Figure 1.

Sigmoidal functions that are employed to relate A. albopictus suitability (ranging from 0 to 255) to climate predictor variables such as (a) annual precipitation, (b) January temperature and (c) summer temperature. This is carried out for model 2. For annual precipitation, suitability is dropped to zero when rainfall is lower than 450 mm, and maximum (255) when precipitation is higher than 800 mm; for January temperature, the suitability is zero when temperatures are lower than −1°C, and maximum when temperatures are higher than 3°C; for summer temperature, the suitability is zero when temperatures are lower than 15°C and higher than 30°C, and maximum between 20°C and 25°C.