bluuebunny/crossref_metadata_2025 huggingface dataset:
Enriching the inclusivity of geophysical data communication using tactile resources 
Authors: Booth Adam , Holt Raymond , Thomas Briony
Published: March 2024

There is an increasing demand on the geoscience community for effective dissemination of data and inferences, equitably engaging a wide audience with communication resources. Geophysical surveys are widely applied to image subsurface structures, in disciplines spanning archaeological mapping, delineating environmental and engineering risk, and resource assessment. Many of these disciplines are of great interest to public stakeholders, whether they inspire curiosity, inform local planning decisions or extend to government policy.  

As informative as geophysical images can be, they are almost exclusively presented in visual formats. Our project explores how geoscience engagement can be enriched for users with a visual impairment and/or neurodiverse condition, by converting geophysical images into tactile surfaces. Working with a local heritage agency (Barnsley Museums, UK), our initial prototypes are tactile versions of geophysical data acquired over buried industrial archaeology at the Yorkshire village of Elsecar. Through a series of co-creative interviews, we are appreciating the requirements of visually-impaired users and progressively refining the design of the tactile models – while ensuring that production remains practical (i.e., cost effective, durable product). A key consideration is the amount of detail in a dataset that can be appreciated by touch alone, requiring a balance to be struck between offering the full complexity of the geophysical dataset versus presenting a simplified interpretation. Other issues to consider include ensuring sufficient relief such that features can be discerned (workshops suggest 4 mm is both effective for a user, and practical from a manufacturing standpoint), and how to convey distance and orientation.  

Three fabrication materials have been tested to date: plywood, swell paper and acrylic. Although plywood is cheap, it proves to be insufficiently robust and carries a grain that distracts from the features of interest. Swell paper (paper which, when heat-treated, swells to produce a low-relief topography) is also cheap, and may be valuable for large-scale outreach in which the outreach resources can be considered disposable (e.g., newsletters, schools programmes, etc). Acrylic shows the most promise for permanent installations, such as in museum exhibits: while expensive, it is robust and durable, and its translucency means it could be backlit to exaggerate contrast for users with residual sight. 

We envisage presenting tactile models of the archaeological site in Barnsley Museums’ exhibits, but our broader aim is to define a series of design considerations that would allow any geophysical dataset to be effectively reproduced as a tactile surface.  
Exploring the Relationship between CT Scanning Resolutions and Sandstone Porosity for CCS Applications
Authors: Huang Jyh-Jaan Steven , Liou Yao-Ming , Kioka Arata , Yang Tzu-Ruei
Published: March 2024

In the context of Carbon Capture and Storage (CCS), the porosity of potential storage formations is a critical factor. Our study explores this aspect using computed tomography (CT) to assess how different scanning resolutions impact the accuracy of porosity measurements. We employed three CT systems - Geotek RXCT (resolution ~20-150 μm), Bruker 1272 (resolution ~5 μm), and DELab μCT-100 (resolution ~9 μm) - to scan sandstone cores of varying porosities. The aim was to identify an optimal scanning resolution that balances detail with practicality for CCS evaluations.This research addresses the challenges in high-resolution CT scanning, such as denoising effects that can alter accuracy, and the complexities of thresholding segmentation across various systems. Additionally, we examined the partial volume effect, crucial for interpreting pore sizes and distributions accurately.Our preliminary results suggest that scanning resolution significantly affects the perceived porosity. Different resolutions uncover diverse aspects of pore structure, highlighting the importance of choosing an appropriate resolution. Advanced image processing techniques, including effective denoising and accurate thresholding, are vital for reducing errors in porosity measurement.The study provides valuable insights into the use of CT scanning for CCS applications, emphasizing the need for a balanced approach in resolution selection and sophisticated image processing. These findings are instrumental in enhancing the reliability of geological evaluations for potential CCS sites, contributing to the broader efforts in carbon storage and climate change mitigation.
Sustainable geothermal energy for two Southern Italy regions: geophysical resource evaluation and public awareness 
Authors: Amoroso Ortensia , Giampaolo Valeria , Balasco Marianna , Blasone Massimo , Bubbico Davide , Capuano Paolo , De Martino Gregory , Gargiulo Maria Vittoria , Napolitano Ferdinando , Perrone Angela , Panebianco Serena , Russo Raffaella , Serlenga Vincenzo , Stabile Tony Alfredo
Published: March 2024

This work shows the first results of activities carried out in the framework of project TOGETHER - Sustainable geothermal energy for two Southern Italy regions: geophysical resource evaluation and public awareness financed by European Union – Next Generation EU (PRIN-PNRR 2022, CUP D53D23022850001).The deployment and sustainable use of Italy's geothermal resources could represent a key asset to increase renewable energy production and reduce greenhouse gas emissions in the years ahead. Within this context, there is an obvious need for programs to improve subsurface geothermal resource extraction while maintaining environmental sustainability.Assessing the potential exploitation requires knowing the type of geothermal system, the likely temperature and characteristics of the reservoir rocks and fluids. We propose a novel geophysical multi-messenger approach, which provides unique and useful insights into the features and activities of examined geothermal reservoirs. These findings stem from the complementary information carried by subsoil geophysical parameters such as electrical resistivity and elastic/anelastic characteristics related to fluid presence. The proposed method will be tested in two test regions in Southern Italy that are appropriate for low to medium-enthalpy geothermal extraction: Contursi Terme and Tramutola. Contursi Terme is one of the most appreciated thermal sites in the whole Campania region. Here, 77 springs with temperatures ranging from 21°C to 30°C are present; furthermore, 72 shallower and deeper wells for the pumping of hot waters with temperatures ranging from 38°C to 43°C are used for balneotherapy. The Tramutola test site is located on the western side of the Agri Valley (Basilicata region) which hosts the largest onshore hydrocarbon reservoir of Western Europe. During the drilling of the "Tramutola2" well (404.4 m) in 1936, a significant volume of sulphureous hypothermal water (28 °C with a flow rate of 10 l/s) with accompanying gases (mostly CH4 and CO2) was discovered.At the same time, TOGETHER project aims to develop and apply communication methodologies devoted to increasing the acceptance of the exploitation of geothermal energy. This objective will be accomplished by actively engaging local communities and younger generations, who will serve as the foundation for scientific education, social interaction, and constructive debate.
High-resolution air temperature modeling during the summer 2022 heat waves over Dijon
Authors: Berger Alexandre , Crétat Julien , Pergaud Julien , Pohl Benjamin , Poupelin Mélissa , Richard Yves
Published: March 2024

Centre de Recherches de Climatologie/Biogéosciences, Université de Bourgogne, Dijon, France - alexandre.berger@u-bourgogne.fr2Laboratoire ThéMA, Université de Bourgogne, Dijon, France Heat waves (HWs) become more frequent, severe and longer under climate change. In cities, their impact is exacerbated by urban heat islands (UHIs). Proposing efficient adaptation plans necessitates upstream studies to further understand air temperature space-time variability within cities during HWs, their drivers, and associated mechanisms and processes.This study aims at understanding 2 m air temperature (T2m) space-time variability during the four HWs that occurred in Dijon during summer 2022 based on the dense MUSTARDijon network of 92 thermometers. We used a 150 m mesoscale simulations performed with the Meso-NH atmospheric model coupled with the TEB and ISBA surface schemes optimized for urban and rural environments, respectively. First, we evaluate the capability of Meso-NH to simulate the diurnal cycle of T2m for the four HWs over urban and rural environments. We show that Meso-NH more skillfully simulates the T2m diurnal cycle over urban than rural environments, despite a systematic cold bias in early morning and late afternoon. Second, we focus on the drivers of T2m space-time variability by using different predictors including land cover, energy budget, soil and atmospheric humidity and atmospheric dynamics. Buildings and roads contribute to warm the urban environment mostly at night, but these contributions are exaggerated by Meso-NH during all HWs. By contrast, vegetation contributes to cool the urban environment all day long for low vegetation and at night only for high vegetation in both observations and simulations. Also, wind speed seems having a strong impact on UHI intensity.
Informing the selection of mooring and anchor systems for floating offshore wind farms based on a review of existing projects
Authors: Amjadian Pegah , Creane Shauna , Coughlan Mark , O' Donovan Christopher , Zhao Budi , Long Mike , Keenahan Jennifer
Published: March 2024

National and international climate objectives, along with sustainable development targets, are driving the rapid growth of the offshore renewable energy sector. At the forefront of this industry is offshore wind. While fixed offshore wind technology has reached maturity, its application is limited to water depths of 60 meters, restricting access for nations interested in adopting offshore wind solutions. Hence, the wind industry is actively pursuing the advancement of floating offshore wind technology.Choosing the right floating foundation, mooring systems, and anchors for a project is crucial and it is vital to customize and optimize of the design of these systems based on site-specific factors like water depth, environmental conditions, and seabed morphology. These systems play a critical role in securing the turbine during severe environmental events and contribute, alongside the floating platform, to the overall hydrodynamic stability. In addition, the lifespan of a floating offshore wind turbine is greatly influenced by the selection of a reliable mooring system and anchor type, emphasizing potential cost savings compared to systems requiring mid-life line replacements with higher operational costs.This research is set to address a significant gap in our knowledge by creating a decision matrix for selecting mooring and anchor setups in floating offshore wind projects. Furthermore, we'll address certain challenges associated with floating structures, like sediment mobility and interactions of structures with the seafloor, which can pose significant risks to marine structures. These issues are often primary factors that risk the stability and integrity of offshore structures in marine and coastal environments. Investigating and modelling these phenomena are essential steps to minimize the risk of failure in projects. The process involves carefully studying successful past projects, closely examining the geotechnical data and seabed condition, metocean data, and thoroughly evaluating how the platforms are designed.Furthermore, the study also considers the Atlantic Marine Energy Test Site (AMETS), a crucial project led by the Sustainable Energy Authority of Ireland (SEAI), offering valuable insights as an illuminating case study for potential future projects. This study will conduct an extensive review to assess various types of anchors that could be suitable for our designated study area. By integrating insights from prior projects and gaining a nuanced comprehension of water movements, we aim to make thorough and well-informed decisions regarding optimal parameters. These parameters encompass crucial aspects such as location, water depth, foundation type, and mooring specifications.Keywords: floating offshore wind foundation, mooring, anchors, sediment mobility  
Molecular characterization of the sedimentary organic matter deposited off central Peru (12 – 14ºS): first insights into preservation processes
Authors: Igarza Maricarmen , Graco Michelle , Boussafir Mohammed , Sifeddine Abdelfettah , Valdés Jorge , Gutiérrez Dimitri
Published: March 2024

Phytoplankton production represents the ultimate source of organic matter in the ocean; thus, the study of organic compounds can give us information related to organic matter (OM) origin and transformations. Usually less than 1% of the OM produced in the ocean surface reaches the seafloor, although in highly productive regions nearly 10% can be buried and subjected to further degradation. The Peruvian upwelling system is among the most productive marine ecosystems in the world ocean, with high primary production sustained mainly in a year-round upwelling. Along the Peruvian continental margin, variations in primary production, bottom dissolved oxygen, and depth influence OM accumulation and preservation, and thus determine the existence of different depositional environments. Previous geochemical and palaeoceanographic studies have shown that the best records of well-preserved OM are found towards the central area of the Peruvian continental margin, between 12°S and 14°S. Therefore, the study of organic compounds, particularly lipids, deposited in surface sediments could give us information regarding early diagenetic processes related to OM degradation/preservation. The objective of this study was to characterize both the solvent extractable OM fraction (i.e. free lipids) and the insoluble OM fraction (i.e. protokerogen) in order to elucidate possible preservation mechanisms involved in OM accumulation. A total of 14 surface sediment samples from different locations between 12°S and 14°S were analyzed by means of gas chromatography mass spectrometry. Organic compounds such as short-chain and long-chain alkanes and fatty acids were quantified in the solvent-extractable OM fraction, which allowed the calculation of a pristane/phytane index and a carbon preference index. In the insoluble OM fraction, alkanes and fatty acids were also quantified together with dithiophene and benzothiophene compounds and organic sulfur heterocompounds. Overall, our results allowed a detailed geochemical molecular characterization of the OM deposited in surface sediments beneath one of the most productive areas of the Peruvian coast. The differences observed in both the n-alkane and fatty acids distribution between the solvent-extractable OM fraction and the insoluble OM fraction, together with the quantification of sulfur compounds in the insoluble fraction, suggests that complex diagenetic processes occur in surface sediments. An important part of the freshly-produced OM in the highly productive surface waters off central Peru reaches the seafloor and undergoes preservation mechanisms mainly related to natural sulfurization and selective preservation, tightly coupled to the reduced conditions that characterize surface sediments in the area.
Quantifying the Impact of Dynamic Lapse Regimes on Spatially-Distributed Snow Simulations
Authors: Whitney Kristen , Kumar Sujay , Bolten John , Pflug Justin , Maina Fadji , Hain Christopher , Mocko David , Wrzesien Melissa
Published: March 2024

Accurate characterization of surface meteorological distributions over coastal areas and complex terrain, especially the relationship between temperature and altitude, is essential for the accurate simulation of snowpack dynamics. This becomes increasingly difficult at spatial resolutions smaller than common gridded meteorological forcing datasets due to the sparsity of long-term temperature measurements and the influence of local factors like cool air pooling and inversions. Near-surface air temperatures (Ta) are often assumed to decrease with elevation at a constant rate of 6.5oC km-1, which could lead to large model errors in snow evolution and other processes key to snow hydrology, water resource management, and other applications. This study evaluates the impact of local dynamical adjustments to downscaled Ta on snow simulations over two coastal mountainous terrains using the Noah-MultiParameterization (NoahMP) land surface model. Forcings are derived from remote sensing and reanalysis precipitation products and the (Modern-Era Retrospective Analysis for Research and Applications, version 2) MERRA-2 atmospheric products (including Ta) at the downscaled 1-km resolution. Hourly lapse rates at each grid cell are calculated by applying linear regression to Ta and elevation from surrounding grid cells (within one grid lengths in the x or y direction) at the Ta native MERRA-2 resolution and applied to the downscaled 1-km Ta product. We will present the impact on simulated snow water equivalent, snow cover, and snow depth across simulations forced with the downscaled Ta (1) without lapse rate correction, (2) corrected with a constant lapse rate (6.5oC km-1), and (3) corrected with the dynamic hourly lapse rate. Results will be compared against remote sensing-based products.
Global terrestrial ecosystem resilience: a high-resolution multivariate analysis of patterns and drivers
Authors: Knecht Nielja , Fetzer Ingo , Rocha Juan
Published: March 2024

Natural terrestrial ecosystems in different parts of the world have been losing resilience in the past decades. Such losses of resilience can be the precursors for regime shifts on local or regional scales that can have large impacts on ecosystem structure and function as well as nature’s contributions to people. Drivers of resilience loss include mainly changes in the mean and variability of temperature and precipitation, and anthropogenic land modifications of adjacent or remote ecosystems.Global assessments of ecosystem resilience often exclude areas with direct anthropogenic land use changes and focus instead on remnant natural ecosystems. However, for regional stakeholders it is important to understand how land-use and zoning decisions may affect the resilience of remaining ecosystems and the risk of critical transitions.In this study, we conduct a high-resolution global assessment of terrestrial ecosystem resilience losses, using time series of multiple remotely-sensed ecosystem indicators, and employing a range of early warning signals. We also evaluate the importance of different climatic and anthropogenic drivers at a local scale of administrative units in causing the detected changes in resilience. This allows us to get a comprehensive and robust understanding of different dimensions of change in global ecosystem resilience and their locally relevant drivers of change.
Accuracy of agricultural drought indices and analysis of agricultural drought characteristics in China between 2000 and 2019
Authors: Pan Ying , Xu Haiting
Published: March 2024

Agricultural drought threatens global water security, food security, and natural ecosystems. Accurate identification of agricultural drought is a crucial task to mitigate its consequences. However, it is challenging to achieve reliable and accurate regional agricultural drought assessment in both wet and dry climates at the same time. Therefore, the objective of this study is to identify a reliable and accurate agricultural drought index that performs well in both dry and wet climates. Drought indices such as the Standardized Precipitation Index (SPI), the Vegetation Condition Index (VCI), the Soil Moisture Anomaly index (SMA), and the Drought Severity Index (DSI) were calculated and compared against in situ drought information devised by official sources in China. The results showed that: (1) DSI based on the Global Land Data Assimilation System (GLDAS) products performed the best in identifying agricultural drought in both dry and wet climate regions of China. (2) Agricultural regions such as Northern arid and semiarid regions, Northeast China Plain, Huang-Huai-Hai Plain, and Loess Plateau, experienced moderate and severe agricultural droughts with a frequency of 20%. (3) The frequency of agricultural droughts observed in Northern arid and semi-arid regions and Northeast China Plain has slowed significantly over the last two decades with a significance level of 0.01. On the other hand, the number of agricultural droughts has increased in Yunnan-Guizhou Plateau since 2002.
The i-FSC proxy for predicting near-source topographic site effects and studying earthquake-induced landslide distributions
Authors: Bou Nassif Aline , Maufroy Emeline , Lacroix Pascal , Chaljub Emmanuel , Causse Mathieu , Marc Odin , Bard Pierre-Yves
Published: March 2024

During earthquakes, a high degree of spatial variation in damage distribution, encompassing both structural damage to buildings and co-seismic landslides, is commonly observed in mountainous regions near the seismic source. Among other factors, this spatial variability can be partly attributed to the amplification of seismic waves caused by surface topography. Our study focuses on predicting ground-motion amplification due to topography in close proximity to earthquakes and examining its potential influence on co-seismic landslide distribution patterns.To achieve this goal, we employ neural network analysis on previously available synthetic data from 3D finite-differences simulations of seismic wave propagation. The analysis aims at developing a physics-based estimator of topographic site effects in close distances to the source, referred to as the i-FSC proxy (Illuminated Frequency Scaled Curvature). This proxy depends on the S-wavelength, the curvature of the topographic surface, and a new parameter called the "normalized seismic illumination angle", which quantifies the slope's exposure to the incoming wavefield. The inclusion of the illumination parameter substantially decreases the uncertainties of the proxy by a factor of 2 compared to estimators that rely solely on curvature as a key parameter. The i-FSC proxy is a user-friendly tool that does not require high computational resources; it utilizes only a digital elevation map and the position of the seismic source to predict amplification factors at any point on the surface topography. This estimator allows exploring the spatial variations in topographic amplification caused by nearby seismic sources, representing a significant breakthrough as areas closest to the fault typically sustain the most damage during earthquakes.Subsequently, the i-FSC proxy is used to investigate the correlation between ground-motion amplification and the spatial distribution of earthquake-induced landslides triggered by large events such as the 2015 Gorkha earthquake (MW 7.8). The results indicate that more than 71% of co-seismic landslides tend to be localized in amplified areas. Different physical controls on the landslide triggering at different frequencies have been identified. The results also highlight the crucial importance of considering the effect of topographic amplification, together with other classical factors such as slope steepness, for a better understanding of the complex mechanisms governing the spatial distribution of earthquake-induced landslides at local and regional scales. The obtained results could provide valuable insights for future researches, guiding efforts towards more effective risk assessment and mitigation strategies in mountainous regions.
The FLARE Workshop's Future Directions for Defining Extreme Fire
Authors: Liguori-Bills Noah , Perron Morgane , Plummer Stephen , Voelker Christoph , Vannière Boris , Hall Joanne , Forkel Matthias , Dintwe Kebonye , Santin Cristina , Morrill Miriam , Thoreson Jessie , Poulter Benjamin , Jones Matthew , Kelley Douglas , Burton Chantelle , Hantson Stijn , Hamilton Douglas
Published: March 2024

In September 2023, the Fire Learning AcRoss the Earth Systems (FLARE) workshop brought together fire scientists across a wide range of disciplines, including physical and social scientists and representatives of fire-prone communities, with the aim to facilitate a transdisciplinary discussion. The FLARE community identified characterizing “fire and extreme events” as a research priority. In recent years, there has been a rise in extreme weather events worldwide. Both in science and in the media, the word “extreme” is increasingly used to describe the impact of natural phenomena on ecosystems, human health, the carbon cycle, and economies. However, the severity associated with recent changes in fire activity is not well defined. Assessing the cause(s) and consequences of a fire event on a global scale is complex, this leads to different definitions and assessment techniques/methods being used in the range of disciplines that study fire, including ecology, biology, hydrology, atmospheric science, marine science, Earth science, or public health. Additionally, it is hard to disentangle human land management and climate change induced changes in fire regimes. Using examples from the 2023 Boreal fires, this presentation discusses future directions for defining extreme fires. Fires are also part of the broader interconnected Earth System and influenced by droughts, heat waves, and altered landscapes. In turn, post-fire effects such as erosion, landslides, and floods create cascade events that impact both human societies and natural ecosystems. We discuss this broader view of including fire extremes as part of compound extreme events in order to fully assess their impact. We finish by providing recommendations for the fire science community to tackle this challenge. Some of which may include more proactive modeling, observation and communication tools aimed at providing relevant and timely information. https://futureearth.org/2023/12/13/reflections-from-the-fire-science-learning-across-the-earth-system-flare-workshop/
Deep lithospheric controls on the formation and evolution of the East Anatolian Fault Zone and Anatolia-Arabia-Africa Triple Junction
Authors: Delph Jonathan , Darin Michael , Whitney Donna , Cosca Michael , Teyssier Christian , Eken Tuna , Kaymakci Nuretdin , Reid Mary , Beck Susan
Published: March 2024

The North and East Anatolian Fault Zones represent plate-bounding transform faults that enable the westward tectonic escape of the Anatolian Plate away from the Arabian-Eurasian collisional zone. These fault zones are both capable of hosting large (Mw > 7) seismic events, as most recently demonstrated by the extremely damaging February 2023 Kahramanmaraş earthquake sequence. This earthquake sequence highlighted that plate boundary forces in this area are distributed over a very broad region, however what controls the location, distribution, and character of this plate-bounding strike-slip system remains enigmatic. To better understand potential contributions to deformation, we compare seismic images of the lithosphere (e.g., crustal and lithospheric mantle thickness and velocity) to deformational features and seismicity near the EAFZ, as well as further west where it joins with the Anatolia-Arabia-Africa (A3) triple junction along the southeastern margin of the Anatolian escape system. We interpret that although controls on surface deformation are commonly linked to stress in the brittle upper crust, the complex deformation and seismicity patterns in this region are likely related to variations in the location and extent of the strong lithospheric mantle of the Arabian plate, which currently underthrusts Anatolia as far north as the Sürgü-Çardak fault zone (~50 km). In addition, the Arabian lithospheric mantle extends at least as far west as at least the central Adana Basin, coincident with a zone of relatively deep (>30 km) strike-slip seismogenesis that has produced Mw > 6 earthquakes. By investigating the relationship between recent geological deformation since the inception of the East Anatolian Fault (ca. 5 Ma) and the modern record of seismic structure and seismicity, we infer that the Sürgü-Çardak fault zone and its associated near-orthogonal bend reaching into the Adana Basin will be the future southeastern boundary of the Anatolian Plate escape tectonic system.
Development of a model agnostic isotope tracer simulator 
Authors: Holmes Tegan , Stadnyk Tricia , Pietroniro Alain
Published: March 2024

Isotope tracers can benefit hydrologic modeling, by adding observational data relating to evaporation and water ages as a supplement to flow data. A few hydrologic models have had tracers embedded in their software, resulting in numerous studies and identified benefits from isotope tracer simulation. A key barrier to more wide-spread application of linked flow and isotope simulation in hydrologic modeling is the considerable effort required to add an isotope tracer simulation to an existing model, which requires an uncommon overlapping expertise in both hydrologic model development and isotope tracer science. To expand the utilization of isotope tracers, a model agnostic isotope tracer simulator (MAITsim) has been developed, which can currently simulate two common stable isotope tracers (deuterium and oxygen-18) in association with a wide range of hydrologic models. 

MAITsim runs as a post-processing model using outputs from a hydrologic model as inputs, such that only the model specific linkage needs to be set up in order to simulate both flow and isotope tracers. The tracer simulator is compatible with any flux-state model with unidirectional flow paths, as it uses no pre-determined spatial sub-divisions (any combination of soil layers, sub-catchments and hydrologic response units can be linked to MAITsim). The model includes both mixing and evaporative fractionation and is designed to be numerically stable in wet and desiccating conditions. 

The MAITsim model results are compared to an existing embedded isotope tracer model (isoWATFLOOD). The next phase in development is to test MAITsim functionality and performance in multiple existing hydrologic models. 
Global Distribution of Mountainous Headwater Catchments Morphology
Authors: Wu Pengfei , Liu Jintao , D'Agostino Vincenzo
Published: March 2024

Mountainous regions are important headwater regions to sustain environmental and human water demands. The morphologies of these headwater catchments control their hydrological response and affect the water supply to downstream. In this study, more than 3.3×107 headwater catchments are extracted. These cover most of the mountainous regions between 60°S and 60°N and their areas range from 0.5 km2 to 2 km2. Several morphological features closely related to hydrological response and sediment dynamics, such as width function and Melton number, are estimated for the catchments. Particularly, in order to ensure the accuracy of the estimated parameters, two new algorithms are developed, including an improved triangular form-based multiple flow direction algorithm as well as a width function algorithm based on a two-segmented-distance strategy and the multiple equidistant belt technique. Subsequently, a dataset of mountainous headwater catchment morphology is generated by adding the climatic and tectonic features corresponding to each catchment. This dataset can help to identify the hydrological similarities between different headwater catchments, which is important for determining the parameters of hydrological models in ungauged catchments. We analyze the relationship between the catchment morphology features and tectonics (e.g., shortening rate) as well as climate variables (e.g., precipitation and temperature). The results show that great differences exist in catchment morphology between tectonically active areas and inactive areas. Furthermore, the relationship between morphology and climatic variables varies depending on the lithology of the region, with the strongest correlation observed in sedimentary regions.
High-resolution topographic surveys of five upland river realignment schemes show restoration increases and maintains geomorphic unit diversity at the decadal scale
Authors: Williams Richard , Reid Helen , MacDonell Craig , Caithness Fiona , Gillies Eric , Moir Hamish
Published: March 2024

River restoration is key to realising ambitions to improve the biodiversity of rivers and to contribute to natural flood risk management. However, a dearth of detailed, accurate and consistently acquired, long-term topographic monitoring constrains the available evidence base to evaluate the efficacy of different river restoration approaches. Upland gravel-bed river realignment schemes are emblematic of this challenge. Here, the results from monitoring five contemporary upland river restoration sites in Scotland and the North-West of England are presented. The topography of 9 km of restored reaches at Whit Beck, the River Lyvennet, Swindale Beck, Allt Lorgy and the River Nairn was measured for a period of approximately one decade after each river realignment. The full extent of each scheme was surveyed every 1-3 years, with the frequency dependent on the geomorphic dynamism of the scheme. A variety of geomatics technologies were deployed to survey topography including, robotic total stations, RTK-GNSS, Structure-from-Motion photogrammetry, Terrestrial Laser Scanning and Unmanned Aerial Vehicle LiDAR. This unique dataset has enabled geomorphic change to be mapped and annual sediment fluxes to be quantified. Moreover, the high-resolution topographic datasets enable the geomorphic unit development of each scheme to be mapped using the Geomorphic Unit Toolbox (GUT). Together, this dataset enables three questions to be investigated: (i) what is the geomorphic unit composition of restored rivers?; (ii) how does geomorphic unit diversity develop post-restoration; and (iii) what geomorphic mechanisms are sustaining geomorphic unit diversity? We show that different restoration schemes have contrasting geomorphic unit assemblages, which are influenced by sediment supply, scheme constraints, in-channel and riparian wood and vegetation, and intervention through adaptive management approaches. The sediment budget for Swindale Beck exemplifies the trend in total volumetric topographic change through time; change is greater in the first few years following restoration and then declines once the river has adjusted the imposed boundary conditions. Topographic change initially increases the aerial extent of geomorphic units, the aerial extents of erosion and deposition between surveys then become similar and the extent of the active river channel remains approximately constant. Overall, across all schemes, there is declining geomorphic change with time but geomorphic unit, and thus physical habitat, diversity are maintained. These findings provide strong evidence for how physical habitat diversity and quantity have both increased and been maintained as a consequence of river realignment and should underpin efforts to scale up from demonstration sites to catchment-scale restoration efforts.
Wind erosion rates in the Arctic as recorded the roots of tundra shrubs  – a new dendrochronological approach
Authors: Owczarek Piotr , Opała-Owczarek Magdalena , Dagsson-Waldhauserova Pavla , Schaetzl Randall J. , Migała Krzysztof
Published: March 2024

Arctic and sub-Arctic terrestrial environments often have bare surfaces, thin and poorly developed soils, large amounts of loose sediment, and low and sparse vegetation. The sensitivity of these sites to modern climate change is reflected, among other things, in an increase in the activity of erosion processes mainly via deflation. Despite the development of modern research tools and monitoring methods, the temporal and spatial changes in the intensity of soil degradation by aeolian processes in high latitude environments is still poorly understood. In this study, we sought to determine soil erosion rates, using anatomical features of Arctic shrubs and dwarf shrubs in northeastern Iceland, central Spitsbergen, and southern Greenland. The main research question we posed was: can the dendrochronological information contained in the anatomy of shrub roots be used to reconstruct soil degradation and erosion histories? We applied dendrochronological techniques to the exposed roots of dwarf willow (Salix herbacea L.), net-leaved willow (Salix reticulata L.), and common juniper (Juniperus communis L.), and estimated surficial erosion based on abrupt changes in cell size and width of annual growth increments in the roots. The accuracy of the dating of erosion processes was checked by comparison with dendrochronological reference scales from specimens collected from undisturbed site. We observed, that after exposure of shrub roots, cell size decreases by at least 50%, with the maximum changes in individual plants exceeding 150-200%. Based on this relationship, we estimated surficial erosion rates for Iceland (1970’s-present), as well as for Spitsbergen and Greenland (1980’s-present). We observed a rapid increase in erosion rates in the latter half of the 1990’s, approaching 5.4 – 6.1 cm/year. Our results confirmed the efficiency of the dendrochronological method we employed, for determining soil erosion rates, even in unforested areas. The method is particularly applicable to low-growing, Arctic dwarf shrubs, which develop measurable growth rings and cells, making them a reliable proxy in soil degradation studies.The research was founded by a Polish National Science Centre project no. UMO-2021/41/B/ST10/03381 and project no. UMO-2019/35/D/ST10/03137.
The Crevasse Depth Calving Law Applied to Ice Shelves: Insights from a 1D Flowline Model 
Authors: M. Nick Faezeh , Benn Doug
Published: March 2024

The crevasse depth (CD) calving law predicts the position of glacier termini from the penetration of surface and basal crevasses computed from stresses in the ice. When applied to Greenland tidewater glaciers, it has high skill when implemented in a full-Stokes 3D model, although its performance in 2D and 1D models is still subject to debate, especially its ability to induce ice shelf calving without the addition of unrealistic amounts of  water in surface crevasses.  This study re-evaluates the CD law within a 1D flowline model of an ice shelf. We show that the model predicts deep crevasse penetration at locations where drag at the shelf boundaries diminishes,such as the grounding line or embayment mouths. Crevasse depth depends on the rate at which these resistance sources decrease along-flow, influencing the longitudinal stress gradient. While full-depth penetration may occur in thinned shelves (due to extensive basal melt), full-depth calving is generally not predicted for unconfined ice shelves. Observations of Antarctic ice shelves and floating ice tongues well beyond embayments or basal pinning points suggest that additional triggers, like slow rift growth, basal melting, or oceanographic stresses, are essential for calving. The addition of water to surface crevasses can greatly facilitate calving. In some cases, reflecting real-world conditions, such as the hydrofracturing-induced collapse of vulnerable ice shelves. However, the need for water-depth tuning in other situations has raised concerns about the physical fidelity of the model. We propose a modified stochastic CD calving criterion in which the probability of calving ramps from zero for a threshold crevasse depth to one for full-depth penetration. This non-deterministic approach captures the statistical structure of calving events, and allows a range of observed behaviours to emerge, such as long Antarctic ice shelf calving cycles (ice-tongue advance punctuated by rare calving events), and short-term fluctuations of tidewater glaciers (frequent calving retreat back to pinning points). We argue that a probabilistic approach represents an important step towards a universal calving law.  
High-pressure aqueous systems: experimental constraints and thermodynamic models of fluid-mineral-melt equilibria
Authors: Dolejš David
Published: March 2024

Aqueous fluids are essential agents of mass transport and geochemical cycling in various magmatic, metamorphic orogenic and subduction settings. Thermodynamic properties of aqueous solutes at high pressure have been modelled using several approaches: (1) electrostatic models (Sverjensky et al. 2014), (2) density extrapolations (Wohlers et al. 2011; Manning 2013), or (3) density models (Dolejš and Manning 2010; Dolejš and Salomone 2023). Critical comparison of experimental and predicted mineral solubilities in aqeuous fluids over wide range of temperatures and pressures provides the most accurate constraints on the functional performance of these approaches. This evaluation reveals that (1) electrostatic models offer greater fitting flexibility at costs of extrapolation accuracy and stability across the pressure-temperature space; (2) density models are more robust, require fewer parameters at costs of accuracy at low-temperature conditions. With increasing pressure, the solute concentrations rise and approach the critical transition to hydrous melts. Solute-solvent interaction indicate that mineral-fluid equilibria during critical approach are initially far from congruent and this pressure-temperature region strongly promotes metasomatic effects. The infinite dilution formalism is not physically not suited for reproducing these solubility trends. Instead, thermodynamic description of the critical fluid-melt transition requires consideration of: (1) competing effects of solute polymerization vs. association (hydration) in the dilute region, (2) transition from flexible liquid medium to structured aluminosilicate framework, and (3) speciation mechanism of H2O in aluminosilicate melt. Using the model system H2O-SiO2 we demonstrate coupling between configurational, ideal and excess mixing effects using several molecular and structural formalisms. Use of universal thermodynamic conditions for critical point or curve effectively constrains the location of these phase diagram features and it reduces the number of independent parameters in the mixture equation of state.  In the simplest case, the solubility, melting and critical phase equilibria in the system H2O-SiO2 can be reproduced with a four-parameter equation of state for solute and one interaction parameter. These results reveal diverse heuristic aspects arising from classical thermodynamic constraints and indicate predictive capability and practical accuracy of these models for natural solute-rich fluids in high-pressure settings.References:  Dolejš D., Manning C.E., 2010. Geofluids 10, 20-40.  Dolejš D., Salomone F., 2023. Proc. 17th Bienn. SGA Meeting 1, 143-146.  Manning C.E., 2013. Rev. Mineral. Geoch. 76, 135-164.  Miron D. et al., 2017. Am. J. Sci. 317, 755-806.  Sverjensky D.A. et al., 2014. Geoch. Cosmoch. Acta 129, 125-145.  Sverjensky D.A., 2019. J. Geol. Soc. 176, 348-374.  Wohlers A. et al., 2011. Geoch. Cosmoch. Acta 75, 2924-2939.
Reconstructing Stratospheric Aerosol Loadings from Extratropical Eruptions
Authors: Burke Andrea , Sigl Michael , Cole-Dai Jihong , Innes Helen , McConnell Joe , Pearson Charlotte , Sugden Patrick
Published: March 2024

Extratropical eruptions have been associated with major cooling in the Northern Hemisphere over the last 2000 years (Toohey et al., 2019; Burke et al., 2023).  However, our ability to reconstruct the stratospheric aerosol loading from these events is limited by uncertainties in the conversion of sulfate flux to the polar ice sheets into a stratospheric sulfur loading or aerosol optical depth. Current methods (e.g. Gao et al. 2007; Toohey and Sigl, 2017) assume that all of the ice core sulfate from these eruptions is deposited via the stratospheric overworld, but sulfur isotope evidence shows that a substantial proportion of ice core sulfate comes via lower altitudes. Here we evaluate the magnitude of this complication across many of the major extratropical eruptions over the last several thousand years, including eruptions from the Katmai/Novarupta, Aniakchak, and Okmok volcanoes, and investigate the implications of these findings for stratospheric aerosol forcing records currently used in climate models.  Burke, A., Innes, H.M., Crick, L., Anchukaitis, K.J., Byrne, M.P., Hutchison, W., McConnell, J.R., Moore, K.A., Rae, J.W., Sigl, M. and Wilson, R., 2023. High sensitivity of summer temperatures to stratospheric sulfur loading from volcanoes in the Northern Hemisphere. Proceedings of the National Academy of Sciences, 120(47), p.e2221810120.Gao, C., Oman, L., Robock, A. and Stenchikov, G.L., 2007. Atmospheric volcanic loading derived from bipolar ice cores: Accounting for the spatial distribution of volcanic deposition. Journal of Geophysical Research: Atmospheres, 112(D9).Toohey, M. and Sigl, M., 2017. Volcanic stratospheric sulfur injections and aerosol optical depth from 500 BCE to 1900 CE. Earth System Science Data, 9(2), pp.809-831.Toohey, M., Krüger, K., Schmidt, H., Timmreck, C., Sigl, M., Stoffel, M. and Wilson, R., 2019. Disproportionately strong climate forcing from extratropical explosive volcanic eruptions. Nature Geoscience, 12(2), pp.100-107.
How multiple dikes facilitate volcanic eruptions, with application to recent events on the Reykjanes Peninsula, Iceland
Authors: Gudmundsson Agust
Published: March 2024

Dikes supply magma to most volcanic eruptions. Understanding under what conditions propagating dikes reach the surface to erupt or, alternatively, become arrested (stop their propagation) or deflected so as to propagate primarily laterally or change into sills, is thus one of the fundamental tasks of volcanology. Many dike segments injected from magma sources do not reach the surface to feed volcanic eruptions. Instead, the dike segments become arrested, commonly at or close to contacts between mechanically dissimilar layers/units, at various crustal depths. This means that many and perhaps most volcanic unrest periods with dike injections do not result in eruptions. There are several conditions in the crust that make dike arrest likely, but the main one is layering where the layers have contrasting mechanical properties. Such layering means that local stresses are heterogeneous and anisotropic and thus in some layers unfavourable (e.g., because the layers act as stress barriers) for vertical dike propagation, resulting in dike arrest, lateral dike propagation beneath the stress barrier, or dike deflection into a sill. Here I show that once a dike has formed, its very existence tends to make the local stress field along the dike homogeneous (with invariable orientation of principal stresses) and favourable (with dike-parallel orientation of the maximum compressive principal stress) for later dike injections. This means that a later-injected dike may use an earlier-injected dike as a path, either along the margin or the centre of the earlier dike, thereby generating a multiple dike. Because earlier feeder-dikes form potential paths for later-injected dikes to the surface, many volcanic eruptions are fed by multiple dikes. Multiple dikes thus tend to favour dike propagation to the surface, thereby facilitating dike-fed eruptions. Examples of multiple-dike-fed eruptions include recent ones in Etna (Italy) and Kilauea (Hawaii), as well as in the Icelandic volcanoes Krafla and Hekla. Here, however, the focus is on several eruptions in the past few years on the Reykjanes Peninsula, Iceland. In particular, I discuss the eruptions of 2021, 2022, and 2023 in the volcano Fagradalsfjall as well as the 2023 eruption along the volcanic fissure Sundhnukar (close to the town of Grindavik), all the eruptions occurring on the Reykjanes Peninsula.Gudmundsson, A., 2022. The propagation paths of fluid-driven fractures in layered and faulted rocks. Geological Magazine, 159, 1978-2001.Gudmundsson, A., 2023. Multiple dikes make eruptions easy. EarthArXiv, https://doi.org/10.31223/X5M67Q 