bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil data quality and resolution matter when predicting woody plant species in temperate forests
Authors: Rota Francesco , Scherrer Daniel , Bergamini Ariel , Price Bronwyn , Walthert Lorenz , Baltensweiler Andri
Published: March 2024

Soil properties influence plant physiology and growth, playing a fundamental role in shaping species niches in forest ecosystems. Here, we investigated the impact of soil data quality on the performance of climate-topography species distribution models (SDMs) of temperate forest woody plants. We compared models based on measured soil properties with those based on digitally mapped soil properties at different spatial resolutions (25m and 250m). We first calibrated SDMs with measured soil data and plant species presences and absences from plots in mature temperate forest stands. Then, we developed models using the same soil predictors, but extracted from digital soil maps at the nearest neighbouring plots of the Swiss National Forestry Inventory. Our approach enabled a comprehensive assessment of the significance of soil data quality for 41 Swiss forest woody plant species. The predictive power of SDMs without soil information compared to those with soil information, as well as those with measured vs digitally mapped soil information at different spatial resolutions was evaluated with metrics of model performance and variable contribution. On average, performance of models with measured and digitally mapped soil properties was significantly improved over those without soil information. SDMs based on measured and high-resolution soil maps showed a higher performance, especially for species with an ‘extreme’ niche position (e.g. preference for high or low pH), compared to those using coarse-resolution (250m) soil information. Nevertheless, globally available soil maps can provide important predictors if no high-resolution soil maps are available. Moreover, among the tested soil predictors,  pH and clay content of the topsoil layers improved the predictive power of SDMs for forest woody plants the most. Such improved model performance informs biodiversity modelling about the relevance of soil data quality in SDMs for species of temperate forest ecosystems. In conclusion, the incorporation of accurate soil information into SDMs becomes indispensable for making well-informed forecasts for guiding decisions in forest management, also when addressing the potential distribution shifts of woody plant species due to climate change.
MorSnowAI v1.0 : An Open-Source Python Package for Empowering Artificial Intelligence in Snow Hydrology - A Comprehensive Toolbox
Authors: Elyoussfi Haytam , Boudhar Abdelghani , Belaqziz Salwa , Bousbaa Mostafa , Nifa Karima , Bargam Bouchra , Karaoui Ismail , Bouihrouchane Ayoub , Benmira Touria , Chehbouni Abdelghani
Published: March 2024

Data-driven methods, such as machine learning (ML) and deep learning (DL), play a pivotal role in advancing the field of snow hydrology. These techniques harness the power of algorithms to analyze and interpret vast datasets, allowing researchers to uncover intricate patterns and relationships within the complex processes of snow dynamics. In snow hydrology, where traditional models may struggle to capture the nonlinear and dynamic nature of snow-related phenomena, data-driven methods provide a valuable alternative. Using data-driven methods (ML and DL) requires advanced skills in various fields, such as programming and hydrological modeling. In response to these challenges, we have developed an open-source Python package named MorSnowAI that streamlines the process of building, training and testing artificial intelligence models based on machine learning and deep learning methods. MorSnowAI not only automates the building, training, and testing of artificial intelligence models but also significantly simplifies the collection of data from various sources and formats, such as reanalyzing datasets (ERA5-Land) from Copernicus Climate Data and remote sensing data from Modis, Landsat, and Sentinel datasets to calculate Normalized Difference Snow Index (NDSI). It can also utilize local datasets as inputs for the model. Among other features available in the MorSnowAI package, it provides pre-processing and post-processing methods that users can choose, along with visualization and analysis of the available time series. The scripts developed in the MorSnowAI package have already undergone evaluation and testing in various snow hydrology applications. For instance, these applications include predicting snow depth, streamflow, snow cover, snow water equivalent, and groundwater levels in mountainous areas of Morocco. The automated processes within MorSnowAI contribute to advancing the field, enabling researchers to focus on refining model inputs, interpreting results, and improving the overall understanding of complex hydrological systems. By bridging the gap between hydrology and advanced data-driven techniques, MorSnowAI fosters advancements in research, offering valuable insights for resource management in regions heavily influenced by snow dynamics. 
Geochemical profiles in the hydrogeological system of the Opalinus Clay
Authors: Schleicher Anja , Bonitz Marie , Hennig Theresa , Stammeier Jessica , Jaeggi David , Kühn Michael
Published: March 2024

Opalinus Clay is the chosen host rock for the deep geological disposal of nuclear waste in Switzerland and is also being considered for this purpose in Germany. For the long-term integrity of the disposal site, temporally and spatially stable geochemical conditions are essential. Adjacent aquifers can induce changes into the system. It is therefore essential to investigate if and how the geochemistry and mineralogy of the sediments is influenced by the hydrogeology. Changes in the Opalinus Clay and the surrounding formations provide information about geochemical processes in the past and thus enable an assessment for the future.In this context, a 58 m long borehole was drilled at the Swiss Rock Laboratory in Mont Terri. Drilling was conducted from the Opalinus Clay (Toarcian) through the entire Staffelegg Formation (Toarcian-Sinemurian), which contains two water-bearing sections. The groundwater, the members and their transitions were characterised with a variety of analytical methods.Groundwater was found locally in the Beggingen (Gryphaea Limestone) and Rietheim (Posidonia Shale) members, depending on the presence of pathways in open fractures and with differences in their chemical composition. The groundwater in the Rietheim member is not directly connected to the surface, but seems to be continuously recharged by an adjacent aquifer. At the transition from the Gross Wolf to the Rietheim Member, pyrite increases and many trace elements are enriched. The Fe/Al paleoredox proxy and the enrichment of trace-metals like uranium reveal prevailing anoxic conditions in the sediment and groundwater. This is more indicative for a depositional than a mobilization feature. The influence of the groundwater can therefore be classified as limited due to its reducing conditions at this transition.The aim is to establish a method for analytically distinguishing between features of deposition, diagenesis, alteration and mobilization. This will allow assessment of the long-term integrity of the Opalinus Clay as a host rock and the surrounding formations. The gained understanding of the hydrogeological influence on the geochemical conditions within a system is to be transferred to other potential repository sites.
Railways on Permafrost: Unique Challenges Observed at Bridge Crossings along the Hudson Bay Railway
Authors: Arpin Natalie , Take Andy , Beddoe Ryley
Published: March 2024

The Hudson Bay Railway (HBR) serves as the singular land pathway connecting the Pas to Churchill, Manitoba, Canada. Hence, it is an essential means of transportation for northern communities, enabling the transport of both goods and individuals. However, it has faced many operational challenges because of its remote geographical location and the permafrost conditions it passes over. Over its 1000-kilometre length, the permafrost conditions transition. The railway starts in the isolated permafrost zone in its most southern portions before passing over discontinuous permafrost and then reaching continuous permafrost in its northern section. One of the unique operational challenges present at bridge crossings is the phenomena of “frost jacking”.Frost jacking refers to the upward displacement of pile bridge foundations caused by forces generated from frost heave in the surrounding ground. If the driving force from frost heave exceeds the frictional resisting forces anchoring a pile into the ground, uplift occurs. When designing pile foundations in cold regions, the potential effects of frost jacking must be considered, as any significant differential heave between piers or the abutments can lead to track geometry issues that affect operations and, in extreme cases, require bridge maintenance. However, research on frost jacking experienced by operational infrastructure has been very limited, which hinders the ability to account for its impacts.The Horn Creek Crossing on the Hudson Bay Railway is a 30-metre-long, steel ballast deck bridge supported by H-piles. Over a 10-year period, the foundations of the bridge underwent hundreds of millimetres of differential heave before repairs were completed to level the structure in July 2022. Because of the bridge’s remote location, there is limited information on the rate and timing of when frost jacking occurred. Therefore, in 2022, a multi-sensor monitoring program was designed and subsequently installed on the bridge with the purpose of collecting data to explore the mechanism of frost jacking at this site.Preliminary results from the first monitored winter season resulted in an average upward movement of 33 mm of the spans surrounding the northern pier. This upward movement occurred throughout the winter and ended when daily average temperatures became above 0°C. Afterwards, limited recovery was present in the spring when temperatures rose and was measured to be 11 mm, less than the upward movement measured. The monitoring process is still ongoing, with the aim of identifying longer-term trends and analyzing the outcomes of the repair work. Furthermore, using this site as the location of known differential heave at a railway bridge, methods are being developed to explore whether a parallel data source (track geometry data) can capture patterns and rates of seasonal differential heave at this and other bridges along the HBR.
Redox dependent sulfur partitioning between liquid and vapor: implications for magmatic-hydrothermal ore genesis and volcanic degassing
Authors: Zajacz Zoltan , Farsang Stefan
Published: March 2024

Magmatic-hydrothermal ore deposits form in response to metal precipitation from fluids released from crustal magma reservoirs. Following release from the magma, these fluids often go through phase separation involving the condensation of a saline liquid phase (=brine). The brine tends to stay in the deeper part of the hydrothermal system, whereas the vapor ascends to form epithermal ore deposits. Therefore, chemical contrast between these two phases may be deterministic for the spatial distribution of mineralization in magmatic-hydrothermal systems, and also affects volcanic sulfur outputs during quiescent periods. As sulfur is a key constituent for ore metal transport and precipitation, understanding its partitioning between the vapor and brine phases is critically important.We conducted experiments to determine the effect of oxygen fugacity on the partitioning of sulfur between vapor and brine at P-T conditions relevant for the magmatic-hydrothermal transition by trapping coexisting vapor and brine phases as synthetic fluid inclusions in quartz and subsequently analyzing them for sulfur concentrations by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The results show that at relatively low fO2 at which sulfur is predominantly present in 2- oxidation state, sulfur shows strong preference for the vapor phase with liquid/vapor partition coefficients around 0.2 at a liquid/vapor salinity contrast above a factor of 6. However, with increasing fO2, sulfur partitioning into the liquid phase increases corresponding to the transition of the redox state of sulfur from 2- to 4+ and 6+. In relatively alkaline fluids at the fO2 of the MnO-Mn3O4 buffer, the preferential partitioning of sulfur to the liquid phase is nearly as strong as that of NaCl. Liquid condensation from SO2-rich single-phase aqueous fluid at T = 875oC and P = 200 MPa were observed by in situ Raman spectroscopic experiments and sulfate was identified as the dominant sulfur species in the condensed liquid. It is thus apparent that liquid condensation in oxidized magmatic hydrothermal systems is a redox process that yields sulfate-bearing brines.A consequence of the above observations is that brines in typical porphyry Cu (-Au) ore forming systems will have the capacity to precipitate ore metal sulfides without externally derived sulfur, provided that some sulfate can be reduced to sulfide and the HCl produced during metal sulfide precipitation is consumed via fluid-rock interaction or is carried away by the vapor phase to higher levels of the system. In addition, a large fraction of the sulfur budget of the primary magmatic volatile phase in oxidized active arc volcanic systems may be stripped by brine condensation during quiescent degassing periods and may never reach the Earth’s atmosphere.
Airborne flux measurements for validation of VOC emission inventories and source attribution
Authors: Pfannerstill Eva Y. , Arata Caleb , Zhu Qindan , Schulze Benjamin C. , Woods Roy , Harkins Colin , Schwantes Rebecca H. , McDonald Brian C. , Seinfeld John H. , Bucholtz Anthony , Cohen Ronald C. , Goldstein Allen H.
Published: March 2024

For accurate prediction and modelling of air quality and climate, it is necessary to understand the emissions of volatile organic compounds (VOCs) from the potpourri of sources that they are emitted from: traffic, industry, households, plants, agriculture, etc. In the past, efforts to understand the magnitude and composition of VOC emissions have often relied on indirect methods – either using bottom-up emission models, or inferring emissions top-down from concentration measurements via chemical transport models. Both approaches rely on a number of assumptions regarding chemical reactions and transport - and thus are subject to large uncertainties.Airborne flux observations provide direct emission and deposition information at landscape scale with a resolution of a few km. We performed airborne eddy covariance measurements of a large range of VOCs on board a Twin Otter aircraft in Los Angeles and the agricultural San Joaquin Valley in California using PTR-ToF-MS. Combining these observations with a footprint model, we matched them with gridded inventories in space and time. The comparison with the inventories showed a good representation of typical traffic VOCs, but a significant underestimation of oxygenated VOCs (likely from volatile chemical products and cooking) and terpenoids by the inventories.Using airborne flux footprints in combination with landcover information of the San Joaquin Valley, we disaggregated the observed VOC emissions by multivariate linear regression and attributed them to their sources. This way, we obtained typical VOC emission rates and composition for dairy farms, citrus crops, citrus processing facilities, oak forests, oil and gas wells, and urban areas.
Aeolian saltation: median height, mean grain size, and dimensionless shear velocity
Authors: Zhang Pei , Bae Jinsu , Parteli Eric , Ellis Jean , Farrell Eugene , Li Bailiang , Sherman Douglas
Published: March 2024

We present field data demonstrating relationships associated with the development of aeolian mass flux profiles. Trajectories of saltating grains increase in height and length as their coefficient of restitution increases, thus do median saltation heights, hs50. The coefficient depends, in part, on the momentum of a saltating grain relative to the inertia of the bed material that it impinges upon. This manifests in the smaller grains in a population bouncing higher off of a given surface than the coarser grains in that same population, as first described by Bagnold (1937), and more recently by Dong et al. (2004) and Namikas (2006), among others. More controversial has been the relationship between median saltation height and shear velocity, u*, with some arguing that hs50 increases with u* (e.g., Bagnold, 1941; Owen, 1964; Willetts and Rice, 1985; Rice et al., 1995; Dong et al., 2012). Field investigations, however, have shown that hs50 is insensitive to u* (e.g., Creyssels et al., 2009; Ho et al., 2012; Martin and Kok, 2017; Delorme et al., 2023). These, and related studies, motivate this research.Measurements were made at three sites in the Mojave/Sonoran Deserts of Southern California (CA sites) and three sites in the Jericoacoara National Park in Ceará, Brazil (BR sites). Sites were chosen to represent a range of grain sizes. At each site, the data-gathering protocols were similar. Flux profile data were obtained using vertical stacks of mesh traps, grain size statistics were obtained from the trapped sand, and shear velocities were estimated using 3-D ultrasonic anemometer measurements. Mean grain sizes, d50, at CA1, CA2, and CA3 were 0.17, 0.18, and 0.16 mm. The respective values at BR1, BR2, and BR3 were 0.22, 0.39, and 0.39 mm. A total of 63 flux profiles and related data were evaluated.Regression analysis was used to test for a dependence of hs50 on a dimensionless shear velocity (u* /u*t, where the latter is the threshold shear velocity, estimated with d50) and indicated a strong, inverse relationship (R2 = 62%, P < 0.0001). When hs50 is normalized by dividing by d50, and the regression repeated, a statistically significant relationship was found. Finally, we tested for a relationship between the simple variables of median saltation height and mean grain size, finding that hs50 increases with d50 (R2 = 53%, P < 0.0001). In summary, median saltation height is not dependent on shear velocity but does depend on mean grain size.
Transient and lagged effects of vegetation dynamics on the global CO2 growth rate
Authors: Yang Hui , Santoro Maurizio , Luijkx Ingrid , Ciais Philippe , Wang Siyuan , Reichstein Markus , Besnard Simon , Carvalhais Nuno
Published: March 2024

The land carbon cycle is fundamental in regulating atmospheric CO2 dynamics from seasonal to centennial scales. The fine equilibrium between photosynthetic gains spent in metabolic costs and/or lost in mortality underpins the contribution of terrestrial ecosystems to the global carbon cycle. Uncertainties and divergent hypotheses on the role of climate in regulating their underlying mechanisms hamper our current diagnostic and prognostic abilities despite growing evidence on ecosystem vulnerability to present and future changes in climate. However, quantitative knowledge of the contributions of different carbon cycle processes regulating carbon uptake and release still need to be improved, inflating the uncertainties in future projections of net land-atmosphere carbon exchanges. In this study, we rely on satellite-based Earth observation retrievals of above-ground biomass and vegetation primary productivity to reconstruct the land-atmosphere carbon exchange dynamics over the last two decades, through the application of a three-box model at the pixel level. Our approach confidently reproduces 60% of the observed variability in atmospheric CO2 growth rate (CGR) over throughout 1997-2019 (R = 0.78, p-val < 0.05), with a low RMSE of 1.0 PgC yr-1. We further detail CO2 release from vegetation dynamics emerging from quick turnover induced by wildfires and leaves senescence, as well as the slow turnover from plant and soil decomposition mechanisms. This allows us to differentiate between transient and lagged effects on land-to-atmosphere fluxes. The carbon release, characterized by a lag of over one year, referred to as lagged effects. Globally, the lagged responses accounted for 50% of the variability in CGR, exceeding three times the contribution of transient fluxes from live vegetation. We have yet to a change or trend in the total contributions of vegetation dynamics to CGR. Yet, the relative role of lagged effects to CGR via decomposition fluxes increased by 50%, possibly due to accelerated mortality and decomposition fluxes. As global warming imposes higher stress on vegetation while increasing temperature-mediated decomposition, our results highlight the importance of quantifying their underlying metabolic responses. Such understanding is instrumental for assessing the contribution of adaptation and mitigation measures that will shape the contribution of the terrestrial carbon cycle to dampen the effects of anthropogenic emissions on global climate.
Unifying and comparing different models of viscous anisotropy to be included in ice sheet models.
Authors: Richards Daniel , Mantelli Elisa , Pegler Samuel , Piazolo Sandra
Published: March 2024

Ice fabrics – the alignment of crystal orientations - can cause the ice viscosity to vary by an order of magnitude, consequently having a strong impact on the large-scale flow of ice sheets and glaciers. Because of this, there is a need for fabric models which are computationally efficient enough to be included in large-scale ice sheet models. We examine a range of existing models in this class and show they can be combined into a common equation which is a function of 2-3 parameters. By comparing with observations from the Greenland ice sheet, we get the best model predictions by assuming the ice deforms close to the Sachs hypothesis – that all grains experience the same stress. As these fabric predictions also depend on the flow law used, we provide a test of competing anisotropic flow laws for the first time, making a step towards reliably incorporating the effect of fabric and viscous anisotropy in ice sheet flow models.
Scaling properties of irreversibility indices in turbulence
Authors: Schmitt François G.
Published: March 2024

In 3D turbulence there is a flux of energy from large to small scales in the inertial range, associated with irreversibility, i.e. a breaking of the time reversal symmetry (Pumir, 2016). Such turbulent flows are characterized by scaling properties and we consider here how irreversibility depends on the scale. Two indicators of irreversibility for time series are tested involving triple correlations in a non-symmetric way. The first one proposed by Pomeau (1982, 2004) is: Po(r)=-, where r is an increment and X(t) is the turbulent velocity which is stationary with zero mean. The second indicator has been proposed in the finance literature (Ramsey and Rothman, 1996), and was called symmetric bicovariance function: γ(r) = -. For time reversible processes, both indicators are zero, whereas their departure from 0 is an indicator of irreversibility.We study these indicators applied to fully developed turbulence time series, from flume tank, wind tunnel and atmospheric turbulence databases. It is found that irreversibility occurs in the inertial range and has scaling properties with slopes close to one. A maximum value is found around the injection scale. This confirms that the irreversibility is associated with the turbulent cascade in the inertial range and shows that the irreversibility is maximal at the injection scale, the largest scale of the turbulent cascade.This is published in Schmitt, F.G., Scaling analysis of time-reversal asymmetries in fully developed turbulence, Fractal and Fractional, 7(8), 630, 2023.  https://doi.org/10.3390/fractalfract7080630Cited references: Pumir et al., Phys. Rev. Lett.. 116, 124502 (2016); Pomeau, J. de Physique 43, 859 (1982); Pomeau, Lect. Notes Phys. 644, 425 (2004); Ramsey and Rothman, J. Money Credit Bank. 28, 1 (1996).
An Improved Representation of The Variable Contributing Area Concept in Hydrologic and Land Surface Models
Authors: Stadnyk Tricia , Ahmed Mohamed Ismaiel , Clark Martyn , Pietroniro Alain
Published: March 2024

Hydrologic modelling in the low-lying, flat prairie or arctic pothole regions is challenging because of variable contributing areas that modify the transformation of local runoff into streamflow. Most hydrological and land surface models fail in predicting prairie hydrology due to overlooking or inadequately representing the variable contributing area dynamics. In this study, we develop an open-source, model-agnostic version of a revised formulation of the recently developed Hysteretic Depressional Storage (HDS) model. This revised formulation accounts for the hysteretic relationship of pothole depressions and its effects on streamflow generation. The revised HDS model is implemented and tested with two different hydrological models of varying complexity (MESH and HYPE). The modified hydrological models are tested on a number of prairie pothole basins in Canada. Results show improved simulations of the streamflow response in the tested basins. Importantly, the modified models replicate the known hysteretic relationships between depressional storage and contributing areas in that region. The open-source HDS implementation approach is designed for use in hydrologic or land surface modelling systems, enabling improvements in simulating the complex hydrology and streamflow regimes globally.
Modelling the functionally diverse Caatinga: insights into a unique tropical forest
Authors: Sabot Manon , Nobrega Rodolfo , Moura Magna , De Kauwe Martin , Majcher Bartosz , Cosme Luiza , Miatto Raquel , Ferreira Domingues Tomas , Pitman Andy , Prentice Iain Colin , Verhoef Anne
Published: March 2024

From heightened canopy dieback to tree die-off, many forest ecosystems are showing signs of poorly coping with more severe, more frequent, or hotter droughts. Understanding forest resilience to drought has become paramount, and eco‐physiological optimisation approaches that test behavioural hypotheses have been proposed as a means to build this understanding in global terrestrial models. Here, we used a land-surface model that considers competing optimality principles to simulate canopy gas exchange and leaf nitrogen investments into the photosynthetic apparatus, whilst also accounting for sustained hydraulic impairment (Sabot et al., 2022). We applied this model to a pristine observational site of the Caatinga, Brazil’s drought-hardy, seasonally deciduous, and exceptionally diverse dry tropical forest. Six woody species dominate 80% of the study area whilst displaying contrasting functional strategies – for example, their respective P50s (the water potential at which 50% of a plant’s hydraulic conductivity is lost) range between -1 MPa and -5 MPa. Model predictions were assessed against species-specific leaf-level observations of stomatal conductance and photosynthetic uptake, as well as eddy covariance measurements of ecosystem carbon and water fluxes spanning a period with high interannual rainfall variability (and including a severe multi-year regional drought). We found that none of the six species could, in isolation, explain the magnitude and dynamics of the observed surface fluxes. However, taken together and accounting for their relative contribution to total ecosystem fluxes, they did. Further, our analysis emphasises the vital role of phenology in mitigating seasonal and inter-annual hydraulic risks, with foliage reductions triggered by a 10 to 20% loss of hydraulic conductivity in the canopy. On the whole, accounting for diverging species-level responses and their relative influence at the ecosystem-scale appears key to improving model predictions in functional diverse forests. Reference: Sabot, M.E.B., De Kauwe, M.G., Pitman, A.J., Ellsworth, D.S., Medlyn, B.E., Caldararu, S. et al. (2022) Predicting resilience through the lens of competing adjustments to vegetation function. Plant, Cell & Environment, 45, 2744–2761.
Modeling inherited structures and their effects on strain localization during continental rifting 
Authors: Moucha Robert , Xue Liang
Published: March 2024

Continental rifting is a fundamental process of plate tectonics and the Wilson Cycle where weak zones within the continental lithosphere are exploited by both far-field and near-field forces to break-up the continental lithosphere (e.g Molnar et al., 2019). These pre-existing weak-zones are remnants of past tectonic deformation, delineated by shear zones, faults, and/or mobile belts. Reactivation of such inherited structures from previous tectonic phases has been attributed to several continental rift systems, for example, the Rhine graben, Rio Grande rift, Main Ethiopian Rift, Malawi Rift, and the Red Sea. In geodynamic modeling of continental rifts, these weak zones are often approximated by lithospheric thermal perturbation or a weak seed/fault to facilitate strain localization and initiate rifting in response to uniform stretching of the lithosphere. Here, we adopt a different approach building upon models by Salazar-Mora and Sacek (2022) and Peron-Pinvidic et al. (2022) to implement the inherited structures. We start with a geodynamic simulation of continental collision and orogenesis prior to extension but include the effect of temperature-dependent strain healing in the mantle (e.g. Fuchs and Becker, 2021) and time dependent plastic strain healing in the crust (e.g. Olive et al., 2016). We use a 2D geodynamic model ThermoMech (e.g. Xue et al., 2023) coupled to a landscape evolution model FastScape (Yuan et al., 2019), to explore the parameter space in an effort to understand the longevity of weak zones and their implications for rift initiation. Fuchs, L. & Becker, T. W. (2021). Deformation Memory in the Lithosphere: A Comparison of Damage-dependent Weakening and Grain‐Size Sensitive Rheologies. J. Geophys. Res.: Solid Earth 126.Molnar, N. E., Cruden, A. R., & Betts, P. G. (2019). Interactions between propagating rifts and linear weaknesses in the lower crust. Geosphere, 15(5), 1617–1640.Olive, J.-A., Behn, M. D., Mittelstaedt, E., Ito, G. & Klein, B. Z. (2016). The role of elasticity in simulating long-term tectonic extension. Geophys. J. Int. 205, 728–743.Peron-Pinvidic, G., Fourel, L. & Buiter, S. J. H.  (2022). The influence of orogenic collision inheritance on rifted margin architecture: Insights from comparing numerical experiments to the Mid-Norwegian margin. Tectonophysics 828, 229273.Salazar-Mora, C. A. & Sacek, V. (2023). Effects of Tectonic Quiescence Between Orogeny and Rifting. Tectonics 42.Xue, L., Muirhead, J. D., Moucha, R., Wright, L. J. M. & Scholz, C. A. (2023). The Impact of Climate-Driven Lake Level Changes on Mantle Melting in Continental Rifts. Geophys. Res. Lett. 50.Yuan, X. P., Braun, J., Guerit, L., Rouby, D., & Cordonnier, G. (2019). A New Efficient Method to Solve the Stream Power Law Model Taking Into Account Sediment Deposition. J. Geophys. Res.: Earth Surface, 124(6), 1346–1365.
Spatial Distribution of Mixing and Transport in the Northern Middle Atmosphere
Authors: Curbelo Jezabel , Mechoso Carlos R.
Published: March 2024

We apply a novel approach to studying eddy mixing and transport in the northern middle atmosphere during winter (December-January-February), based on the concept of Lagrangian diffusivity – a measure of how quickly air parcels mix together. Unlike traditional diagnostics that rely on longitudinal or contour-based averages, Lagrangian diffusivity provides a detailed three-dimensional view of the mixing process. Our formulation of Lagrangian diffusivity requires the calculation of parcel trajectories, performed on isentropic surfaces using ERA5 reanalysis data. Additionally, we have applied several diagnostic techniques to contextualize our results on Lagrangian diffusivity within the broader framework of the stratospheric polar vortex and quasi-geostrophic wave properties. Specifically, we investigate the influence of quasi-geostrophic motions on the stratospheric polar vortex using wave activity flux and local wave activity. Furthermore, we employ a Lagrangian descriptor, a tool based on parcel trajectory length, to locate the boundary of the stratospheric polar vortex (SPV).The results reveal pronounced zonal asymmetries in Lagrangian diffusivity and wave activity flux. Mixing is highest at mid-latitudes around the prime meridian and at locations within the SPV. Local wave activity is elevated at high latitudes and upstream of the climatological vortex boundary opening, highlighting the role of quasi-geostrophic waves in the southward displacement of mid-latitude westerlies.
A purely spaceborne approach for nearshore bathymetry monitoring
Authors: Thomas Nathan , Campbell Anthony , Lee Brian , Bunting Pete , Grossman Sofia , Fatoyinbo Lola
Published: March 2024

Nearshore bathymetric monitoring is critical for understanding and quantifying the blue economy, yet in-situ surveys are costly and time-consuming. While remote sensing has been able to overcome some of these limitatons, a purely spaceborne approach has so far not been achievable. Here, we provide a method for combining spaceborne optical imagery and ICESat-2 spaceborne lidar to generate an end-to-end method of nearshore bathymetric modeling. Discrete benthic depths are extracted from ICESat-2 data using custom open source software (C-SHELPh) and combined with optical imagery using Machine Learning algorithmsto create spatially continuous bathymetric models for a range of study sites distributed globally. We demonstarte an ability to generate national scale bathymetric models at high spatial resolution (2 - 30 m) and with low error (6%), outperforming existing interpolated multi-year surveys and providing new information in data scarce areas. In addition, our methods are readily repeatable, enabling time-series change detection and monitoring. Our open source approach provides both the research and applications communities with methods and products for modeling and monitoring nearshore coastal sub-aquatic structure, providing new transformative data to understudied portions of our oceans.
Zircon U-Pb ages and Lu-Hf isotopes of Paleoproterozoic metasedimentary rocks in the North China Craton: Implications for its crust and evolution
Authors: Chen Nancy Hui-Chun
Published: March 2024

The northern margin of the North China Craton is an important tectonic zone, bordered by the globe’s largest Phanerozoic accretionary orogen, the Central Asian Orogenic Belt. The Paleoproterozoic strata on the northern margin of the North China Craton (NCC) comprise a relatively intact low-grade (meta-)sedimentary sequence, but whether there are breaks in the sequence and the tectonic setting in which the sequence was deposited are uncertain. In this work, Lu–Hf isotopic, and zircon U–Pb geochronological analyses were performed on (meta-)sedimentary rocks from the Paleoproterozoic strata, to investigate the potential provenance, depositional age, and depositional environment, and discuss the likely tectonic setting of sedimentation on the northern margin of the NCC during the Paleoproterozoic. The distribution of detrital zircon ages shows that the lower meta-feldspathic sandstone unit of the Paleoproterozoic sequence was deposited after ca. 2.2 Ga, whereas the maximum depositional age of (meta-)quartz siltstone and quartzites were around 1.89 Ga and at from ca. 1.86 to 1.81 Ga, respectively. Integration of our U–Pb and Hf isotope data with data from the other regions of the NCC, indicate that the Paleoproterozoic strata have experienced a depositional environment between ca. 2.2–1.81 Ga in an extensional basin system. We further proposed that the northern margin of the NCC evolved from an extensional tectonic setting, possibly related to slab rollback. Subsequently, the Paleoproterozoic sequence was affected by a ~1.8 Ga metamorphic event to form these (meta-)sedimentary rocks in the region.
Seismicity in the Bransfield Strait, Antarctica, using temporal Ocean Bottom Seismographs data
Authors: Jung Jinhoon , Park Yongcheol , Lee Won Sang , Park Seewon
Published: March 2024

The Bransfield Basin, located between the South Shetland Island and the Antarctic Peninsula in Western Antarctica, is formed by slab rollback of the South Shetland Trench and complementary extensional. The region also has large and small active volcanoes like the Orca volcano. Various earthquakes have occurred due to tectonic movement and volcanic activities. Since the Mw 4.9 earthquake struck at a depth of 10 km in the vicinity of South Shetland Islands on 29 August 2020 (USGS), moderate earthquakes have constantly been reported adjacent to Bransfield Basin like an earthquake swarm.The Extreme Geoscience Team (EGG) at the Korea Polar Research Institute (KOPRI) has been operating a seismic station at the King Sejong station. Other countries have been running their seismic stations in the South Shetland Islands, such as the Antarctic Seismographic Argentinean Italian Network (ASAIN) and Chilean seismic stations, to monitor local earthquakes associated with back-arc spreading and submarine volcanic activities in this area. However, these seismic stations are located on the islands, and the inter-station distance is over 50 km. To make up for the poor coverage of seismic stations, we installed 5 OBSs in the earthquake swarm area between 2020 and 2021.Using cross-correlation with onland seismic data and OBSs data, we conducted the template matching analysis and detected 67,952 events from August 29, 2020, to December 31, 2021. We relocated 2,313 epicenters of the seismic events by manually picking the first arrival of the P-wave. We found that the earthquake swarm’s epicenters were mainly concentrated in the central basin of the Bransfield Strait.We categorize the characteristics of the earthquake near Bransfield Basin. We will contribute to understanding the dynamics and evolution of subduction zones in Bransfield Basin. 
Hydration structure on dolomite: Telling calcium and magnesium apart
Authors: Kühnle Angelika
Published: March 2024

The hydration structure at the mineral-water interface is decisive for understanding fundamental reactions taking place at mineral surfaces, including mineral dissolution, growth and weathering. Recent advancements in three-dimensional atomic force microscopy (3D AFM) have opened the potential to directly image the hydration structure above a surface, providing unparalleled structural insights into mineral−water interfaces [1].Here, the hydration structures at the calcite-water [2] and dolomite-water [3] interface will be presented with an emphasis on discussing the differences that arise from the presence of magnesium in dolomite as compared to calcium in calcite. Analysing site-specific vertical positions of hydration layers and comparing them with molecular dynamics simulations unambiguously unravels the minute but decisive difference in ion hydration and provides a clear means for telling calcium and magnesium ions apart. [1]         T. Fukuma, Y. Ueda, S. Yoshioka, H. Asakawa, Phys. Rev. Lett. 2010, 104, 016101[2]         H. Söngen, M. Nalbach, H. Adam, A. Kühnle, Rev. Sci. Instrum. 2016, 87, 063704[3]         H. Söngen, C. Marutschke, P. Spijker, E. Holmgren, I. Hermes, R. Bechstein, S. Klassen, J. Tracey, A. S. Foster, A. Kühnle, Langmuir 2017, 33, 125
Changes in atmospheric dynamics over Dansgaard-Oeschger climate oscillations around 40 ka and its impact on Europe
Authors: Stadelmaier Kim Helen , Ludwig Patrick , Pinto Joaquim G. , Újvári Gábor
Published: March 2024

Dansgaard-Oeschger (D-O) climate variability during the last glaciation was first evidenced in ice cores and marine sediments, and is also recorded in various terrestrial paleoclimate archives in Europe. The relative synchronicity across Greenland, the North Atlantic and Europe implies a tight and fast coupling between those regions, most probably effectuated by an atmospheric transmission mechanism. In this study, we investigated the atmospheric changes during Greenland interstadial (GI) and stadial (GS) phases based on regional climate model simulations using two specific periods, GI-10 and GS-9 both around 40 ka, as boundary conditions. Our simulations accurately capture the changes in temperature and precipitation as reconstructed by the available proxy data. Moreover, the simulations depict an intensified and southward shifted eddy-driven jet during the stadial period. Ultimately, this affects the near-surface circulation towards more southwesterly and cyclonic flow in western Europe during the stadial period, explaining much of the seasonal climate variability recorded by the proxy data, including oxygen isotopes, at the considered proxy sites.
Zooplankton and Micronekton products from the Copernicus Marine Service catalogue: state of the current product and development plan
Authors: Titaud Olivier , Conchon Anna , Mérillet Laurène , Albernhe Sarah , Magliano Héloïse
Published: March 2024

Since mid-2019, meso-zooplankton and micronekton reanalyses (large past time series that are processed with time-consistent forcings) are available and regularly extended for the Copernicus Marine Service catalogue. The product (also known as MICRORYS) is computed using SEAPODYM-LMTL, the Lower and Mid Trophic levels model of the Spatial Ecosystem And POpulation DYnamic Modeling framework. Meso-zooplankton organisms (200µm-2mm) constitute the low-trophic level. These organisms are transported along with the water masses. Micronekton organisms, constituting the mid-trophic level, are bigger organisms (2-20cm) able to swim over short distances. SEAPODYM models the spatial and population dynamics of the LMTL population with a system of advection-diffusion-reaction equations. The vertical dimension is simplified into three layers (namely epipelagic, upper, and lower mesopelagic). Layers matches the vertical distribution of organisms that is observed. The six micronekton groups are defined according to their diel vertical migration from the surface at night to the deep ocean during the day. Now MICRORYS products use a global configuration of SEAPODYM at 1/12° daily resolution. This product has evolved considerably since the first delivery. We propose here to review the state of the art of this product. Some case studies and the developments that are expected soon, especially those concerning a new computational grid that bypasses the problem at the poles will be presented.
Soil Structural Stability Influenced by Land Management
Authors: Mikha Maysoon , Green Timothy , Untiedt Tyler , Hergret Gary
Published: March 2024

Soil structure is an important factor in regulating soil ecological functions and soil chemical, physical, and biological properties. This study evaluated soil structural stability from three locations within the central Great Plains (USA) under different management practices.  The study sites consisted of Alternative Crop Rotation (ACR) and Long-Term Tillage (LTT) near Akron, Colorado, and Knorr-Holden (KH) near Mitchell, Nebraska.  Tillage treatments consisted of no-tillage (NT), reduced tillage (RT), conventional tillage (CT), and moldboard plow (MP). Commercial mineral fertilizer (F) was used as a nitrogen source in ACR and LTT sites while manure (M) plus F treatments were used in KH.  Soil structural stability was evaluated using four indices, aggregate stability index (ASI), mean weight diameter (MWD), geometric mean diameter (GMD), and fractal dimension (FD).  At 0-15 cm depth, intensive tillage (CT and MP) in ACR and LTT, reduced (P < 0.05) ASI by 46.7%, MWD by 21.0% and GMD by 8.4% and increased FD by 0.77% compared with NT and RT treatments.  The addition of manure increased (P < 0.05) ASI by 72.2%, MWD by 65.6%, GMD by 32.8%, and reduced FD by 5.5% compared with tillage treatments in ACR and LTT.  Although FD was negatively correlated with MWD and GWD; it provides information not captured by ASI and complements MWD and GWD.  The indices presented in this study, including FD, are effective in measuring soil structural stability and should be considered further in management decisions to sustain soil resources and enhance economic returns.
Contraction of the radius of maximum symmetric rotational kinetic energy during the intensification of Tropical Cyclone Khanun (2017)
Authors: Shi Yishe , Li Xiaofan
Published: March 2024

Tropical cyclone (TC) Khanun in 2017 was simulated in this study by the Weather Research and Forecasting (WRF) model. The observation-validated simulation data were used to examine dominant dynamic processes resulting in the contraction of the radius of maximum kinetic energy of symmetric rotational flow. The contraction rate was quantified by calculating the radial derivatives of symmetric rotational kinetic energy budget. The radius of maximum symmetric rotational energy was contracted rapidly before rapid intensification (RI) and moved inward slowly, then barely moved, and moved inward slowly again during RI.The conversion from kinetic energy of asymmetric rotational flow to symmetric rotational flow induced by advection of asymmetric rotational tangential wind by asymmetric divergent radial wind at dominant azimuthal wavenumber-1 asymmetry and convergence of inward flux of symmetric rotational flow led to the rapid contraction before RI. During RI, symmetric rotational energy grew in the lower troposphere significantly, and upward flux convergence was equally important as inward flux convergence of symmetric rotational flow, which caused the first slow contraction. The conversion from kinetic energy of symmetric divergent wind to symmetric rotational flow associated with co-locations of maximum symmetric rotational energy and maximum symmetric inward radial flow produced stationary maximum symmetric rotational energy. Finally, horizontal and vertical flux convergence of symmetric rotational flow, and the conversion from environmental kinetic energy to symmetric rotational kinetic energy through the interaction between symmetric rotational flow and symmetric radial environmental flow generated the second slow contraction.
Be-derived catchment-wide erosion rates from the Nock Mountains (Gurktal Alps, Austria): comparison with thermochronological data and implications for landscape evolution
Authors: Hampel Andrea , Wölfler Andreas , Wolff Reinhard , Hetzel Ralf
Published: March 2024

In contrast to the mountainous topography and high relief of the eastern Tauern window, the adjacent Nock Mountains (Gurktal Alps, Austria) are characterized by hilly topography, lower relief and rounded summits with elevations of ca. 2000 m. Although the unusual landforms in the Nock Mountains have long been recognized (Hejl, 1997; Frisch et al., 2000, and references therein), little is known about rates of landscape evolution in this area, which was deglaciated ~15 ka ago (Wölfler et al., 2022). Here we present a new set of 16 catchment-wide erosion rates from the Nock Mountains derived from cosmogenic 10Be concentrations in stream-sediment samples. Samples from 10 major streams that drain the Nock Mountains toward the Mur-Mürz valley, the Katschberg-Lieser valley and the Drau valley range between ~130 and ~300 mm/ka. Smaller subcatchments with low relief located in the upper part of the larger catchments erode at lower rates between ~80 and ~160 mm/ka. A comparison between 10Be-derived erosion rates and exhumation rates obtained from low-temperature thermochronology and thermokinematic modelling reveals that short-term and long-term erosion rates are remarkably similar. In the central Nock Mountains, 10Be-derived erosion rates of 110-160 mm/ka are similar to the long-term exhumation rate of ~160 m/Ma since ~34 Ma (Wölfler et al., 2023). The southern Nock Mountains (Millstatt Complex) show higher short-term erosion rates of 170-300 mm/ka and also a higher long-term exhumation rate of ~270 m/Ma since 18 Ma (Wölfler et al., 2023). The similarity between short-term and long-term erosion rates suggests that the pace of erosion in the Nock Mountains did not change significantly during the late Cenozoic. A comparison of our data with 10Be erosion rates from the eastern Tauern Window (>500 m/Ma) and the Lavanttal Alps (