Long-term meteorological data and isotopic composition in precipitation, surface water and groundwater revealed hydrologic sensitivity to climate change in East Ukraine^*

* Originally presented at the IAEA Symposium on Isotope Hydrology 2019, Vienna, Austria, 20–24 May 2019.

ABSTRACT

Our study focused on the incorporation of stable isotope ratios in water in climatic and hydrological observations to understand local hydroclimatic processes and determine basic hydrological sensitivity to climate change in East Ukraine. Long-term meteorological data from two stations at Kharkiv and Izyum showed that air temperature was significantly increased only for the cold period (November–April), while precipitation amount increased during all seasons. Applying two-component mixing model with stable isotope ratios in water, we determined that surface water in both regions was dominantly recharged by the cold precipitation. The highest share of cold precipitation contribution (∼79 %) was found in the river with the shortest water transit time. The isotopic signature of groundwater also indicated that water resources were mainly recharged during the cold period. Our findings reveal that basic hydrological sensitivity of the transboundary (Ukraine/Russian Federation) Seversky Donets River basin relates to hydroclimate changes mainly observed in November–April. We suggest that climate changes can influence surface water and groundwater but also the overall regional water availability that is highly dependent on the cold precipitation in these regions.

KEYWORDS:

• Climate change
• deuterium excess
• hydrogen-2
• isotope hydrology
• oxygen-18
• Ukraine

Acknowledgments

The authors are grateful to administration of Kharkiv Meteorological College (Kharkiv) and National Nature Park ‘Svyati Gory’ (Svyatogirsk) for assistance in sampling of precipitation and rivers.

Disclosure statement

No potential conflict of interest was reported by the author(s).

ORCID

Dmytro Diadin http://orcid.org/0000-0003-3421-3592

Yuliya Vystavna http://orcid.org/0000-0002-1366-0767

Notes

* Originally presented at the IAEA Symposium on Isotope Hydrology 2019, Vienna, Austria, 20–24 May 2019.

Additional information

Funding

This research was supported by International Atomic Energy Agency (IAEA) in the frames of CRP F33020 ‘Environmental isotope methods to assess water quality issues in rivers impacted by groundwater discharges’, CRP F33021 ‘Application and Development of Isotope Techniques to Evaluate Human Impacts on Water balance and Nutrient Dynamics of Large River Basins’, CRP F33024 ‘Isotope Techniques for the Evaluation of Water Sources for Domestic Supply in Urban Areas’.