Figure 3. Distribution map of climatic variables in Japan.

Mesh climatic data of 380,000 one-kilometer mesh areas have been shown. The fill in the mesh areas indicates (A) annual mean temperature, (B) annual mean solar radiation, (C) annual total sunshine duration, and (D) effective day length at 4000 lx. Annual mean temperature tends to be relatively low in Northern Japan, while annual mean solar radiation, annual total sunshine duration, and effective day length at 4000 lx tend to be relatively low in the northern areas along the Japan Sea.