Nature of extreme precipitation over Ukraine in the 21st century

V. F. Martazinova; O. Shchehlov

doi:10.31481/uhmj.22.2018.04

V. F. Martazinova
O. Shchehlov

DOI: https://doi.org/10.31481/uhmj.22.2018.04

Keywords: extreme precipitation, climate, climate change, precipitation rates, precipitation regime

Abstract

The article examines the state of precipitation over the territory of Ukraine over recent decades. Through the example of central months of the seasons differences in monthly and average daily precipitation amounts for the period of 2000-2014 are shown. Within the most territory of Ukraine summer precipitation is almost twice as high as spring and autumn one. During all seasons the greatest amount of precipitation is observed in the Carpathian region. Distribution of average long-term precipitation values over the rest of the territory coincides in spring, summer and autumn: the highest precipitation values are observed in the western and north-western parts and decrease to the south-east.

The article studies a yearly precipitation rate at low-land and mountain meteorological stations. It proposes to separate criteria of precipitation extremality depending on the regions. All extreme daily precipitation can be divided into the following categories: > 20-30 mm / day, > 30-50 mm / day, > 50 mm / day. Each category of extreme precipitation has its a certain economic risk, but the third class can cause not only economic risks, but also risks associated with human life and activities. The distinct feature of the present-day precipitation consists in redistribution of precipitation in the middle of the months, when a daily precipitation rate increases together with intervals between heavy rains.

In order to analyze the changes of precipitation regime, the approach of dividing the rates of monthly precipitation amount by the rates of extreme and non-extreme precipitation is proposed. A comparative analysis of daily precipitation in different seasons and over different climatic periods was also carried out. The article studies the proportion of daily precipitation of up to 15 mm and the one exceeding 15 mm forming a part of monthly rates of precipitation over the territory of Ukraine. In January, rainfalls exceeding 15 mm make up from 5-10 % of the total amount of monthly precipitation, except the Carpathian region and the southwestern regions of Ukraine where those exceed 20-25 %. In spring, the amount of rainfalls increases and its percentage of the monthly precipitation amount is around 20 % over most of the regions. Until summer, the amount of rainfalls increases and in July its percentage is 50-70 %. Until autumn, the amount of those starts decreasing, however, the percentage of rainfalls is almost twice as high as in spring, and for most of the regions it is about 30-40 %. Such breakdown of the monthly precipitation rates into two components allows determination during a period in question of precipitation amounts we have each month.

The maximum daily precipitation amounts serve as an important indicator of the precipitation regime which shows the potential danger from extreme precipitation. For different regions the threshold values of the upper limit of rainfalls taken as a maximum daily value for the period of 2000-2014 differ. In winter and spring time, the limit of rainfalls amount per day usually hits 20-30 mm for the most territory of the country. At the same time there are certain areas where the limit values of the daily rainfalls rate reach 40-50 mm. The most significant rainfalls are observed in summer. Despite the fact that the territory of such rainfalls is quite patchy, nevertheless, those areas where precipitation rate over one day may reach 70 mm are the most vulnerable and have high risks for human life and activities. In autumn, the threshold values are 30-40 mm.

The breakdown of the rates of monthly precipitation amount into extreme and non-extreme ones allows determination in future of whether the precipitation regime changes because of extreme or non-extreme values. Also, in the long run, a comparative analysis of the rates of showers and weak rainfalls in the late 20th and early 21st centuries can be carried out and a tendency of precipitation regime seasonal change over the next decade can be obtained which will help us to identify vulnerable regions suffering from extreme precipitation rates.

References

1. Drought News August 2015. European Drought Observatory(EDO). Available at: http://edo.jrc.ec.europa.eu (accessed: 20.02.2018)

2. Alexander, L., Zhang, X., Peterson, T., Caesar, J. et al. (2006). Global observed changes in daily climate extremes of temperature and precipitation. Journal of Geophysical Research, 2006, 111. https://doi.org/10.1029/ 2005JD006290

3. Stepanenko, S.M, Polevoy, A.M., Demyanyuk, O.S., Dronova, O.O. (2014). Changes in rainfall regime in Ukraine. Ahroekolohichnyi zhurnal [Agroecological journal], 2, 10-17. (In Ukr.).

4. Klein Tank, A., Können, G. (2003). Trends in indices of daily temperature and precipitation extremes in Europe, 1946-99. Journal of Climate, 16, 3665-3680.

5. Osadchy V.I., Babichenko V.M. Dynamics of extreme meteorological phenomena in Ukraine. Ukrayinsʹkyy heohrafichnyy zhurnal [Ukrainian Geographical Journal], 2012. no. 4. pp. 8-14. (In Ukrainian)

6. Martazinova, V.F., Ivanova, O.K. (2010). The modern climate of the Kiev region. Kyiv: “AVERS” Publ. (In Ukr.).

7. Martazinova, V.F., Ivanova, E.K., Shcheglov, A.A. (2016). The tendency of modern temperature and humidity regime of Ukraine to abnormally dry and sultry atmospheric processes in the summer season. Naukovi pratsi UkrHMI [Proceedings UHMI], 268, 15-24. (In Russ.).

8. Martazinova, V.F., Sverdlik, T.A. (2001). Changes of large-scale atmospheric circulation during the XXth century and its influence on weather conditions and regional circulation in Ukraine. Ukrayinsʹkyy heohrafichnyy zhurnal [Ukrainian Geographical Journal], 2, 28-34. (In Russ.).

9. Martazinova, V.F., Ivanova, O.K. (2006). Zminy velykomasshtabnoi tsyrkuliatsii atmosfery ta ikh vplyv na rehionalnu tsyrkuliatsiiu i pohodni umovy [Changes of the large-scale atmospheric circulation and their impact on regional circulation and weather conditions]. In: V.M. Lipinsky, V.I. Osadchy, V.M. Babichenko (Eds). Stykhiini meteorolohichni yavyshcha na teritorii Ukrainy za octannie dvadtsiaterichia (1986-2005 rr.) [Natural spatial phenomena in the territory of Ukraine during the last twenty years (1986-2005)]. Kyiv: "Nika-Center". (In Ukr.).

10. Martazinova, V.F., Bakhmutov, V.G., Chayka, D.Yu. (2006). The influence of global warming on the change in large-scale atmospheric circulation and the formation of anomalous weather conditions in Ukraine. Dopovidi NAN Ukrayiny [Reports of the National Academy of Sciences of Ukraine], 2, 105-110. (In Russ.).

11. Brands, S., Manzanas, R., Gutie´rrez, J.M. (2012). Seasonal Predictability of Wintertime Precipitation in Europe Using the Snow Advance Index. American Meteorological Society, 25, 4023-4028.

12. Van den Besselaar, E.J.M., Klein Tank, A.M.G, Buishand, T.A. (2013). Trends in European precipitation extremes over 1951-2010. International Journal of Climatology, 33(12), 2682-2689.

13. Efimov, V.A., Ivus, G.P., Nazmudinova, E.N. (2008). To the question of the formation of spring droughts in the territory of Ukraine. Meteorolohiya, klimatolohiya ta hidrolohiya [Meteorology, climatology and hydrology], 50, 64-70. (In Russ.).

14. Matygin, A., Ivanov, S., Ivus, G., Palamarchuk, J. (2010). Changes in the precipitation and runoff regimes over the Eastern Europe. EGU General Assembly Conference Abstracts. Vienna, Austria, vol. 12, pp. EGU2010-8087.

15. Łupikasza, E, Hansel, S, Matschullat, J. (2010). Regional and seasonal variability of extreme precipitation trends in southern Poland and central-eastern Germany 1951-2006. International Journal of Climatology, 31, 2249-2271.

16. Maraun, D., Osborn, T., Rust, H. (2011). The influence of synoptic airflow on UK daily precipitation extremes. Part I: Observed spatio-temporal relationships. Climate Dynamics, 36, 261-275.

17. Nastanova po sluzhbi prohnoziv ta sposterezhen pro nebespechni ta stykhiini yavyshcha pohody [Guide to the service of forecasts and warnings on dangerous and natural weather phenomena]. (2003). Kyiv: State Hydrometeorological Service. (In Ukr.).

18. Agel, L., Barlow, M., Qian, J.H., Colby, F., Douglas, E., Eichler, T. (2015). Climatology of Daily Precipitation and Extreme Precipitation Events in the Northeast United States. Journal of Hydrometeorology, 16(6), 2537-2557.

19. Martazinova, V.F., Savchuk, S.V., Vitvitskaya, I.V. (2007). The state of the daily air temperature and daily precipitation of the winter season in the twentieth century in Kiev. Naukovi pratsi UkrNDHMI [Proceedings UHMI], 256, 7-18. (In Russ.).

20. Hoerling, M., Eischeid, J., Perlwitz, J., Quan, X.W., Wolter, K. (2016). Characterizing recent trends in U.S. heavy precipitation. J. Climate, 29(7), 2313–2332.

21. Alexander, L.V., Zhang, X., Peterson, T.C. et al. (2006). Global observed changes in daily climate extremes of temperature and precipitation. J. Geophys. Res. Atmos., 111, 1–22.

22. Martazinova, V.F., Sologub, T.A., Ivanova, O.K. (1997). Long-term forecasting of the average monthly temperature of air and monthly amount of precipitation for the territory of Ukraine. Zb. Systemni doslidzhennya ta modelyuvannya v zemlerobstvi [System Research and Modeling in Agriculture]. Kyiv: “Agroprom”, pp.17-28. (In Ukr).

23. Martazinova, V.F., Ivanova, E.K. (2011). Classification of synoptic processes by the field –etalon method and its application in the long-term weather forecast. Trudy nauchnogo seminara “Problemy i dostizheniya dolgosrochnogo meteorologicheskogo prognozirovaniya” [Proceedings of the scientific seminar "Problems and achievements of long-term meteorological forecasting”], October 5-7. Kiev: “Nika-Center”, pp. 40-46. (In Russ.).

24. Bagrov, N.A. (1965). O raspredelenii mesiachnykh sum osadkov [On the distribution of monthly precipitation]. Trudy TSIP [Proceedings Central Institute of Forecasts], 139, 3-21. (In Russ.).

25. Yudin, M.I. (1972). K ispolsovaniyu giperbolicheskikh tangensov normirovannykh anomaliy osadkov v ststisticheskikh prognozakh [On the use of hyperbolic tangents of normalized precipitation anomalies in statistical forecasts]. Trudy GGO [Proceedings Main Geophysical Observatory], 273, 157-165. (In Russ.).

26. Alexander, L.V. (2016). Global observed long-term changes in temperature and precipitation extremes: A review оf progress and limitations in IPCC assessments and beyond. Weather and Climate Extremes, 11, 4-16.