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In our study, we investigate the variability of potential offshore wind power over Europe on time scales of more than 10 years. Detailed spectral analysis of potential offshore wind power capacities over the last century indicates a strong coupling to large climate patterns such as the NAO. Furthermore, combining the wind power potential at the German North Sea and the Portuguese Atlantic coast shows that the variability can be mitigated.

We simulate the deformation of Somma-Vesuvius volcano due to some overpressure sources by means of a finite element 3D code. The goal of these simulations is to investigate the influence of topography and structural heterogeneity on ground deformation. The results suggest that they are key factors governing the ground deformation. Our study clearly demonstrate that a better knowledge of deformation patterns can significantly help in the design of an efficient geodetic network.

For the documentation of time and space variations of water vapor in atmosphere during the Nawdex campaign (fall 2016), a ground network of more than 1200 continuously operation reference GNSS stations has been analyzed. This network spreads from Caribbeans to Morocco through Greenland. This study presents the retrieval of Integrated Water Vapor content from GNSS measurements and their use in the evaluation of the European Centre for Medium-Range Weather Forecasts reanalyses ERAI and ERA5.

Mineral precipitation in filters and heat exchangers can impede geothermal plant operation and cause expensive losses of efficiency. To prevent scaling a biodegradable inhibitor has been applied in a geothermal plant. Water monitoring revealed no significant chemical changes, but an adaption of the microbial community as well as a higher abundance of Bacteria after heat extraction. Laboratory experiments under anaerobic conditions showed that the inhibitor can be almost completely metabolized.

We investigate the oscillations of relative sea level through the analysis of tide gauge records collected in the Gulfs of Pozzuoli and Napoli (Southern Italy). The main goal is to provide a suitable resolution model of the sea tides including seiches, tidal bands and non-linear tides. We also target a non-conventional purpose of the tidal analysis, namely extracting from the tide gauge records the volcano-tectonic signal, the vertical ground displacement in the resurgent Campi Flegrei caldera.

The coordinates of radio telescopes, which are part of the emerging VLBI Global Observing System, were estimated in a least squares unconstrained adjustment. The higher number of observations per time with better sky coverage, which these telescopes can produce, was optimally utilized by testing different intervals for the tropospheric delay estimation. We found that a short estimation interval of 15 min for the tropospheric gradients with a 45 min interval for the zenith wet delay perform best.

Changes to a volcanic edifice and its surroundings can be caused by movements of underground magma, gas or other fluids (typically water). These deformations are usually very small in magnitude, so very sensitive instruments are the only capable of detecting them. A discrimination between deformations caused by volcanic processes in regards to those caused by external sources could help in understanding the volcano dynamics and give scientists a way to forecast volcanic eruptions.

This study focuses on the comparison of different solar radiation pressure (SRP) strategies combined with a-priori information and empirical SRP parameterization. Analysis of precise orbits as well as estimated empirical SRP parameters based on various SRP strategies shows visible differences and indicates the deficiencies of a-priori model or empirical parameterization. The orbit difference patterns presented in this study may give the view on how to improve the current SRP models.

In this study, a coupled thermo-hydro-mechanical (THM) model is implemented to simulate the processes of heat extraction, reservoir deformation, and groundwater flow in the fractured rock reservoir. The results show that the growth of the number and spacing of fracture zones can effectively decrease the pore pressure difference between injection and abstraction wells; it also increases the production temperature at the abstraction, the service life-spans, and total heat production rate.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.