Spatial–temporal distribution of heavy precipitation over Ukraine during 1979-2019 according to the ERA5 reanalysis

  • A. B. Semerhei-Chumachenko
  • K. L. Slobodianyk
Keywords: reanalysis data, ERA5, heavy precipitation, extreme precipitation, elementary circulatory mechanisms.

Abstract

The paper presents the results of research of heavy and extreme precipitation in the form of rain (> 50 mm / 12 h) and snow (> 20 mm / 12 h) using the data from the atmospheric reanalysis ERA5 for the period of 1979-2019. According to the data of the European Centre for Medium-Range Weather Forecasts obtained through the numerical modeling and resulting from the data assimilation at the nodes of a regular grid with a spatial resolution of 0,25°×0,25°, there are 131 and 136 days with rain and snow during which precipitation intensity reached the criteria of meteorological phenomena of the 2nd and 3rd levels of danger. It was discovered that the last 40 years in Ukraine proved to have a tendency of an increased number of cases of heavy snowfall, and a slightly decreased number of heavy rains.

The research pays considerable attention to the spatial-temporal analysis of the frequency and intensity of heavy rainfall with consideration of geographical factors. It determines the seasonal course of heavy and extreme precipitation, the maximum and minimum values of which did not differ from the climatic standard values observed during meteorological observations. Rainfalls with precipitation rates of more than 50 mm over 12 hours were observed almost over the entire territory of Ukraine and the maximum frequency zones were detected over the Carpathian Mountains, Donetsk Ridge, Podolsk Upland, and the south-western part of the country. Heavy snowfalls with more than 20 mm precipitation over 12 hours mostly occurred in the Carpathian region. The analysis of the geographical distribution revealed a center with maximum values of rain intensity (120-133 mm over 12 h) off the coast of the Sea of Azov, and the heaviest snowfalls (34-38 mm over 12 h) mainly formed in the Carpathian region.

The paper established the types of elementary circulation mechanisms of Dzerdzeevsky’s synoptic classification of Northern Hemisphere atmospheric circulation. These types, when continuous in nature, resulted in a significantly increased precipitation in the form of rain and snow.

According to the reanalysis data, cases with the maximum rain intensity were found over the period of 23 to 27 July 2008 when a catastrophic flood was observed in the Ukrainian Carpathians. This fact indicates that the structure of the field of heavy precipitation over the territory of Ukraine was adequately reproduced by the respective model of the European Centre for Medium-Range Weather Forecasts.

References

Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part B: Regional Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. (2014.). Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA: IPCC.

Derzhavna sluzhba Ukrainy z nadzvychainykh sytuatsii [The State Emergency Service of Ukraine]. Available at: https://www.dsns.gov.ua/ua/Dovidka-za-dobu/111143.html (accessed: 11.09.2020). (in Ukr.)

Copernicus Climate Data Store. ERA5 hourly data on single levels from 1979 to present. Available at: https://cds.climate.copernicus.eu/ cdsapp#!/dataset/reanalysis-era5-single-levels?tab=form (Accessed: 10.03.20).

Humonenko, L.V., Zhuk, N.H., Savchenko, L.I. et al. (2019). Nastanova z meteorolohichnoho prohnozuvannia [Meteorological forecasting guide.] Kyiv. (in Ukr.)

Balabukh, V.O. et al. (2018). Extreme weather events in Ukraine: occurrence and changes. In: Sallis, P.J. (ed.). Extreme Weather. London, UK. IntechOpen, pp. 85-106.

Semerhei-Chumachenko, A.B. & Ozymko, R.R. (2019). Distribution of storm rains in the Transcarpathian region for the last twenty-years (1999-2018). Ukrayinsʹkyy heohrafichnyy zhurnal [Ukrainian Geographical Journal], 4(108), pp. 11-17. (in Ukr). https://doi.org/10.15407/ ugz2019.04.011

Lipinskyi, V.M., Diachuk, V.A. & Babichenko, V.M. (eds). (2003). Klimat Ukrainy [Climate of Ukraine]. Kyiv: Raevsky Publ. (in Ukr)

Babichenko, V.M. & Lipinskyi, V.M. (eds). (2006). Stykhiini meteorolohichni yavyshcha na terytorii Ukrainy za ostannie dvadtsiatyrichchia (1986-2005 rr.) [Extreme meteorologogical events in Ukraine 1986-2005]. Kyiv: Nika-Centr Publ. (in Ukr.)

Osadchy, V.I. & Babichenko, V.M. (2012). Dynamics of adverse meteorological phenomena in Ukraine. Ukrayinsʹkyy heohrafichnyy zhurnal. [Ukrainian Geographical Journal], 4, pp. 8-14. (in Ukr.) Available at: https://ukrgeojournal.org.ua/sites/default/files/UGJ-2012-4-08_0.pdf

Balabukh, V.O. (2008). Minlyvist duzhe sylnykh doshchiv i sylnykh zlyv v Ukraini [Variability of very heavy rains and heavy rainfalls in Ukraine]. Nauk. Pratsi UkrNDHMI [Scientific works of UkrSEHMI], 257, pp. 61-72. (in Ukr.)

Martazinova, V.F. & Shchehlov, A.A. (2018). [Nature of extreme precipitation over Ukraine in the 21st century]. Ukr. gìdrometeorol. ž. [Ukrainian hydrometeorological journal], 22, pp. 36-45. (in Russ.). https://doi.org/10.31481/uhmj.22.2018.04

Khokhlov, V.M., Umanska, O.V., El Hadri, Y. et al. (2017). [Identifying the possibility of using reanalysis data in research]. Tezy dopovidei 1th Vseukrainskoho hidrometeorolohichnoho zizdu z mizhnarodnoiu uchastiu [Theses of reports of the First All-Ukrainian Hydrometeorological Congress with International Participation], 22-23 March. Odesa, pp. 235-236. (in Ukr.)

European Centre for Medium-Range Weather Forecasts (ECMWF). Available at: https://www.ecmwf.int/ (Accessed: 10.03.2020).

Miguel Nogueira. (2020). Inter-comparison of ERA-5, ERA-interim and GPCP rainfall over the last 40 years: Process-based analysis of systematic and random differences. Journal of Hydrology, 583, pp. 1-17. https://doi.org/10.1016/j.jhydrol.2020.124632

Tymofeyev, V.E., Scheglov, A., Skorotyana, Yu. (2013). On the extreme summer precipitation in Ukraine over the last decades. Proceedings of the 7th European Conference on Severe Storms (ECSS2013). Helsinki, Finland.

Available at: https://www.essl.org/ECSS/2013/programme/ abstracts/144.pdf

Guide to Climatological Practices. WMO. 2018. No. 100, pp. 89-91. Available at: https://library.wmo.int/ doc_num.php?explnum_id=9868 (Accessed: 15.09.2020).

Kalendar' posledovatel'noy smeny ЕCM po periodam [Calendar of consecutive ECM changes by periods]. Available at: http://atmospheric-circulation.ru (Accessed: 20.04.2020). (in Russ.)

Published
2020-12-22
How to Cite
Semerhei-Chumachenko, A. B., & Slobodianyk, K. L. (2020). Spatial–temporal distribution of heavy precipitation over Ukraine during 1979-2019 according to the ERA5 reanalysis. Ukrainian Hydrometeorological Journal, (26), 50-59. https://doi.org/10.31481/uhmj.26.2020.04
Section
Meteorology and Climatology