How Has Aridity Changed at a Fir (<i>Abies Borisii-Regis</i>) Forest Site in Central Greece during the Past Six Decades?

Abstract

Aridity monitoring is critical in forestry as it may affect forest growth, species diversity, and treeline shift. A widely used approach to assess the status of and changes in aridity is the aridity index (AI), defined as the ratio of precipitation (P) to potential evapotranspiration (PET). This study investigates the temporal change in the aridity index (AI) at a fir forest site between two distinct climatic periods: 1961–1990 and 1991–2020. To that end, long-term time series of mean monthly air temperature and total monthly precipitation from a forest meteorological station (1180 m a.s.l.) were collected and processed. Furthermore, the PET was estimated using a parsimonious parametric model based on a simplification of the Penman–Monteith formula. The results indicated that AI values slightly changed between the two considered climatic periods, while the climate was classified as humid and remained unchanged.

Keywords

• aridity index
• forest meteorological station
• climatic zone
• potential evapotranspiration
• parametric model