bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving estimation of spatial precipitation in mountain regions
Authors: Shotton Keith , Lewis Liz , Pritchard David , Rutter Nick , Blenkinsop Stephen
Published: March 2024

Around 22% of the global population depend on mountain runoff for their water supply. Due to its importance for future water resources, as well as flood and drought planning, an improved understanding of spatial precipitation patterns in mountain regions is needed. Precipitation gauge networks are sparse and traditional methods of interpolation yield inadequate precipitation fields for poorly gauged mountain catchments.This research project builds on a new method, Random Mixing, to generate multiple random spatial daily precipitation fields, conditioned on gauge observations. The Random Mixing algorithm has so far been tested on larger, densely gauged catchments. This project adapts the approach for a sparsely gauged, small 9.1 km2 mountain catchment, Marmot Creek Research Basin in Alberta, Canada, where elevations range between 1600 m and 2825 m above sea level (a.s.l.). Quality-controlled total precipitation (i.e., rainfall and snowfall) gauge observations, for an 11-year period, from three weather stations around the catchment have been used to condition the random spatial fields.Three modifications have been made to the Random Mixing method: improving spatial covariance, introducing elevation dependence and evaluating seasonal effects. Leave-one-out cross-validation is used, comparing spatial fields from the new method with other spatial interpolation techniques, including Inverse Distance Weighting and Kriging with External Drift. Results are promising: even with very few gauges, improving the way that spatial covariance relationships between gauge locations are represented in the model has enhanced the quality of the spatial fields.To optimise selection of the most plausible fields, ensemble hydrological simulations are run, using a modified version of the HBV spatially-distributed conceptual model, and the physically-based Cold Regions Hydrological Model (CRHM), with spatial precipitation fields generated on a 50 m2 regular model grid. Optimisation involves the use of metrics, primarily Nash-Sutcliffe Efficiency (NSE) and bias, to identify the fields that result in the best match between observed and simulated streamflows. Outputs from HBV and CRHM ensemble simulations are compared to evaluate the impact of model structure on catchment response and spatial precipitation field optimisation.
The effect of nano fertilizers on wheat vegetative characters
Authors: Buacharoen Thanawan , Guo Yafei , Valsami - Jones Eugenia , Ullah Sami
Published: March 2024

The effect of nano fertilizers on Wheat vegetative charactersThanawan Buacharoen1, Yafei Guo1, Eugenia Valsami-Jones1*, and Sami Ullah1*Authors to whom correspondence should be addressed.1School of Geography, Earth and Environmental Science, College of Life and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UKWheat is the primary staple cereal in the world. It was the highest cultivation in 2018. According to the British Survey of Fertilizer Practice, total nitrogen use in Great Britain was reduced between 2021 and 2022. At the same time, the total phosphate did not change. Meanwhile, the usage of the total potash has increased compared to last year.  Conventional fertilizer, which consists of nitrogen, phosphorous, and potassium nutrients, will release Greenhouse gas emissions. The other option to solve this problem is the nano fertilizer. Plants can easily absorb a tiny particle of nano fertilizer, reducing greenhouse gas emissions into the air. Therefore, this study focused on nano fertilizers' effect on plant growth. The first set of 30-day-old wheat plants was treated with amorphous calcium phosphate (nano - ACP), a potassium-bearing variant of the ACP (nano ACP - NPK) and a urea and potassium-bearing variant of the ACP (nano - UNPK). Moreover, three conventional fertilizers, which have the same nutrient quantity as same as nano fertilizers, were applied to the second set of plants to be a positive control. On the other hand, blank treatment was used to be a negative control. After harvesting the wheat plants, the shoot length and fresh weight were measured. Also, the ammonium concentration in the soil was examined with the colorimetric method. Maximum root weight was found in the wheat treated with nano–ACP (Average± SD. = 0.39±0.20). The nano ACP - NPK gave the highest value of shoot weight (Average ± SD. = 0.9 ± 0.10), number of seeds (84 seeds) and shoot length (Average ±SD.= 63.33 ± 4.29). However, the maximum ammonium concentration was found in the soil treated with nano ACP. All treatments' seed weight and shoot length differ at the P – value of less than 0.5. Our finding suggests that the nano fertilizers had enhanced vegetative characteristics compared with the conventional fertilizers.Key word; amorphous calcium phosphate (nano - ACP), potassium-bearing variant of the ACP (nano ACP - NPK) and urea and potassium-bearing variant of the ACP (nano - UNPK)        
Assessment of Climate Effects in the Three Gorges Reservoir Based on Multi-source Fusion Data CLDAS
Authors: Wang Qiuling , Chen Xianyan , Li Wei
Published: March 2024

In order to alleviate the problem of water scarcity, adapt to and mitigate the negative impact of climate change on water resources, large-scale infrastructure projects have been built worldwide. In addition to bringing huge social benefits, reservoirs may also affect meteorological conditions near the surface and mesoscale or weather scale processes. A high-quality meteorological dataset is an important foundation for understanding climate change. Considering the complexity of the underlying surface in the Three Gorges Reservoir region, this study uses CLDAS multi-source fusion grid meteorological data to study the characteristics of changes in the Three Gorges Reservoir before and after water storage. Select four elements: temperature, precipitation, wind speed, and relative humidity, and analyze the climate effects before and after the Three Gorges Reservoir from different time scales such as year, season, and day. Based on the analysis of CLDAS multi-source fusion data, it is shown that for the average temperature, after the water storage, except for the areas along the southern side of the Yangtze River where the temperature is lower than before the water storage, most other areas are higher. On an annual scale, there is not much difference in average temperature before and after water storage. The average temperature effect in the Three Gorges region after water storage varies at different time periods. During the subsidence period and high water level period, it shows an overall warming effect, with an average temperature increase of 0.1 ℃ and 0.3 ℃, respectively. However, during the flood season and water storage period, it shows a cooling effect, with an average temperature decrease of 0.2 ℃ and 0.9 ℃, respectively. The cooling effect is more pronounced during the water storage period. After water storage, it shows an increase in temperature during the day and a decrease in temperature at night. For annual precipitation, except for some areas in the east, northwest, and central regions where precipitation has decreased, most of the remaining areas of the Three Gorges generally have more precipitation than before the water storage. At the annual scale and different time periods, the precipitation in the Three Gorges area is higher after the water storage than before, and on the annual scale, the precipitation after the water storage increases by 8.8% compared to before the water storage; During the subsidence period, flood season, storage period, and high water level period, the precipitation after storage increased by 10.2%, 1.3%, 21.7%, and 32.2% respectively compared to before storage. The precipitation during the high water level period after storage changed the most, while the precipitation during the flood season changed the least.
Surface air temperature response to strong volcanic clusters in the Last Glacial Maximum
Authors: Dutta Deepashree , Hopcroft Peter , Aubry Thomas , Muschitiello Francesco
Published: March 2024

Stratospheric aerosol injection from volcanic eruptions results in a complex set of responses driving climate effects across various time and spatial scales. However, the physical mechanisms through which volcanic forcing causes long-term global and regional cooling remain insufficiently examined. In particular, the climate feedbacks and responses to a cluster of strong volcanic eruptions that occurred pre-Holocene are still poorly quantified. We examine the cooling potential of volcanic clusters and assess the short- and long-term memory of regional and global climatic variability using a suite of idealised volcanic forcing experiments with the Hadley Centre Coupled Model, version 3. We compare the responses to Northern Hemisphere high and low latitude volcanic clusters and the impact of different boundary conditions. We find a largely similar surface air temperature response to low and high latitude volcanic clusters. Individual volcanic eruptions lead to a global mean surface air temperature cooling of approximately 0.5°-1.5°C, and this cooling appears to increase after successive eruptions. We also investigate changes in the coupling between northward heat transport, Arctic sea ice, and the Atlantic Meridional Overturning Circulation caused by the volcanic forcing.
Accurate Representation of Dual-Polarized Radar Parameters with Data Assimilation
Authors: Lee Ji-Won , Min Ki-Hong , Lee GyuWon
Published: March 2024

To enhance the accuracy of heavy rainfall prediction, the assimilation of radar data (DA) is crucial. Single-polarized radar variables, such as reflectivity and Doppler velocity, offer insights into raindrop quantity and speed. Dual-polarization (dual-pol) radar variables, including differential reflectivity (ZDR), specific differential phase (KDP), and co-polar correlation coefficient (ρhv), provide additional details about hydrometeor phase, size, and liquid water content. Assimilating dual-pol radar variables into a Numerical Weather Prediction (NWP) model can enhance the accuracy of predicting both large-scale and rapidly developing mesoscale precipitation events. Therefore, the development and application of an accurate radar observation operator for DA, considering the microphysical information of an NWP model with dual-pol radar data, is necessary.
In this study, we developed a dual-pol radar operator based on microphysical variables such as the mixing ratio and total number concentration of hydrometeors. The enhanced method can accurately replicate the characteristics of dual-pol radar variables in the melting layer, improve the underestimation of hydrometeors mixing ratio for liquid and ice particles. Enhancing the estimation of hydrometeor increments further refines the prediction of mesoscale precipitation effects. This study aims to demonstrate improvements in microphysical processes and enhanced accuracy in rainfall predictions through dual-pol radar DA.
※ This work was supported by the National Research Foundation (NRF) grant funded by the Korea government (MSIT)(No. 2021R1A4A1032646, 2022R1A6A3A13073165) and the Korea Meteorological Administration Research and Development Program under Grant RS-2023-00237740.
Nutrient removal in constructed wetlands: Especial emphasis on type of plantation method
Authors: Jain Mahak , Sharma Balram , Pilla Sai Kiran , Ghosal Partha Sarathi , Gupta Ashok Kumar
Published: March 2024

Constructed wetlands (CW) have emerged as sustainable and eco-friendly solutions for mitigating the impact of nutrient pollution in water bodies. Nutrient pollution, primarily caused by excess nitrogen and phosphorus, poses significant threats to aquatic ecosystems, leading to issues such as algal blooms, oxygen depletion, and impaired water quality. In response to these challenges, constructed wetlands have gained prominence as innovative systems capable of efficiently removing nutrients from wastewater and stormwater. These engineered ecosystems mimic the natural processes of wetlands to effectively treat wastewater. Among the key factors influencing the efficiency of nutrient removal, the choice of plantation method in CW stands out as a crucial aspect that demands closer scrutiny. As such, understanding the impact of different plantation methods on nutrient removal becomes paramount for optimizing the performance of constructed wetlands. This study focuses on elucidating the role of diverse vegetation strategies in enhancing the performance of these systems, with particular emphasis on nutrient uptake and transformation processes. Through a comprehensive review of existing literature, this research aims to identify and analyze the impact of various plantation techniques on nutrient removal efficiency. Factors such as plant species selection, plantation type i.e., single plant in a system (monoculture) or multiple vegetation in the system (polyculture) are examined to ascertain their influence on nitrogen and phosphorus removal rates. Polyculture improved TN and TP removal in horizontal subsurface CW by around 5%. However, a very high increment in treatment efficiency of both TN and TP was observed for vertical subsurface CW being more than 20%. Polyculture provided synergistic effect of various plant and microbial species for higher removal of nutrients from wastewater. Ultimately, the research aims to delineate the effect of plantation on performance of different CW in terms of mitigation of nutrient pollution in wastewater.
An evaluation of the use of regional climate model data applied to extreme precipitation in the Meuse basin
Authors: van Voorst Leon , van den Brink Henk , Couasnon Anais
Published: March 2024

Understanding of hydrological and meteorological extremes is essential for flood risk management and flood protection. A primary focus in these professions is adequate estimation of extreme events that correspond to large return periods. Hydrological and meteorological observations only go back several decades, complicating frequency analysis of these large extremes. Capturing the tail behaviour of extremes is particularly challenging with such short records, resulting in high uncertainty of large precipitation and discharge extreme estimates.This study proposes an alternative strategy for hydrological and meteorological frequency analysis. Long timeseries obtained from regional climate models are used to replace short observational datasets, leading to a substantial reduction of the statistical uncertainty of meteorological and hydrological extreme estimates. The approach was tested in the Meuse basin as part of the EMFloodresilience project, evaluating meteorological extremes from 16 synthetic ensembles of 65 years from the RACMO regional climate model (forced by the EC-EARTH global climate model). Hydrological extremes are analysed in a subsequent study from Rijkswaterstaat and Deltares, by forcing the wflow discharge model with the RACMO climate model dataset.The study results reveal that bias-corrected model data is climatologically comparable to observational averages and extremes, exhibiting similar GEV location and scale parameters. Revealing a previously unexamined range of extremes, the model data offers a more plausible method to estimate the tails of annual extremes and likely provides a better estimate of the corresponding GEV shape parameter. Spatially, the model-derived parameter shows greater consistency across different sub-catchments of the Meuse basin compared to observations, suggesting a more robust insight in the tail behaviour of extremes. Additionally, a distinct separation between GEV distributions of summer and winter events is observed, indicating a transition in magnitude dominance from winter to summer maxima and possibly the presence of a double population. The existence of such a double population is difficult to obtain from observations, but can have an enormous impact on the return values of summer extremes. This emphasizes the need for further research on this area for adequate flood management.
High frequency isotopic composition measurements to classify cloud induced turbulent patterns above the amazon rain forest
Authors: Moonen Robbert , Adnew Getachew , Hartogensis Oscar , Vilà-Guerau de Arellano Jordi , Bonell Fontas David , Röckmann Thomas
Published: March 2024

During the 2022 CloudRoots-Amazonia field campaign high-frequency measurements of state variables and atmospheric composition were taken at the Amazon Tall Tower Observatory (ATTO) in Brazil. Specifically, we measured wind fields, radiation, H2O and CO2 mole fractions, and H2O and CO2 isotopic compositions at 4Hz or faster at 57m height. A main objective was to use these high-frequency measurements to investigate how the coherent canopy-atmosphere turbulent structures are influenced by the non-stationary passage of clouds. Novel in our investigation is the use of quadrant analysis in combination with high frequency isotopic composition measurements, as well as our approach to finding lag between cloud passages and turbulent variables.Using quadrant analysis to distinguish sweeping and ejection motions, we find that the passage of clouds influences the transport of scalars and energy. Preceding the passage of well-developed cumulus clouds, we see that the gust front forcefully ejects this subcanopy air into the atmospheric mixed layer. It seems that this is an effective upward transport mechanism for CO2 and other scalars emitted by the soil, plant roots, and understory. The understory separation was based on the qCO2’ > 0, qH2O’ > 0 quadrant. Keeling plots of this quadrant, made using the dD isotope of H2O, indicate strong midday depletion of understory water vapour (-20 ‰). This effect can only be explained by a major downwards moisture flux from the atmosphere into the soils through the process of condensation, even - or especially – when the air temperatures are highest. Finally, we show what the responses of the major fluxes (H, LE, FCO2) and their respective isotopologues are to the passage of clouds, including their lag times. Our study contributes to an improved quantification and understanding of the canopy-atmosphere fluxes influenced by the perpetual presence of clouds.
Reducing methane emissions from documented abandoned and orphaned oil and gas wells in Canada and the United States 
Authors: Boutot Jade , Kang Mary
Published: March 2024

Millions of oil and gas wells are abandoned and orphaned around the world. Due to funding shortfalls, many abandoned and orphaned wells remain unplugged and are negatively impacting the environment and contributing to greenhouse gas emissions, such as methane. To reduce emissions and environmental impacts, the wells are required to be plugged, but the well sites can be repurposed for wind and solar energy and/or the wells itself can be redeveloped for geothermal energy production. To quantify methane emissions and identify opportunities for repurposing abandoned and orphaned wells and well sites for renewable energy development, we analyze public oil and gas well data from governmental agencies of documented abandoned and orphaned wells in Canada and the United States. We estimate the total number of abandoned and orphaned wells in Canada and the United States to be 3,500,602, of which 4% are orphaned and in need of government funding. We estimate plugging costs for orphaned wells in the United States to exceed federal funding by 30%-80%. For abandoned and orphaned wells, we quantify methane emissions at the national and state/provincial/territorial level and potential emission reductions achieved through plugging. Furthermore, to evaluate mitigation and redevelopment opportunities, we analyze geographic locations of abandoned and orphaned wells with national maps of renewable energy potential (geothermal, wind, and solar) and land cover/land use in Canada and the United States. Mitigating oil and gas wells can help fulfill national energy transition goals and emission reduction targets, while providing an additional funding stream to manage the millions of abandoned and orphaned wells around the world. 
PRISMA Hyperspectral images for Tree Cover classification with Machine Learning algorithms a comparison with Sentinel-2 
Authors: Caputi Eros , Delogu Gabriele , Patriarca Alessio , Perretta Miriam , Boccia Lorenzo , Ripa Maria Nicolina
Published: March 2024

Remote sensing (RS) images are fundamental for earth observation and for the analysis of land cover and land cover change providing useful information for agroforestry planning and management. Multispectral data are the most common, such as those provided by the Sentinel-2 satellite, which inherits the legacy of the Landsat satellite. More recently, images from the Italian PRISMA satellite, which provides hyperspectral images, have opened new perspectives in land analysis due to an improved spectral resolution. The study area is situated in the Lazio region (Italy), it was selected for the presence of homogeneous and extensive wooded surfaces of large forest areas and orchards.  In this study an evaluation and a comparison of the results of Tree Cover classes classification obtained using images from different sources has been carried out. The PRISMA and Sentinel 2 images have been downloaded and preprocessed for comparison. The classification based on advanced machine learning techniques was carried out and the results have been compared by evaluating the achieved accuracy metrics with the different images. The study showed that the advantages represented by the higher spectral resolution are at least partially offset by the lower spatial resolution of PRISMA images. Due to the short time since the beginning of the PRISMA mission and the limited availability of images, the study represents one of the early examples of applying the potential of the PRISMA satellite.
Development of a calculation method for viscoelastic relaxation incorporating nonlinear rheology in a self-gravitating spherical Earth model
Authors: Nakakoji Kazuma , Tanaka Yoshiyuki , Klemann Volker , Martinec Zdeněk
Published: March 2024

Space geodetic techniques such as GNSS have been used to observe co- and post-seismic crustal deformation in subduction zones with high spatio-temporal resolution. However, it is difficult to observe such crustal deformations in oceanic regions. Satellite gravimetry, on the other hand, can detect co- and post-seismic mass changes both over land and ocean. However, the spatio-temporal resolution of these satellites is insufficient to distinguish co- and post-seismic effects. The planned MAGIC mission aims to achieve a 3-day, 100 km resolution, enabling their separation. This advancement is expected to provide a more precise understanding of the mechanisms of post-seismic deformations following major earthquakes. Geodetic observations have so far shown that there are three mechanisms of post-seismic deformations: afterslip, poroelastic rebound, and viscoelastic relaxation. The last one, viscoelastic relaxation has not been considered to contribute to short-term deformations unlike other two mechanisms. However, seafloor geodetic observations after the 2011 Tohoku earthquake captured the characteristic deformation even one year after the earthquake, which cannot be interpreted without a contribution of viscoelastic relaxation. Geophysical models that reproduce such viscoelastic relaxation have been proposed considering surface topography and 3D viscoelastic and density structure including a subducting oceanic slab. However, there are only a few models incorporating a nonlinear rheology to calculate post-seismic gravity changes. In the nonlinear case, the effective viscosity changes in space and time with stress evolution. In particular, co-seismic high stress changes lead to low effective viscosity, which promotes short-term viscoelastic relaxation after an earthquake. Hence, it is essential to discuss the extent to which this mechanism can be constrained when satellite gravity data with high spatio-temporal resolution become available by MAGIC. Previous physical models to calculate post-seismic deformation have often treated the self-gravitation effects only approximately or ignored it. To represent the effects naturally, we have developed a spectral finite-element method based on a spherical earth model with a 3D viscosity distribution for a linear rheology.　In this study, we extend this method to a nonlinear rheology. This method computes the deformation in the time domain. Therefore, one can easily obtain the deformation for the nonlinear case by evaluating effective viscosity at each time step without major changes in the algorithm for the linear case. In the presentation, the spectral finite element method will be introduced, and numerical results will be shown, including viscosity distributions corresponding to co-seismic stress changes and their time evolution, and gravity signals reflecting a nonlinear rheology.
Using received laser signal intensity to measure snow and ice surface properties automatically 
Authors: Prokop Alexander , Tolle Florian , Friedt Jean-Michelle , Bernard Eric
Published: March 2024

In the context of climate warming it is a common scientific goal to study and monitor surface and volume changes of glaciers and melting dynamics of its snow and ice. Therefore several measurement techniques exist to track permanently ice melting e.g. DGPS stations on glaciers, Smart stake, and snow and ice depth measurements via e.g. ultrasonic depth sensors to create time series of snow and ice loss or gain. None of the existing methods measure if actually liquid water is present and melting occurs, this is later concluded by interpretation of the geometric data. The capability of the laser sensor to do so via the reflectance value, in fact the received signal intensity, we consider as a big advantage and worth investigating further as a direct measure of snow or ice melt that helps not only to analyze glacier dynamics but is also important e.g. for providing reliable ground truth data for satellite remote sensing. When melting of snow and ice occurs, water changes the reflectance properties as due to absorption of the laser in water, only a portion of the laser is reflected. This allows determining if liquid water is present at the surface measured. We present the data collected in the last 2 melting seasons of the Austre Lovénbreen glacier near Ny Alesund, Svalbard. We show how we classify wet snow and wet ice hours with confidence and are able to compute melting rates. The single point measurement is put into context to area wide LiDAR measurements and melting dynamics of the glacier are analyzed. The data was verified against visual inspections from automatic cameras, data from an automatic weather station both located in the glacier catchment and ice melt was measured in close proximity with a SmartStake station.
DeepSoil2100 and SWÆDIE (the Soil WArming Experiment Data Integration Effort)
Authors: Beem Miller Jeffrey , Torn Margaret , Reich Peter , Riley William , Schmidt Michael
Published: March 2024

How do soils respond to warming temperatures? The importance of soils in the global carbon cycle and as hotspots of biogeochemical processes in terrestrial ecosystems underscores the imperative of understanding this response. Soil warming experiments have proved to be a key tool for probing the mechanisms underlying warming responses. However, climate, mineralogy, flora, fauna, and methodology specific to each experimental site hamper efforts to generalize and upscale these findings. The DeepSoil 2100 project was initiated to synthesize data from soil warming experiments worldwide through the creation of a harmonized database (SWÆDIE, the Soil WArming Experiment Data Integration Effort). SWÆDIE emphasizes experiments in which soils have been warmed ≥ 1 m, and will enable us to explore depth-dependence and coupling between above and belowground processes, assess feedbacks and interactions between C stocks, nutrients, and soil moisture, compare short versus long-term warming responses, and identify global patterns.Collaborative projects such as SWÆDIE require establishing clear guideline for data sharing and attribution of credit, for which we are building on the models provided by Ameriflux and NutNet. We have also drawn from other soil carbon-focused synthesis efforts such as ISRaD, SoDaH, and ISCN to construct a transparent and flexible data model with a user-friendly data access interface. Data are organized hierarchically, with a static site-level table and dynamic subordinate data tables, e.g., time series of fluxes, moisture, and temperature, resolved by depth. We maintain raw data files that are harmonized in a scripted data entry pipeline with the aid of separate metadata files describing variable names and units. Such an approach facilitates new data ingestion while also ensuring reproducibility and transparency.We will present the results from the initial site characterization, including quantification of heating efficacy and the relationship to changes in soil moisture with depth and across sites. This initial site characterization will also allow us to compare data coverage and define the scope of soil, climatic, and vegetation gradients across the database. On the basis of this comparison, we will present plans for coordinated future sampling. Finally, we will present initial work on establishing improved metrics for model benchmarking, i.e., which modellable response variables are both sensitive and robust when measured across sites?
An interactive climate atlas for northern Europe
Authors: Parding Kajsa , Dobler Andreas , Benestad Rasmus , Lutz Julia , Mezghani Abdelkader , Dybdal Anita Verpe
Published: March 2024

We present an interactive climate atlas providing visualisations of future regional climate projections of temperature and precipitation in northern Europe from multiple sources. It is based on results of both empirical-statistical and dynamical downscaling of multi-model ensembles from CMIP5 and CMIP6 including several emission scenarios. Displayed alongside each other, the projected climate change estimated from different model ensembles can be compared and contrasted. The comparison can be useful to evaluate the robustness of the climate change information and the influence of methodological choices such as the downscaling method and the selection of global climate models, and to explore how the level of greenhouse gas emissions may affect the future climate. The application is developed by researchers at the Norwegian Meteorological Institute and is freely available at the website futureclimate.met.no/dse4KSS.
A contribution towards the understanding of the “bradyseism” phenomenon at the Campi Flegrei volcanic area (Southern Italy)
Authors: Milano Girolamo , Bellucci Sessa Eliana
Published: March 2024

Following the recent unrest phase occurred at Campi Flegrei Caldera in the last years, the population’s demand for information on the “bradyseism” phenomenon has significantly increased. The bradyseism consists in a slow subsidence or uplift ground movement that always has characterized the dynamics of the Campi Flegrei volcanic area. Generally, seismic activity accompanied ground uplifts whereas no seismic activity occurred during ground subsidence. In order to contribute towards the understanding of this particular phenomenon for the population residing in the Campi Flegrei area, we created an exhibition panel, which shows the general trend of the bradyseism since the year 34 A.D. up to modern times. The central panel shows a graph created by merging information from historical sources, geodetic levelling and GNSS data published in recent papers. The altimetric reference “0” of this panel is that of the average see level referred to the year 1900. To make the exhibition panel more incisive, we insert in the graph copies of vintage prints and postcards of the ruins of a monument located in proximity of the city of Pozzuoli’s harbor: The Macellum, best known as Serapeum. The peculiarity of this ancient Roman market is the presence, at various heights on the three still erected columns, of lithodome holes that are an indication of the sea level in the past. The images of the vintage prints (since about 1730) and of the postcards (since about 1850), well show the Serapeum in the phase of subsidence or ground uplift being its floor flooded with water (below sea level) or dry (above sea level). The vintage prints and postcards, inserted in correspondence of the date when realized, well support the trend in the graph. The exhibition panel was presented at “Notte dei Ricercatori” event (Napoli 29 September 2023) and in occasion of the “Futuro Remoto” event (Napoli 22-27 November 2023), receiving notable public success for the accompanying images that well helped in understanding the bradyseism phenomena.
Modelling coupled hydro-mechanical processes of gas flow in the Opalinus Clay
Authors: Nuus Matthijs , Rinaldi Antonio Pio , Cuss Robert , Sentis Manuel , Gisiger Jocelyn , Graupner Bastian , Magri Fabiano , Bernier Frederic , Jaeggi David
Published: March 2024

Deep geological repositories rely on a natural geological barrier with a low permeability to ensure radioactive waste containment and prevent radionuclide transport into the biosphere. For the Swiss repository concept, the Opalinus Clay formation is considered as the natural geological barrier. After high-level radioactive waste are disposed of in a repository within the host-rock, corrosion of metal containers in anaerobic conditions can result in the release of hydrogen. Due to the low-permeability of the host-rock, elevated gas pressures are expected. If the gas pressure exceeds the minimum principal stress, fracturing of the rock could occur. It is therefore important to assess the possible impacts of this process on the integrity of the repository such as a possible increase of the permeability of the host formation.Production of hydrogen is anticipated to span more than 100,000 years, and understanding how gas transport occurs in a low-permeable host-rock is therefore an important aspect for the long-term safety of the repository. Gas transport can generally be subdivided in four different mechanisms: (1) advective-diffusive flow, (2) visco-capillary two-phase flow, (3) dilatancy-controlled gas flow and (4) gas transport along macroscopic tensile fractures. Gas flow rate and the microstructure of the host rock largely control the dominating gas transport mechanism, but the exact variables determining the process are poorly quantified.The GT (Gas Transport) experiment at Mont Terri was designed to study the pressure and deformation effects after injecting gas into the Opalinus Clay. Helium was injected with increasing pressure increments until a gas breakthrough was observed. The borehole into which the helium was injected was surrounded by eight observation boreholes providing deformation and pore pressure observations.The results of the experiment have been used to create a coupled hydro-mechanical model using TOUGH-FLAC, which couples the multiphase flow and heat transport simulator TOUGH3 with the geomechanical simulator FLAC3D. The model uses the helium injection rates as input and computes the resulting pressure and deformation responses. By running models with different transport mechanisms (e.g. two-phase only, both two-phase and dilatancy, allowing fracture formation) and by comparing the pressure and deformation results with the observations, insight is gained into the dominant transport mechanisms in the Opalinus Clay. Preliminary results reveal a slow build-up of strain and a relatively small pressure drop after gas injection begins, suggesting that dilatancy-controlled gas flow occurred.
Assessing the geometry and topology of a fault network along the Northern North Sea rift margin: insights from broadband 3D seismic reflection data
Authors: Osagiede Edoseghe Edwin , Nixon Casey , Gawthorpe Rob , Rotevatn Atle , Fossen Haakon , Jackson Christopher A-L. , Tillmans Fabian
Published: March 2024

Recent advances in seismic reflection acquisition and processing technologies have led to a general improvement in the resolution of seismic reflection data, allowing for better imaging of subsurface structures, particularly fault networks. Leveraging high-resolution, broadband 3D seismic reflection data from the northern North Sea, we, for the first time, investigate how the geometrical and topological properties of the Late Jurassic normal fault network vary spatially along the rift margins. We also discuss the factors that may have influenced the spatial variability of the rift fault network properties. Our results reveal that normal faults closer to the North Viking Graben exhibit dominant N-S and NE-SW strikes that are sub-parallel to the graben axis and associated step-over zone, whereas those farther from the graben, exhibit an additional NW-SE strike, resulting in a complex fault network. We identify two broad topological domains within the fault network: 1) dominated by isolated (I-) nodes, partially connected (I-C) branches, low fault density, and connectivity, and 2) dominated by abutting (Y-) nodes, fully connected (C-C) branches, moderate to high fault density and connectivity. These topological domains correlate with previous sub-division of the rift margin in the northern North Sea into platform and sub-platform structural domains, respectively. There is also a positive correlation between the spatial variability of the fault orientations, density, and connectivity, highlighting the relationship between normal fault network geometry and topology. We conclude that variation in the amount of relative strain, the presence of pre-existing structures, accommodation zone- and fault damage zone-related deformation are among the main factors that influence the spatial variation of fault network properties both at a regional and local scale. This study provides a new, but complementary way of characterising large-scale structural domains in rift systems. Additionally, our assessment of fault network topology provides important insights into the connectivity of rift-related normal faults, which have implications when considering the integrity of structural traps and subsurface fluid flow related to hydrocarbon and geothermal reservoirs, and CO2 storage.
Framework development and flag-based quality control for a national scale dataset using UK's Historical 15-Minute Flow Data
Authors: Fileni Felipe , J. Fowler Hayley , Lewis Elizabeth , McLay Fiona , Yang Longzhi
Published: March 2024

The United Kingdom has an extensive repository of 15-minute flow data dating back to the 1930s, yet this wealth of information has remained decentralized within respective measuring authorities responsible for localized quality control. Consequently, the absence of standardization has resulted in heterogeneous data records. Several discrepancies can be observed, ranging from minor issues such as having different decimal places, to bigger issues such as having duplicate records with different values or having different quality codes in the data.In the aim of producing a quality assured and consistent 15-min flow dataset for the whole UK, data has been requested from all UK measuring authorities. The data collected laid the groundwork for the development of a quality control framework, featuring both traditional, amply academically used and UK specific quality control flags. These flags have been used to standardise the data and produce a quality assured 15-min flow dataset for the UK.More than 1000 stations and tens of thousands of years of data have been passed through different flags aiming to identify data and stations that have suspicious data. 14 flags have been generated in the framework. The flags vary in complexity and aim to provide better understanding of the data.  Even simple flags, such as detecting negative values serve multiple purposes: from identifying tide-influenced stations characterized by negative flows, to using the flag to remove/replace the negative values for hydrological analysis.  Conversely, complex hydrology flags such as identifying large flow events preceded by large rainfall events or identifying the relationship between the high flow of stations in the same river can be used for an enhanced comprehension of hydrological systems at a national scale.This presentation aims to elucidate the flags that have been applied to the data; spotlight interesting case studies discovered in the quality control process; and showcase the versatile applications of the flags in data selections for specific hydrological analysis. In this PICO we want to emphasize the pivotal role that appropriate data selection has in shaping robust conclusions in the field of large sample hydrology.
Refining the Representation of Forest Management Practices in JSBACH4 
Authors: Räty Meri , Lessa Derci Augustynczik Andrey , Pongratz Julia
Published: March 2024

Fostering sustainable management of forests is pivotal in advancing Europe's climate resilience and achieving its short- and long-term environmental objectives. Any management strategy has multifaceted impacts, influencing carbon cycling and also leading to biogeophysical consequences arising from altered energy partitioning in the forest, for example. Modelling can offer valuable insights into these complexities, making it a beneficial tool aiding the pursuit of science-based solutions to inform policy and decision-making processes.  This work introduces improvements in the representation of wood harvesting and different forest management scenarios in JSBACH4, the current version of the land component of the ICOsahedral Nonhydrostatic Earth System Model (ICON-ESM) framework. The previously established forest age class scheme of JSBACH 4 and the extensive forest parameters and harvesting schemes from the model G4M-X (by the International Institute for Applied Systems Analysis) are utilised in the development.  This combination of a detailed forestry model integrated into decision-making frameworks, coupled with an advanced land surface model intricately linking to the entirety of key climate processes, holds great potential to enhance our understanding for the management of ecosystems. The objective of this effort is to enhance the sophistication of the related forest parameters in JSBACH4, enabling a more comprehensive simulation of various forest management scenarios.  This will allow capturing the nuanced carbon cycling and biogeophysical effects associated with different types of forest management and wood harvesting practices.
Understanding the Effectiveness of Scour Mitigation Techniques at Offshore Windfarms Using Experimental Modelling
Authors: Bradbury Maisy , McLelland Stuart , Dorell Robert , Marten Kerry , Whitehouse Richard
Published: March 2024

Over the last three decades the offshore wind energy sector in the UK and globally has grown rapidly and the recent COP28 climate summit reinforced the North Sea Collaboration (NSEC) on the development of offshore wind which targets an installed capacity of at least 260 GW of offshore wind energy by 2050. Due to this accelerated demand for offshore wind there has been increased demand for research on scour around subsurface structures in the offshore environment. It is also beneficial to minimise the influence of subsurface foundations on the marine ecosystem and therefore scour mitigation methods that enhance marine habitats would be advantageous. This study uses experimental modelling to explore the impact of scour mitigation around monopile foundations and evaluate successful methods whilst considering the habitats living around the offshore structures.Currently rock armour is most commonly used as an optimised scour protection layer for creating biodiversity enhancements. In this study four different scour mitigation techniques were assessed to analyse their effectiveness for scour mitigation; Textured Collars, Rock Dumping, Textured Piles and Rock Bags. All four scour mitigation techniques investigated have additional bio-enhancement capabilities and can be classed as a ‘Nature Inclusive Designs’ used to promote marine biodiversity and seaweed planting.  These scour mitigation methods include both dynamic and flow altering strategies using both the sea floor area around the monopile foundation and the foundation surface itself.  The experiments measured scour development under two different flow conditions until an equilibrium bed state developed. In some experiments, a novel Mylar Film technique was used to enable continuous measurement of scour development through structures being tested whilst simultaneously preventing water and sediment transfer. The results shown in Figure 1 suggest that under low flow conditions rock dumps and textured collars are the most effective scour mitigation technique to reduce scour depth. Textured collars prove to be the most successful for reducing scour depth under both flow conditions tested in these experiments.
Operational SSUSI Aurora Forecast Model 
Authors: Hsieh Syau-Yun , Zhang Yongliang , Schaefer Robert , Paxton Larry
Published: March 2024

Particle precipitation in the auroral oval serves as an important connection between the magnetosphere and ionosphere/atmosphere.  It is an important source of energy for the high-latitude upper atmosphere.  Particle precipitation not only creates extra ionization in the high-latitude ionosphere which leads to absorption and disturbances in radio communication, but also enhances the Joule heating by creating the Hall and Pedersen conductivity which alters the thermospheric convection and composition and further causes the global ionospheric disturbances.   To accurately characterize the auroral region energy inputs and conductivity is essential for improving the current capability for nowcasting and forecasting the ionospheric conditions in the high latitude region for space weather. The SSUSI Aurora Forecast Model is an FUV-based aurora forecast model.  It has been used operationally for predicting the global auroral quantities using the input remote-sensing ultraviolet measurements from the DMSP/SSUSI instruments.  The model predicts the equatorward boundary of auroral oval and precipitating the electron energy flux and mean energy estimated based on the empirical GUVI global model for up to 1 day or 15 DMSP orbits in advance.  We present the current implementation, capability and forecast results of this operational forecast model.  We will also discuss the current improvement and future development.