The temporal impacts of climate condition on groundwater flow using numerical transient modelling

Sammanfattning: Compiling comprehensive understanding of all the available natural resources is an important task which should be carried out as it holds a crucial role for the next generation’s lives. In particular, groundwater is considered as one of the vital resources in providing essential drinking water. Krycklan catchment is a well-monitored catchment in Sweden that is characterized with almost 30% of the world’s forest cover and it has a range of data sets stored from 1920. A numerical model with several observational constrains is used in this study to investigate the groundwater flow circulation. The numerical model is developed with Visual MODFLOW Flex 6.1 software to investigate the temporal effects of the climate condition on the groundwater flow of the Krycklan catchment through a transient-state condition. Daily precipitation and daily evapotranspiration data along with stream data are used to represent the climatic boundary conditions. The impact of climatic condition on groundwater flow was investigated using two different metrices: groundwater level, and groundwater flow travel time reaching the stream network. The results clearly indicated the variability in groundwater level due to the impact of climatic condition in which the winter and summer months have the highest and lowest groundwater levels, respectively. In addition, the particles tracing results show that physical characteristics of the stream channel substantially influence the shallow groundwater travel time.