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Barite formation is an important factor for many use cases of the geological subsurface because it may change the rock. In this modelling study, the replacement reaction of celestite to barite is investigated. The steps that were identified to play a role are celestite dissolution followed by two-step precipitation of barite: spontaneous formation of small crystals and their subsequent growth. Explicitly including the processes improve the usability of the models for quantified prediction.

We model two kinds of demand for public charging infrastructure: As compensation for the lack of home charging points, and based on points of interest. We combine those two demands with the available parking spaces and generate distributions for possible future charging points. We use a raster-based approach on a municipality’s full grid. The model is compared with three other models in a correlation comparison in order to determine the influence of certain model assumptions and input data.

RedModRphree is an R extension package to leverage the PHREEQC engine for geochemical models, providing convenience functions to efficiently setup computations and program algorithms involving geochemical models. Version 0.3.6 ships with a novel implementation of Pourbaix (potential/pH) diagram computation which considers the full speciation of the solution at each diagram point.

Depletion of conventional hydrocarbon deposits requires implementation of the enhanced oil recovery methods, particularly based on carbon dioxide injection. The article aims at an accelerated optimisation of such methods performance by means of numerical modelling. We propose an optimisation algorithm based on the construction of a hierarchy of compositional reservoir models. We give examples of the algorithm application and discuss its performance.

Space heating makes up around 67 % of the average energy consumption in german households. While this number decreases with increasing energy standards for buildings, many heating systems still run on fossil fuels. Here, we present a method to realistically estimate the heating demand of a building, This estimated heat demand is connected to a modelled geothermal energy source, for calculating, if geothermal energy can supply the needed heat, and if more such installations influence each other.

The German site selection procedure to identify a site for the disposal of high-level radioactive waste is ongoing. The current step of the procedure includes representative preliminary safety analyses, for which the methodology is described and a first insight on the implementation is given. We aim to provide a document to boost communication and discussion with the scientific community and the public, although the implementation is at an early stage and may be subject to numerous changes.

The goal of the EMN is a harmonized, sustainable, coordinated and intelligently specialized infrastructure to support the needs expressed in the European Radiation Protection Ordinance. Such an EMN under the umbrella of EURAMET is in the founding phase and is being prepared in parallel by the EMPIR project 19NET03 supportBSS with five technical work packages. EURAMET is the Regional Metrology Organisation (RMO) of Europe. The EMN was established by signature on 16 September 2021.

In this study we evaluated subseasonal-seasonal scale forecasts of solar radiation, wind speed, temperature and relative humidity over India from 6 global models by comparing against observations. Results show that the overall quality of the forecasts are not good. However, they demonstrate enough skill suggesting that further improvement through calibration may make then useful for the renewable energy sector.

Events like mid-latitude storms with their high winds have an impact on wind energy production and forecasting of such events is crucial. This study investigates the capabilities of a global weather prediction model MPAS and looks at how key parameters like storm intensity, arrival time and duration are represented compared to measurements and traditional methods. It is found that storm intensity is represented well while model drifts negatively influence estimation of arrival time and duration.

Uranium migration in the Swiss Opalinus Clay is used as an example to quantify the influence of varying values of a stability constant in the underlying thermodynamic database within the law of mass action on the migration lengths. The difference of the stability constant of 1.33 log units lead to changed migration lengths of 5 m to 7 m. With a maximum diffusion distance of 22 m the influence of an uncertain stability constant is negligible for the host rock scale.

Flow patterns in fractal-fracture networks where the apertures scale as a power-law and a set of dominant sub-networks generated from a given fractal-fracture map by systematically removing the smaller aperture fractures is investigated. The recovery curves and TOFs of each network and its dominant sub-networks at different time steps are compared. Results show that in the case of such scaled aperture fractal-fracture systems, smaller fractures do not significantly contribute to the fluid flow.

In this paper we study how the momentum extracted by wind turbines get replenished so that the wind farm can continue to function. We use a numerical model to simulate the dynamics of a hypothetical coastal wind farm in the Arabian Sea under sea breeze conditions. Results show that vertical turbulent eddies can replenish more than half of the lost momentum, but horizontal advection also plays a role near the wind farm edges especially in sparsely packed wind farms.

The geothermal reservoir at Waiwera has been subject to active exploitation for a long time. However, the continuous production of geothermal water, to supply hotels and spas, had a negative impact on the reservoir. The aim of this work was to link the influence of the abstraction rates to the measured water level data to derive reservoir properties. For the analysis, a modified deconvolution algorithm was implemented and shown to be applicable and in accordance to results of a pumping test.

Storm Anatol was a serious winter storm of northern Europe on 3–4 December 1999. There were hurricane force winds in Denmark leading large scale power outages, closed road networks, and building damage. There was also a serious storm surge along the North Sea coasts of Denmark, Germany, and Netherlands. A detailed analysis of tide gauge data around the North Sea is carried out to study the storm surge and short period fluctuations of water level, which may be linked with large waves.

Since the problem of energy forecasting in SHPPs without storage capacity is little explored, we apply simple schemes to investigate: (a) the essential model structure and information; (b) the advantages of first using a flow forecasting model, instead of a direct energy forecasting; (c) the importance of rainfall data, as a proxy of the catchment state; (d) the training procedure and performance measure; and (e) the representation of predictive uncertainty and its practical interpretation.

Radon gas is the largest source of public exposure to naturally occurring radioactivity. Radon can also be used, as a tracer to improve indirectly the estimates of greenhouse gases important for supporting successful GHG mitigation strategies. Both climate and radiation protection research communities need improved traceable low-level atmospheric radon measurements. The EMPIR project 19ENV01 traceRadon started to provide the necessary measurement infrastructure and transfer standards.

Tritium concentration analyses were performed on groundwater samples collected in wells in the south part of Treviso city, to correlated the presence of tritium with the young age of the water recharge. The results show strong differences in recharge by recent rainwater which reflect the variation in permeability of the sediments. The aquifer analyzed was vulnerable to prolonged drought periods which could produce a worsening of water quality, consequently limiting water availability.

Underground laboratories (ULs) are of great interest and must be adequately tested, a.o. for their natural radioactivity (NR). It is essential from the point of view of safety and radiological protection of people and the success of underground experiments. The article contains a summary of six ULs operating in the Baltic Sea region regarding their NR. The study was performed using specialized measurement methods. The lowest level of NR characterizes salt deposit in Conceptual Lab (Cuprum).

Seismic imaging while drilling (SWD) technology offers possibilities of imaging ahead of the drill-bit, which is valuable information for optimizing drilling efficiency. An SWD field test was carried out in August 2020 at an exploration drilling test site in Örebro, Sweden, with the aim to determine if the signals from hammer drilling can be used for seismic imaging around the drill-bit. A comparison with the seismic data generated with a conventional seismic source shows reasonable agreement.

Sardinia Region promoted a plan to protect the population from exposure to radon gas. Communication activities are ancillary to develop the whole monitoring and risk identification, a work in collaboration among professionals, a dialogue with policy-makers and the community in general, to develop awareness and prevention. Strengths, weaknesses and lessons learned are shown.

There is a growing need in health and climate research for high-quality radon observations. A variety of radon monitors, with different uncertainties, operate across global networks. Better compatibility between the measurements is required. Here we describe a novel, portable two-filter radon monitor with a calibration traceable to the International System of Units, and demonstrate the transfer of a traceable calibration from this instrument to a separate monitor under field conditions.

Indoor/outdoor air exchange on indoor radon concentration was investigated. We evaluated the effect of air exchange on radon concentration in a scale model room. Air introduction was more effective than air extraction to reduce indoor radon, especially at higher flow rates. The presence of plasterboard shields on the inner walls of the room improved the results. This suggests that the combined use of inner coatings and outdoor air introduction are a good strategy for radon mitigation.