University of Twente Student Theses

Login

The effect of climate change on groundwater level variation in De Wieden, The Netherlands

Leijsen, S.W. van (2022) The effect of climate change on groundwater level variation in De Wieden, The Netherlands.

[img] PDF
6MB
Abstract:Climate change predictions and subsequent consequences on the hydrological cycle have received increased attention over the past decades. While many studies explore climate change on global, regional, and local level the effect on groundwater levels is underexposed. However, groundwater plays an important role in meeting the demand for water availability, agriculture, and sustaining ecosystems making it is important to understand how climate change will affect groundwater levels. The same is the case for De Wieden, a lowland peat area in the Netherlands. The area is experiencing lateral spread towards the lower situated surrounding polders and needs a supply of external water in summer to maintain the currentsurface water and groundwater levels in the area. How climate change predictions will influence the groundwater levels in De Wieden is highly uncertain due to the small body of knowledge surrounding climate change impact on lowland peat areas. To provide insight the following objective is formulated: To determine the effect of climate change predictions on temporal and spatial groundwater level variation in De Wieden for 2050 and 2085 compared to a reference situation (1981-2010). To reach this objective first the reference groundwater level (GWL) situation is determined through simulation of the 1981 to 2010 period based on spatially interpolated precipitation and potential evaporation data from daily KNMI station measurement. To simulate groundwater levels in the study area the numerical groundwater model MIPWA v3.0 is used. The model consists of the MODFLOW groundwater model coupled with the CAPSIM unsaturated zone module to simulate important hydrological processes like infiltration, capillary rise, percolation, and irrigation. Secondly, the changes in precipitation, potential evaporation, and net precipitation for 2050 and 2085 are quantified based on the four KNMI’14 climate scenarios. The KNMI’14 scenarios provide four possible future climate scenarios for the Netherlands based on the findings of the fifth IPCC assessment report focusing on the predicted change in temperature (moderate or large increase) and air current pattern (small or large change) for 2050 and 2085. Lastly, the KNMI’14 scenarios for 2050 and 2085 are simulated using the same MIPWA v3.0 model to determine the future groundwater levels and are compared to the reference situation to determine the effect of climate change predictions. The results show that De Wieden has a shallow GWL table in the reference situation with low variation in between the years and no long-term trend. Within a year the GWL variation displays a seasonal pattern showing higher GWLs in winter and lower GWLs in summer. The KNMI’14 scenarios predict an increase in net precipitation for winter, spring, and fall but a decrease in summer for all scenarios increasing seasonality. Annually, this results in an increase in net precipitation for 2050 and 2085. Comparing the GWL for 2050 and 2085 to the reference situation showed that there is only a small change in annual GWL and inter-annual variation with no direct relation between increased net precipitation and increased annual GWL. Within a year the seasonal GWL is expected to increase in winter and spring and decrease in summer and fall increasing seasonality for all scenarios excluding scenario 2085GL. Next to that a large decrease in net precipitation is expected to decrease GWL in multiple seasons. Spatially, GWL variation is expected to increase slightly at the edges of the study area while the center is not influenced for all scenarios. This is a result of the large presence of surface water in the area with a constant surface level keeping variation next to the surface water to a minimum through lateral spread. iv Concluding, this study showed that the effect of climate change on groundwater level variation in De Wieden, a lowland peat area with an annual precipitation surplus and large presence of surface water, is limited when the surface water level can be maintained throughout the year.
Item Type:Essay (Master)
Faculty:ET: Engineering Technology
Programme:Civil Engineering and Management MSc (60026)
Link to this item:https://purl.utwente.nl/essays/89789
Export this item as:BibTeX
EndNote
HTML Citation
Reference Manager

 

Repository Staff Only: item control page