Groundwater recharge modelling approach to identify climate change impacts using groundwater levels from Tärnsjö.
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Groundwater is a sensitive component affected by climate change. Modelling the dynamics of groundwater levels is inherently difficult particularly as the response to climate change. Given this complexity, most of the current studies using long term groundwater time series were conducted by statistical analysis or using over simplified assumptions to represent the physical processes in hydrological system. With the objective of providing an improved physically based groundwater modelling approach to support climate change impact assessment, a dataset of long term time series of groundwater levels from two different soil types (sand and till) were selected from the Tärnsjö area located in southeast of Sweden. The CoupModel was chosen to perform the simulation since it offers a physically based representation on groundwater recharge processes. A two-step strategy for calibration with first short-term calibration followed by long-term testing was adopted. Simulated groundwater levels followed the general patterns of measured groundwater level dynamics; however, auto-correlations and periodicities were observed in residuals for all sites of which two sandy soil sites with deeper groundwater tables maintained strong auto-correlations in long time lags and an extra 15.4-year periodicity. The long memory of the system rendered it more susceptible to climate change. Uncertainty arises if different initial condition had been applied in short term period calibration.
Place, publisher, year, edition, pages
, TRITA-LWR Degree Project, ISSN 1651-064X ; 2014:19
Groundwater levels; Climate Change; Physically-based model; Long-term groundwater level time series
IdentifiersURN: urn:nbn:se:kth:diva-171774OAI: oai:DiVA.org:kth-171774DiVA: diva2:844473
Degree of Master - Environmental Engineering and Sustainable Infrastructure