Source of meteorological data
ECMWF high resolution model is presently the best meteorological model which covers all Europe. It is updated every 6 hours and combines information from different national centers in Europe. Covered domain goes in longitude from 12°W to 40.5°E and in latitude from 30°N to 60°N. The horizontal resolution is 0.125° (about 12.5km). The vertical resolution is 25 levels unevenly distributed, increasingly flat with altitude, from the soil to 100 hPa.
The calculation of the weekly activity of the previous week is based on the average of all readings of that week.
In order to improve existing maps by taking into account the influence of the biotope with more accuracy, static parasite suitability maps have been constructed by experts in Geographic Information Systems (GIS). For that purpose, LANMAP has been used. It is a landscape classification of Pan-Europe with 4 hierachical levels; using digital data on climate, altitude, parent material and land use as determinant factors. More precisely, the Climatic European Landscape Classification Layer has been used. It defines the climates encountered over Europe into 15 climate categories. In the context of Fleatickrisk, these categories have been allocated to 4 biotope classes from the least to the most suitable for each tick species. A weighting has been attributed to each class for the calculation of activity and density indices.
Biotope weight maps have been computed on the meteorological grids. The biological activity is then built from:
Biological activity = f(temperature ECMWF output, relative humidity ECMWF output) × biotope weight
(f is given by matrix activity depending on parasite)
Matrices of activity for ticks and fleas
Index 100 means optimal biological conditions:
- Ticks: Questing for hosts and infesting hosts (taking a blood meal)
- Fleas: Optimal evolution from eggs to pupae in the environment.
Index 0 does not mean the death of the parasite, only a diapause (dormancy).