Groundwater recharge assessment in dry years

The climate change that has been observed in recent years has affected the water balance, including the groundwater resources recharge. The paper is an attempt to evaluate the groundwater recharge in dry years. The initial stage of the research consisted of selecting the years when meteorological and hydrological droughts occurred, with use of the standardized indices Standardized Precipitation Index (SPI) and Standardized Water Level Index (SWI). With the use of the WetSpass model for selected periods and for comparative long-term periods the volume of groundwater recharge was estimated. It was determined that the meteorological drought of 1982 led to a considerable decrease in the mean groundwater recharge to a negative level in the summer half-year in the Western Pomeranian region in Poland. On the other hand, the winter season was characterised by positive values, but they were still lower than those characteristic for the comparative long-term periods. The hydrological drought in 1992 did not have such noticeable consequences.