Climate change effects on groundwater resources: a new assessment method through climate indices and effective precipitation in Beliş district, Western Carpathians

Abstract

Climate change is a topic of enormous interest due to its direct impact and long-term consequences. The ongoing climate warming is triggering global impacts and it is likely to alter natural systems at the local scale, too. The observed climate variability in the Romanian Carpathians has been tackled by several researchers and the negative impact of climate change on groundwater vulnerability has also been assessed. A temporal analysis of four climate indices (De Martonne, UNEP Index, Johansson Continentality Index and Pinna Combinative Index) and crop evapotranspiration over the past 50 years was performed to understand the climate trends in the Beliş district, to estimate the effective precipitation in the area and to assess the effects of climate change on groundwater resources. Land cover data were extracted from satellite images and crop evapotranspiration data were evaluated based on field co-efficients. An examination of the climate index trends and change points was carried out using the Rodionov test. In the study area, the climate indices indicated very humid and marine climate conditions. At the same time, it was noticed that the crop evapotranspiration values increased from 1961 to 2013 and the annual effective precipitation ranged between 200–300 mm. In order to understand the impacts of climate change on groundwater resources, an innovative method was proposed using an inference matrix that combines the climate indices and effective precipitation. Based on this method, the climate indices and effective precipitation for four decades indicated a low impact of climate change on groundwater resources in the Beliş district.