Potential distribution of the tiger mosquito Aedes albopictus in Northern Italy derived from reconstructed MODIS Land Surface Temperature maps

We developed an innovative methodology for the reconstruction of MODIS Land Surface Temperature (LST) time series, and derived temperature indicator maps to describe the potential distribution areas for the invasive tiger mosquito Aedes albopictus, a vector of several human diseases. The distributional limit of this species in temperate areas is determined by a minimum January mean temperature (JanT, winter egg survival), a minimum annual mean temperature (AnnT, adult survival) and a number of minimum growing degree days (life developmental cycle). As input we used more than 11,000 daily MODIS LST maps from 2000 to 2009 which we reconstructed in an Open Source GIS framework (GRASS GIS) on a Linux cluster in order to fill gaps originating from clouds in the LST maps. The average maps were subjected to thresholding in order to obtain binary maps indicating habitat suitability. All maps were superimposed, achieving a final integrated map showing the risk of potential distribution of Ae. albopictus. This map was validated with entomological field records of known invasion. The maps indicates new areas that may be colonized in the near future: Ae. albopictus could expand its distribution towards northern latitudes and higher altitudes, increasing the area at risk of mosquito-borne diseases.