Spatial Coherence of Mean Annual Air Temperature and Local Day-to-Day Temperature Variability across Contrasting Environmental Settings
- Authors: Ognjen Bonacci, Ana Žaknić-Ćatović, Tanja Roje-Bonacci
- Citation: Acta hydrotechnica, vol. 39, no. 70, pp. 47-65, 2026. https://doi.org/10.15292/acta.hydro.2026.04
- Abstract: This study investigates the long-term behavior of mean annual air temperature and Day-to-Day (DTD) temperature variability across nine climatological stations representing three contrasting environmental settings: continental urban environments, the Istrian Peninsula, and Adriatic islands. The objective was to evaluate the spatial coherence of long-term temperature change while examining the extent to which local environmental characteristics influence short-term temperature variability. Mean annual air temperature exhibits a statistically significant increase at all stations and exceptionally strong inter-station correlations within each environmental setting, indicating a dominant regional-scale climate signal. In contrast, DTD variability displays considerably weaker spatial coherence and generally lacks statistically significant long-term trends, reflecting a stronger influence of local climatic and environmental factors. Urban stations exhibit relatively stable DTD behavior despite pronounced warming, whereas smaller urban centers demonstrate greater variability. Within the Istrian Peninsula, marked contrasts are observed between coastal and inland locations, while the Adriatic islands display remarkably homogeneous mean annual air temperature trends but locally distinct DTD characteristics despite their common maritime setting. These findings indicate that mean annual air temperature primarily reflects regional-scale climatic forcing, whereas DTD variability provides insight into local climatic stability and short-term atmospheric processes. The study demonstrates that analyses based solely on mean annual air temperature may overlook important aspects of local climate variability and highlights the value of DTD variability as a complementary metric for understanding climate change across contrasting environmental settings.
- Keywords: Air temperature, Day-to-Day temperature variability, urban environmental setting, small island setting, the Istrian Peninsula.
- Full text: a39ob.pdf
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