area is also simulated not to change toward a harsh condition for at least 100 years, under optimal cultivation technologies.