CLIMATE CHANGES BETWEEN TWO STANDARD PERIODS IN MONTENEGRO (1961-1990 AND 1991-2020) USING THE THORNTHWAITE MOISTURE INDEX
Authors:   University of  Montenegro, Faculty of Philosophy, Department of Geography, Nikšić, Montenegro, Mihajlović Jovan , Burić Dragan ,   University of  Montenegro, Faculty of Philosophy, Department of Geography, Nikšić, Montenegro, Penjišević Ivana ,   University of Priština in Kosovska Mitrovica, Faculty of Sciences and Mathematics, Kosovska Mitrovica, Serbia, Dragojlović Jovan ,   University of Priština in Kosovska Mitrovica, Faculty of Sciences and Mathematics, Kosovska Mitrovica, Serbia, Doderović Miroslav ,   University of  Montenegro, Faculty of Philosophy, Department of Geography, Nikšić, Montenegro
Published: February 2025

One of the models for differentiating climates in each area is the Thornthwaite Climate Classification (TCC). To analyze climate changes in Montenegro, using the criteria underlying the TCC, this study aims to classify the country’s climate across two standard climatic periods: 1961-1990 and 1991-2020. Using the Thornthwaite Moisture Index (PE), a bioclimatic delineation of regions with varying degrees of moisture in Montenegro was first conducted for the entire period (1961-2020), and subsequently for the two aforementioned subperiods (1961-1990 and 1991-2020). The study utilized air temperature and precipitation data from 18 meteorological stations (MS). All calculations were performed on a monthly basis using the PAST 4.13 software package, while the maps were created using QGIS 2.8.1. For mathematical modeling of the cartographic representation of the Thornthwaite climate classification, the Inverse Distance Weighted (IDW) geostatistical interpolation method was applied. The results, spanning a 60-year period, indicate that the Thornthwaite Moisture Index (PE) values range from 631.5 (MS Crkvice), corresponding to a humid (A) climate, to 95 (MS Pljevlja), indicating a humid (B) climate. The majority of meteorological stations in Montenegro exhibit values of this index that classify them within the A climate. The average RE value across the 18 meteorological stations for the 60-year period is 198.3, indicating that Montenegro’s climate was generally humid overall. Based on PE values, the lowest effects were observed at stations in the northern and northeastern regions of Montenegro, as well as in the far southeast, while the highest effects were recorded at stations in the southwestern and western parts of the country. This can be linked to the spatial distribution and precipitation patterns across Montenegro’s territory. The bioclimatic classification based on PE for the two subperiods reveals certain climate changes in Montenegro. Specifically, the A climate was represented at 66.7% of meteorological stations during the first period (1961-1990) and at 61.1% during the second period (1991-2020). Conversely, the B climate was represented at 33.3% of stations in the first period and at 38.9% in the second, indicating a slight aridification of the climate in the latter subperiod. Sub-humid (S), semi-arid (D), and arid (E) climates were not observed at any of the meteorological stations included in the analysis.