DOI: 10.5880/gfz.4.5.2024.001
title: Transient 3D groundwater and temperature model of the North German Basin below the State of Brandenburg (1953-2014)

description: The dataset is the basis for describing a 60-year-long evolution of groundwater dynamics and thermal field in the North German Basin beneath the Federal State of Brandenburg (NE Germany), covering the period between 1953 and 2014 with monthly increments. It was produced by one-way coupling of a near-surface distributed hydrologic model to a 3D basin-scale thermohydraulic groundwater model with the goal of investigating feedbacks between climate-driven forcing (in terms of time- and space-varying recharge and temperature), basin-scale geology, and topographic gradients. Modeled pressure and temperature distributions are validated against published groundwater level and temperature time series from observation wells. Our results indicate the spatio-temporal extent of the groundwater system subjected to nonlinear interactions between local geological variability and climate conditions. 
 
The dataset comprises of input files and scripts required to run the groundwater model in GOLEM and output files from the transient thermo-hydraulic simulations in EXODUS format. The input and output data is organized as separate archived folders (*.gz format).
description: Hydrological fluxes are simulated via mesoscale Hydrological Model (mHM) (Samaniego et al., 2010), a spatially distributed hydrologic modeling tool. We make use of the results from a Germany-wide realization of mHM to derive time and space varying water fluxes, which we translate into boundary conditions at the top of our groundwater model. 
 
All groundwater simulations were conducted with GOLEM, a Finite Element Method (FEM) modelling platform for thermal-hydraulic-mechanical and non-reactive chemical processes in fully-saturated porous media (Cacace and Jacquey, 2017). Steady-state conditions were derived by solving separately for the hydraulic and the thermal cases. These uncoupled steady-state simulations have been used as initial conditions to run a coupled pseudo-transient simulation, the results of which have been later imposed to initialize the pore pressure and the temperature in the final transient simulation.
description: The dataset comprises of output fluxes from the hydrological model, input files and scripts required to run the groundwater model, output files from the transient thermo-hydraulic simulations, references to validation data, and workflows for data pre-conditioning and post-processing. 
 
The 3D structural model built for groundwater modeling covers an area of 28800 km2, extends down to 6000 m below sea level, and contains 12 stratigraphic units from pre-Permian to Quaternary. It was built using structural surfaces from an earlier basin-scale structural model of Brandenburg (Noack et al., 2013). The model captures large-scale geological features controlling the regional groundwater flow, including salt structures, permeable glacial valleys, and aquitard discontinuities. The simulated finite element mesh has a resolution of 1 km x 1 km. It is divided into 54 computational layers and consists of 1.9 million nodes, giving a total of 3 million degrees of freedom.