The groundwater in Bremerhaven under climate change

摘要

A 3D structural model was created for the state of Bremen based on an extensive borehole database. Parameters were assigned to the model by interpretation and interpolation of the borehole descriptions. This structural model was transferred into a flow model via the FREEWAT platform, an open-source plug-in of the free QGIS software, with connection to the MODFLOW code. This groundwater management tool is intended for long-term use. As a case study for the FREEWAT Project, possible effects of climate change on groundwater levels in the Bremerhaven area have been simulated. In addition to the calibration year 2010, scenarios with a sea-level rise and decreasing groundwater recharge were simulated for the years 2040, 2070 and 2100. In addition to seawater intrusion in the coastal area, declining groundwater levels are also a concern. Possibilities for future groundwater management already include active control of the water level of a lake and the harbor basin. With the help of a focused groundwater monitoring program based on the model results, the planned flow model can become an important forecasting tool for groundwater management within the framework of the planned continuous model management and for representing the effects of changing climatic conditions and mitigation measures.