esent tendencies of annual cycle rainfall change in Ukraine
Abstract
Introduction. The precipitation regime, its amount and distribution throughout the year are an important component of the climate characteristics. This information is of exceptional importance in the planning and management of water resources.
The purpose of article is to present an expanded description of the annual cycle of atmospheric precipitation in Ukraine and to identify the most important features of its change over the period 1961-2020.
Data and methods. This paper examines the features of the annual cycle of atmospheric precipitation in the continental part of Ukraine. The research is based on data from climatological reference books at 153 weather stations across the country. Much attention is paid to the parameters of the harmonic analysis of the initial observation series in 1961-1990 and 1991-2020 and the residual series formed on their basis with changes in precipitation, primarily the amplitude and the phase of the annual harmonic, as well as its contribution to the total variance of monthly precipitation series.
Results. Changes in the repeatability of gradations of the amplitude of the annual harmonic of atmospheric precipitation are analyzed. A comparison of the statistics of the series of the annual harmonic amplitude and annual amplitude of atmospheric precipitation at weather stations of Ukraine during 1961-1990 and 1991-2020 is carried out. Changes in the statistical distributions of the repeatability of gradations of annual and semi-annual harmonics by their contribution to the total variance of rainfall annual cycle in Ukraine in different observation periods were considered. The repeatability of gradations of the timing of annual harmonic of atmospheric precipitation maxima in these periods is analyzed. Significant spatial heterogeneities in the distribution of annual and monthly precipitation amounts were found. Harmonic analysis also allowed us to identify important patterns within the annual cycle. The main role in seasonal fluctuations in monthly precipitation amounts is played by the annual, and less often - semi-annual harmonics. During the transition from the first observation period (1961-1990) to the second (1991-2020), the inverse relationship between the parts of the variance caused by these harmonics noticeably weakened (the coefficient of determination between the parameters and of the annual and semi-annual harmonics decreased from 0.876 to 0.661). At the same time, the slope of the linear relationships between these parameters significantly decreased (the coefficient of the linear regression equation changed from -0.771 to -0.47).
The scientific novelty. It has been established that the amplitude and phase structure of the annual harmonic, as well as the relative role of the annual and semi-annual harmonics of monthly precipitation in the current climate, have undergone significant changes. This is probably due to changes in the nature of atmospheric circulation over the entire Atlantic-European sector, although the influence of local climate-forming factors cannot be completely excluded either.
Practical significance. The identified changes in the phase structure and other characteristics of the annual harmonics of monthly precipitation series contribute to a better understanding of current trends in the evolution of the regional climate system in Ukraine and will be useful for long-term climate change forecasting.
Downloads
References
Vodchyts, O.G., Zatula, V.I. (2017). Fundamentals of meteorology and climatology. Kyiv, Ukraine, 360. [in Ukrainian]
Zatula, V.I. (2017). Identifying of the hidden periodicities of seasonal oscillations of meteorological variables on the territory of Volyn Polissya. Physical geography and geomorphology, 1(85), 101–105. [in Ukrainian]
Zatula, V. (2024). Complex assessing of aridity in Ukraine. Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology", (61), 180–192. https://doi.org/10.26565/2410-7360-2024-61-15. [in Ukrainian]
Zatula, V.I., Zatula, N.I. (2014). Harmonic analysis of seasonal oscillations of some meteorological variables on Ukrainian territory. Hydrology, hydrochemistry and hydroecology, 2(33), 98–103. [in Ukrainian]
Zatula, V.I., Zatula, N.I. (2017). Identifying of the hidden periodicities of seasonal oscillations of meteorological variables on the territory of Zhytomyr Polissya. Hydrology, hydrochemistry and hydroecology, 1(44), 114–120. [in Ukrainian]
Lipinsky V.M., Dyachuk V.A., Babichenko V.M. eds. (2003). Climate of Ukraine. Kyiv, Ukraine, 343.
Kholiavchuk, D.I. (2019). Regional climatology. Chernivtsi, Ukraine, 168. [in Ukrainian]
Blüthgen, J. (1966). General Climatic Geography. Berlin, Boston: De Gruyter. https://doi.org/10.1515/9783111440293. [in German]
Boucher, K.R. (1987). Europe, climate of. In: The Encyclopedia of Climatology. Ed. by John E. Oliver. New York, 355–367.
Chen, T.-C., Wu, K.-D. (1992). Semi-annual oscillation of the global divergent circulation. Tellus, 44A, 357–365.
Cui, D., Liang, S., Wang, D. (2021). Observed and projected changes in global climate zones based on Köppen climate classification. WIREs Climate change, 12(3), e701. https://doi.org/10.1002/wcc.701.
Fabiano, F., Meccia, V.L., Davini, P., Ghinassi, P. Corti, S. (2021). A regime view of future atmospheric circulation changes in northern mid-latitudes. Weather and Climate Dynamics, 2(1), 163–180. https://doi.org/10.5194/wcd-2-163-2021.
Gardner, A.S., Maclean, I.M.D., Gaston, K.J. (2020). A new system to classify global climate zones based on plant physiology and using high temporal resolution climate data. Journal of Biogeography, 47, 2091–2101. https://doi.org/10.1111/jbi.13927.
Gründemann, G.J., Zorzetto, E., van de Giesen, N., van der Ent, R.J. (2023). Historical shifts in seasonality and timing of extreme precipitation. Geophysical Research Letters, 50, e2023GL105200. https://doi.org/10.1029/2023GL105200.
Jaison, A.M., Gray, L.J., Osprey, S., Smith, A.K., Garcia, R.R. (2024). A momentum budget study of the semi-annual oscillation in the Whole Atmosphere Community Climate Model. Quarterly Journal of the Royal Meteorological Society, 150(763), 3544–3565. https://doi.org/10.1002/qj.4782.
Karwat, A., Franzke, C.L.E., Blender, R. (2022). Long-term trends of Northern Hemispheric winter cyclones in the extended ERA5 reanalysis. Journal of geophysical research: Atmospheres, 127(22), e2022JD036952. https://doi.org/10.1029/2022JD036952.
Kholiavchuk, D. (2022). Changes in the atmospheric circulation types over western Ukraine in the 20th-21st centuries. Bulletin of Taras Shevchenko National University of Kyiv, Geography, 3/4 (84/85), 39–45. https://doi.org/10.17721/1728-2721.2022.85.2.
Kottek, M., Grieser, J., Beck, C., Rudolf, B., Rubel, F. (2006). World map of the Köppen-Geiger climate classification updated. Meteorologische Zeitschrift, 15, 259–263. https://dx.doi.org/10.1127/0941-2948/2006/0130.
Mimić, G., Podraščanin, Z., Basarin, B. (2024). Change detection of the Köppen climate zones in Southeastern Europe. Atmospheric Science Letters, 25(11), e1270. https://doi.org/10.1002/asl.1270.
Navarro, A., Merino, A., García-Ortega, E., and Tapiador, F.J. (2025). Uncertainty maps for model-based global climate classification systems. Scientific Data, 12, 35. https://doi.org/10.1038/s41597-025-04387-0.
Rousi, E., Selten, F., Rahmstorf, S., Coumou, D. (2021). Changes in North Atlantic Atmospheric Circulation in a Warmer Climate Favor Winter Flooding and Summer Drought over Europe. Journal of Climate, 34, 2277–2295. https://doi.org/10.1175/JCLI-D-20-0311.1.
Shangguan, M., Wang, W. (2022). The semi-annual oscillation (SAO) in the upper troposphere and lower stratosphere (UTLS). Atmospheric Chemistry and Physics, 22(14), 9499–9511. https://doi.org/10.5194/acp-22-9499-2022.
Shimabukuro, R., Tomita, T., Fukui, K.‑ichi. (2023). Update of global maps of Alisov’s climate classification. Progress in Earth and Planetary Science, 10:19. https://doi.org/10.1186/s40645-023-00547-1.
Song, Y.H., Chung, E.‐S., Ayugi, B.O. (2025). CMIP6 GCMs projected future Koppen‐Geiger climate zones on a global scale. Earth's Future, 13, e2023EF004401. https://doi.org/10.1029/2023EF004401.
Wilks, D.S. (2006). Statistical methods in the atmospheric sciences. 2nd edn. Amsterdam, 630.
Zatula, V.I. (2018). Decomposition and modelling of the annual cycle of meteorological variables in the Ukrainian Carpathians. Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology", 49, 95–106. https://doi.org/10.26565/2410-7360-2018-49-08.
This work is licensed under a Creative Commons Attribution 4.0 International License.
