Assessment of River Water Inflow into the Sasyk Estuary-Reservoir According to RCP4.5 and RCP8.5 Climate Change Scenarios for 2021-2050


Keywords: Sasyk estuary, water balance, freshwater inflow, climate change scenarios

Abstract

The paper relevancy is determined by the need to substantiate the feasibility of restoring the ecosystem of the Sasyk estuary after its transformation into a reservoir (1978) and the unsuccessful desalination by the Danube waters for irrigation purposes. The paper is aimed at assessment of the possible inflow of fresh water to the Sasyk estuary from the Kohylnyk and Sarata rivers and their role in the formation of fresh water balance in the first half of the 21st century according to the climate change scenarios RCP4.5 and RCP8.5. The main calculation method is the ‘climate-runoff’ model, which uses meteorological data as input data. Estimates of freshwater inflow into the estuary-reservoir are provided for various calculation periods: before 1989 (before the beginning of significant climate change in the North-Western Black Sea Region); in the period of 1989-2018 according to the hydrometeorological observations; in 2021-2050, according to the averaged data from 14 runs of scenarios RCP4.5 and RCP8.5 under the EVRO-CORDEX project. Estimates of the average long-term values of freshwater inflow in natural conditions and the conditions transformed by water management activity were obtained for each calculation period. It is found that owing to changes in the regional climate for the period of 2021-2050, the total inflow of freshwater from rivers to the estuary in natural conditions will decrease by 23.5 % (by RCP4.5) and by 38.5 % (by RCP8.5) in comparison with the reference period (before 1989). Taking into account the impact of artificial reservoirs, the reduction in the river runoff will be 52.1 % (by RCP4.5) and 64.7 % (by RCP8.5). It is defined, that in case of renaturalization of the Sasyk reservoir into the estuary and the water inflow cut-off from the Danube river, the changes in climatic conditions expected in the first half of the 21st century, combined with water management activity, will result in the increased deficit of annual freshwater balance of the Sasyk reservoir up to 62 % under the RCP4.5 scenario and up to 75 % under the RCP8.5 scenario compared to the period before the emergence of climate change (before 1989). This change must be considered in scientific substantiation of the project on a reversion of the Sasyk Reservoir to the original status of the estuary to ensure such conditions of water exchange with the sea (for compensation of the water balance deficit), which will prevent the long-term trend of salinization.

Author Biographies

Nataliia S. Loboda
Odessa State Environmental University, Odessa
Yurii S. Tuchkovenko
Odessa State Environmental University, Odessa
Mykhailo О. Kozlov
Odessa State Environmental University, Odessa
Iryna V. Katynska
Odessa State Environmental University, Odessa

References

1. ACDTRM (Agentia constructui si dezvoltarea teritoriului a Republich Moldova), 2012. CPD.01.05-2012: Opredelenie gidrologicheskih harakteristik dlja uslovij Respubliki Moldova [Determination of hydrological characteristics for the conditions of the Republic of Moldova]. Kishinev, Moldova (in Russian).
2. Bloshl, G., Hall, J., Viglione, A. et al., 2019. Changing climate both increases and decreases Europian river floods. Nature 573, 108-111.
3. Didovets, L., Krysanova, V., Fred Fokko Hattermann, Maria del Rocio Rivas Lopez, Snizhko, S., Hannes Muller Schmied, 2020. Climate change impact on water availability, of main water rivers basins in Ukraine. Journal of Hydrology. Regional studies, 32 100761. doi:10.1016/j.ejrh.2020.100761.
4. Evans, J.P., 2011. CORDEX – An international climate downscaling initiative. 19th International Congress on Modelling and Simulation. Perth (Australia), 2705-2711.
5. Gopchenko, E.D. & Loboda, N.S., 2001. An evaluation of possible changes in the water resources of Ukraine under global warming conditions. Hydrobiological Journal, 37(5), 105-117. doi:10.1615/HydrobJ.v37.i5.90.
6. Gopchenko, E.D., Loboda, N.S., Ovcharuk, V.A., 2014. Hidrolohichni rozrakhunky [Hydrological calculations]. TES, Odesa, 484. (in Ukrainian).
7. Grebin, V.V., 2010. Suchasnyi vodnyi rezhym richok Ukrainy (landshaftno-hidrolohichnyi analiz) [The modern water conditions of Ukrainian rivers (landscapehydrological analysis)]. Nika-Centr, Kyiv, 316. (in Ukrainian).
8. IPCC (International Panel on Climate Change), 2014. “Chapter 2: Foundations of Decision Making”. In Climate Change 2014: Impacts, Adaptation, and Vulnerability. Contribution of Working Group II to the Fifth Assessment.
9. Ivanov, N.N., 1954. Ob opredelenii velichin isparjaemosti [Оndeterminationofthemagnitudeofvolatility]. Izv. MGO, 189-196. (in Russian).
10. Kaczmarek, Z., 1993. Water balance model for climate impact analysis. Acta Geophisica Polonica, 41 (4), 423-437.
11. Kushnir, D.V. & Tuchkovenko, Yu.S., 2020. Modeliuvannia minlivosti hidrolohichnikh kharakterystyk vodoimy Sasyk za riznikh variantiv ee funktsionuvannia [Modelling the variability of hydrological parameters of the Sasyk reservoir impoundment under various options of its operation]. Ukrainian hydrometeorological journal, 26, 116-129. doi:10.31481/ uhmj.26.2020.10. (in Ukrainian).
12. Loboda, N.S., 2005. Raschety i obobshhenija harakteristik godovogo stoka rek Ukrainy v uslovijah antropogennogo vlijanija [Calculations and generalizations of characteristics of annual runoff of rivers of Ukraine in the conditions of anthropogenic influence]. Ecology, Odessa, 208. (in Russian).
13. Loboda, N.S. & Gopchenko, E.D., 2006. Stokhastychni modeli u hidrolohichnykh rozrakhunkakh [Stochastic models in hydrological calculations]. Ecology, Odessa. 200. (in Ukrainian).
14. Loboda, N.S. & Gopchenko, E.D., 2016. Vodnyi rezhym ta hidroekolohichni kharakterystyky Kuialnytskoho lymanu [Water regime and hydroecological characteristics of Kuyalnytskyi Liman]. TES, Odesa (in Ukrainian).
15. Loboda, N.S. & Gryb, O.M., 2017. Hydroecological Problems of the Kuyalnyk Liman and Ways of Their Solution. Hydrobiological Journal, 53(6), 87-95. doi: 10.1615/HydrobJ.v53.i6.90.
16. Loboda, N.S. & Kozlov, M.О., 2020. Otsinka vodnykh resursiv richok Ukrainy za serednimy statystychnymy modeliamy traektorii zmin klimatu RCP4.5 ta RCP8.5 u period 2021- 2050 roky [Assessment of water resources of the Ukrainian rivers according to the average statistical models of climate change trajectories RCP4.5 and RCP8.5 over the period of 2021 to 2050]. Ukrainian hydrometeorological journal, 25, 93-104. doi:10.31481/uhmj.25.2020.09. (in Ukrainian).
17. Loboda, N.S. & Phan Van Chinnh, 2004. Statistical modelling and estimating the irrigation and man- made effect on annual runoff and water resources. GIS and Remote Sensing in Hydrology, Water Resources and Environment. (Proceedings of ICGRHWE held Tree Gerges Dam, Chine.). IAHS Publication 289 in the IAHS Series of Proceedings and Reports, 215-218.
18. Lozovitskyi, P.S., 2010. Vodni ta khimichni melioratsii gruntiv [Water and chemical land reclamation]. Publishing and printing center “Kyiv University”, Kyiv. 276. (in Ukrainian).
19. Lozovitskyi, P.S, 2013. Hidrolohichnyi rezhym ta otsiniuvannia yakosti vody ozera-vodoskhovyshcha Sasyk u chasi [Hydrology regime and water quality estimation of lake- reservoir Sasyk in time]. Magazine of Cartography 6, 146-170. (in Ukrainian).
20. Lyashenko, A.V. & Zorina-Sakharova, E.E., 2016. Gidrologo-gidrohimicheskaja harakteristika limana Sasyk i Sasykskogo vodohranilishha [Hydroecological and hydrochemical characteristics of the Sasyk Lagoon and the Sasyk reservoir]. Hydrobiological Journal, 52(6), 99- 109 (in Russian).
21. Snizhko, S., Kuprikov, І., Shevchenko, О., 2012. Ocenka izmenenija vodnogo stoka rek Ukrainy na osnove vodno-balansovyh modelej [Estimation of change of water runoff of rivers of Ukraine on the basis of water-balance models]. Physical Geography and Geomorphology, 66(2), 157-161. (in Russian).
22. Tuchkovenko, Yu.S., 2011. Sovremennyj gidrojekologicheskij rezhim vodohranilishha Sasyk i problemy ego rekonstrukcii v morskoj liman. Sovremennye problemy vodohranilishh i ih vodosborov. T. 1: Gidro- i geodinamicheskie processy. [The modern hydroecological regime of the Sasyk reservoir and the problems of its reconstruction into a sea liman. Modern problems of reservoirs and their catchments. Vol.1 Hydro and geodynamic processes]. Proc. International scientific and practical conference. Permian. 162- 167. (in Russian).
23. Tuchkovenko, Yu.S. & Loboda, N.S., 2014. Vodni resursy ta hidroekolohichnyi stan Tylihulskoho lymanu [Water resources and hydroecological conditions in Tiligulskyi Liman]. TES, Odessa. 278. (in Ukrainian).
24. Tuchkovenko, Yu.S. & Loboda, N.S., 2017. Vlijanie izmenenij klimata na strategiju vodnogo menedzhmenta lagun severo-zapadnogo Prichernomor’ja [Impact of Climate Change on Water Management Strategy for Lagoons in the North-Western Black Sea Region]. Proc. All- Ukrainian hydrometeorological congress with international participation. TES, Odesa. 312-313. (in Russian).
25. Vyshnevskyi, V.I., 2000. Richky i vodoimy Ukrainy. Stan i vykorystannia [Rivers and reservoirs of Ukraine. Condition and use]. Vipol, Kyiv, 375. (in Ukrainian).
Published
2021-07-18
How to Cite
Loboda, N., Tuchkovenko, Y., Kozlov, M., & Katynska, I. (2021). Assessment of River Water Inflow into the Sasyk Estuary-Reservoir According to RCP4.5 and RCP8.5 Climate Change Scenarios for 2021-2050. Journal of Geology, Geography and Geoecology, 30(2), 315-325. https://doi.org/https://doi.org/10.15421/112128