Is April really the month with the most changable weather?
- Authors: Edo Đuvelek, Nejc Bezak, Mojca Šraj
- Citation: Acta hydrotechnica, vol. 29, no. 51, pp. 73-88, 2016.
- Abstract: The paper presents an analysis of weather variability in Slovenia. Data from eight meteorological stations in the period from 1980 to 2014 was used in this study. The main aim of this research was to determine whether April is the month with the largest percentage of capricious days in a year. Results indicate that differences among the number of capricious days in April and the number of capricious days in other months are not significant. Moreover, results indicate that the month with the largest number of capricious days is actually June at all the analysed stations, with the exception of the Portorož station, where the most capricious days were detected in May. Mann-Whitney test results show that April is similar to May, August and September in terms of the percentage of capricious weather. Mann-Whitney test was also used to determine the impact of climate change on weather variability in Slovenia. A comparison between 5-year periods from 1980 to 2014 was carried out. Results indicate that generally differences between consecutive 5-year periods were not statistically significant. The data was further analysed using the χ2 test. This test showed that the distribution of rainy, sunny and capricious days within the 5-year periods is generally non-uniform. The exceptions are precipitation days in the period from 2010 to 2014, for all analysed stations, where the distribution of rainy days throughout the year was uniform.
- Keywords: precipitation, solar radiation, capricious days, statistical tests, monthly distribution of capricious days
- Full text: a29ed.pdf
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