Aridity (Ar) - Growing season climatic moisture deficits (May through August) were derived from the ecodistrict precipitation and potential evapotranspiration values calculated using the 1961-1990 30-year climate normals (Agriculture and Agri-Food Canada 1997). Risk ratings for aridity classes are given in Table 3.
Le tableau 3 montre la classification du risque pour les catégories d’aridité.