Numerical simulations of winter cold damage to citrus fruits using the WRF model
To numerically assess winter cold damages of citrus fruits, a cold duration of sub-zero temperature was simulated using a high resolution configuration (500 m horizontal grid spacing) of the WRF numerical weather prediction system. Japanese citrus is often cultivated on slopes made of a small hill and a valley. Hence, a high resolution spatial configuration is needed to simulate cold durations at complex micro-topographies. In this study, detailed cold duration maps for sub-zero temperatures were produced to assess the spatial difference of cold duration, as an example of a winter cold surge attack in west Japan in 2011. Our findings suggest that the recorded temperature (by automatic observation of the Japan Meteorological Agency), which was observed at a flat coastal plain, may underestimate cold damage risk for citrus fruit on narrow slopes, valleys and hilly areas.