bluuebunny/crossref_metadata_2025 huggingface dataset:
How do Natural Water Retention Measures modify connectivity on agricultural hillslopes?
Authors: Perez John Edward , Poeppl Ronald , Turnbull Laura , Tiwari Shubham , Wainwright John
Published: February 2023

Fine-sediment input into river networks presents one of the biggest environmental pressures in agricultural catchment systems due to accelerating soil erosion rates associated with agricultural practices. To understand and effectively manage this problem, it is essential to identify sediment source areas and the pattern of linkages between different landscape compartments along the sediment pathways that ultimately end up in the river channel. Sediment connectivity is an increasingly used concept to help assess both on-site and off-site impacts of soil erosion by describing the efficiency of fine-sediment transfer through these different zones. Natural Water Retention Measures (NWRM) that emulate natural processes to enhance or restore the water retention capacity of ecosystems, available to be applied at agricultural fields, can be understood within this framework as they modify connectivity and provide benefits that include erosion and sediment control. The aim of this study is to assess the differences in sediment connectivity associated with scenarios of different NWRM (e.g. buffer strips, strip cropping, terracing, mulching) in a selected hillslope of the Fugnitz Catchment (Austria). Using a process-based sediment-transport model (MAHLERAN; Wainwright et al., 2008), runoff and sediment transport were dynamically simulated. Simulation results of water and sediment fluxes were then translated into a graph representing the flow network, consisting of nodes and edges, where connectivity and network properties can be quantified using graph-theoretical metrics (e.g. betweenness centrality). The same workflow was used for other NWRM scenarios, modifying parameters of the sediment transport model to capture the NWRM conditions. The results show notable changes in connectivity between scenarios as well as varying patterns of hot spots where sediment delivery is high and where interventions may be targeted, thus providing options of agricultural practices that can be implemented to improve sustainability in agricultural catchments.
Water user Fab Labs: co-design of low-tech sensors for irrigated systems
Authors: Vandôme Paul , Leauthaud Crystele , Moinard Simon , Mekki Insaf , Zairi Abdelaziz , Belaud Gilles
Published: February 2023

Mediterranean agriculture is facing the challenge to produce sustainably with a water resource under pressure. As irrigated areas expand in response to increasing vulnerability to drought, it is essential to support water users towards better agricultural water management. We set up two Fab Labs on the shores of the Mediterranean (France and Tunisia) to bring together water users around a collective project: co-constructing innovations to address local water management issues. A range of low-tech, low-cost and open source IoT-based sensors emerged from this process. The technologies were tested with users during the 2022 irrigation season. The aim of this study is to provide feedback on this participatory method as a facilitator for creating and sharing innovation in rural territories and to discuss the opportunities, benefits and limitations related to the use of these new technologies. We believe that this work contributes to make the measurement of water flows - and thus their understanding and better management - more accessible to the agricultural sector.     
Quantifying earthworm bioturbation from changes in vertical bulk density profiles
Authors: Larsbo Mats , Koestel Johannes , Krab Eveline , Klaminder Jonatan
Published: February 2023

The rate at which soil becomes physically mixed due to earthworm actions (bioturbation) has relevance for the fate of nutrients and pollutants and for the soil’s ability to sequester carbon. Nevertheless, methods to quantify bioturbation under field-like conditions are largely lacking. The soils of the Fennoscandian tundra offer a special possibility to quantify bioturbation, because they have developed in the absence of soil burrowing macrofauna. They commonly exhibit a thick organic layer on top of the mineral soil with a sharp layer boundary. The bulk density of the two soil layers differs markedly. Since bioturbation mixes both soil layers, the temporal changes in the bulk density profile of such soils may be exploited to estimate bioturbation rates in the field. In this study, we applied a model for earthworm bioturbation to observed changes in soil densities occurring in a mesocosm experiment with intact soil carried out in the arctic during four summers. We show that changes in soil density profiles can indeed be used to infer realistic earthworm bioturbation rates. Although uncertainties in parameter values were sometimes large, the results from this study suggest that soil turnover rates and endogeic earthworm soil ingestion rates in tundra soils may be as high as those reported for temperate conditions. Such large bioturbation rates can explain observed large morphological changes in nearby soils where dispersing earthworms have resulted in complete inmixing of the organic layer into the mineral soil. Our model is applicable to soil profiles with marked vertical differences in bulk density such as the soils of the Fennoscandian tundra where earthworms are currently dispersing into new areas and to layered repacked soil samples that are incubated in the field.
Inverse Modeling of the Initial Stage of the 1991 Pinatubo Volcanic Cloud Accounting for Radiative Feedback of Volcanic Ash
Authors: Ukhov Alexander , Stenchikov Georgiy , Osipov Sergey , Krotkov Nickolay , Gorkavyi Nick , Li Can , Dubovik Oleg , Lopatin Anton
Published: February 2023

The evolution of volcanic clouds is sensitive to the initial three-dimensional (3D) distributions of volcanic material, which are often unknown. Here, we conduct inverse modeling of the fresh Mt. Pinatubo cloud to estimate the time-dependent emissions profiles and initial 3D spatial distributions of volcanic ash and SO2. We account for aerosol radiative feedback and dynamic lofting of volcanic ash. It results in a lower (by 1 km for ash) injection height than that without ash radiative feedback. The solution captures the elevated ash layer between 14 and 24 km and the meridional height gradient during the first two days after an eruption. A significant fraction of the emissions (i.e., 6/16.6 Mt of  SO2 and 34/64.22 Mt of fine ash) did not reach the stratosphere. The results demonstrate that the Pinatubo eruption ejected ~78% of fine ash at 12 to 23 km, ~64% of  SO2 at 17 to 23 km, and most of the ash and  SO2 mass for the first two days after the eruption resides in the 15- to 22- km layer. 6 Mt of tropospheric  SO2 oxidized into sulfate aerosol within a week. This outcome might help to explain the discrepancies between the observations and model simulations recently discussed in the literature. The long-term evolution of the Pinatubo aerosol optical depth simulated using the obtained ash and  SO2 initial distributions converges with the available stratospheric aerosol and gas experiment (SAGE) observations a month after the eruption when the tropospheric aerosol cloud dissipated.
The role of biofilm as a bio-accumulator of Ultraviolet Filters in porous media
Authors: Rodriguez-Escales Paula , Jou Sonia , Carrera Jesus , Martinez Lurdes , Diaz-Cruz Silvia , Sunyer Adria , Quitana Gerard , Valhondo Cristina
Published: February 2023

Ultraviolet filters (UVFs) are contaminants of emerging concern (CECs) produced and used in large quantities worldwide. They are constituents of a large number of personal care and hygiene products and other consumer goods. Benzophenones, such as benzophenone-3 (BP-3), benzophenone-4 (BP-4) and avobenzone (AVO), are among the most used. These compounds are characterized by being photo-stable and lipophilic. Although it is highly known the lipophilicity of these compounds, their monitoring in porous media is centered in the aqueous phase. Nevertheless, their high logKow make foreseeable the accumulation in more lipophilic phases such as biofilm or sedimentary organic matter. For that, in this work we have highly characterized a Managed Aquifer Recharge system with a very intensive monitoring of benzophenones and transformation products in the three phases: water, biofilm and sedimentary organic matter. Furthermore, we have contrasted our results with a numerical model, which was based on the partition of UVFs under equilibrium conditions. Our results show that biofilm acted as an additional environmental compartment favoring the retention and degradation of UVFs in porous media. Indeed, it played a central role in the fate of these compounds, controlling both sorption and biodegradation. With this we believe that the current understanding of the organic compounds fate should incorporate it as a new compartment capable of bio-accumulate these compounds.
Calibration of coastal hydrogeological models for the analysis of groundwater-induced flooding: from instrumentation to model reliability
Authors: Le Mesnil Martin , de Dreuzy Jean-Raynald , Aquilina Luc , Gresselin Frédéric , Gauvain Alexandre
Published: February 2023

We determine the sensitivity of groundwater-induced flooding forecast to different modelling strategies (evolving model structure and quantity/nature of data). We test three calibration strategies on shallow coastal aquifers:we use the river network as a proxy of aquifer seepage and determine uniform hydraulic conductivity and porosity. Despite limiting assumptions of surface/groundwater connections, this strategy could be broadly deployed with rapid advances in temporal and spatial river mapping at regional to national scales.
we calibrate uniform conductivity and porosity on hourly piezometric data time-series close to the seashore, which are controlled by both tide and inland aquifer recharge fluctuations. We investigate the limitations of the uniform assumptions and demonstrate the interests of coastal and inland forcing as complementary sources of information.
we introduce spatially variable conductivities and porosities and use additional inland piezometers. Hydraulic parameters are mapped to the main geological structures of the studied area.
We analyse the results of these 3 competing strategies on the hydraulic parameters and, in a more prospective way, on the spatial distribution of vulnerabilities to groundwater fluctuations. We perform our analysis within the “Rivages Normands 2100” research project, in several sites of Western Normandy (France). In this area, low-lying coastal areas and neighbouring lands are prone to groundwater table increase, leading to flooding of buried networks and building foundations. The site of Saint-Germain-sur-Ay (66 km2 coastal watershed) is equipped with 6 piezometers from which we collected 1.5 year-long hourly time series of groundwater level. It includes a low-elevation coastal area made up of sands and a continental area made up of schists.  The modelling approaches allowed us to simulate groundwater levels up to 2100, and to analyse the associated evolution of vulnerability. Simulations are performed using Modflow on a daily timestep, with a 75 m spatial resolution.Results obtained from the 3 models consistently show that vulnerable areas are mostly clustered close to the shoreline. We also show that, in the studied watershed, the first calibration strategy using the river network data leads to long-term simulations close to the second calibration strategy using the piezometric data of the coastal area. Integration of extra piezometric data from the continental area in the third strategy provides more reliable simulations. This analysis is progressively deployed to other sites and extended to cost-benefit analyses including the costs of site instrumentation and the benefits of forecast reliability. Integration of flood zones aerial photography during extreme events is being implemented to the first modelling strategy, as well as wetland mapping.
Fighting Climate Misinformation: Fact-Checking of Climate Misinformation in Spanish-speaking podcasts.
Authors: Olano Pozo Jon Xavier , Cimolai Caterina , Arnal Andrea , Cisneros Bermejo Mercè , Boqué Ciurana Anna , Dermit Daniel , Massip Marc , Sigró Javier , Aguilar Enric
Published: February 2023

Despite the evidences of the effects of climate change, and the need to adopt adaptation and mitigation measures against its effects,  it still exists a significant current of denialism . Radio podcasts, an evolution of classical radio shows, are an interesting communication and leisure tool for disseminating climate misinformation in today's saturated communication world.In the framework of the CLIMACAST: UNDERSTANDING AND EXPOSING CLIMATE MISINFORMATION ON PODCASTS project, we monitor, identify, verify and disseminate short notes to fight this climate misinformation. Currently, the project is in the middle of its execution; and we have monitored monitoring more than a thousand hours of podcasts in Spanish-speaking countries from July to December of 2022. The project, funded by META and Poynter’s International Fact-Checking Network is a joint collaboration between C3/IU-RESCAT/URV, VERIFICAT and Kinzen and Chequeados.The climate misinformation measure unit of this project is a climate claim. A claim is the smallest unit of analysis of verifiable information containing a disputed claim about climate, climate variability and climate change. In addition, to be considered a claim, the information or meaning included in the message should be verifiable content. To track problematic terms, the editors of Verificat monitor podcasts where people post climate disinformation to detect recurring words or phrases in this area to define keywords to find the podcasts. When the podcasts are selected, an artificial intelligence tool transcribes them to a specifically designed dashboard. If it detects problematic content - for example, the word 'calentólogo' (warmist) is typical of negationist slang - the system highlights the keyword for greater detection by analysts. The analyst checks if the keyword refers to some climate and/or meteorological aspect. Then, the analyst determines the content's verifiability based on the message's real climate disinformation. Each claim identified is classified in six main narratives: the main misinformation: climate change does not exist, climate change is not human-caused, climate change is not bad, solutions to face climate change do not work, climate science is not liable and greenwashing.The results show how the claims are regularly identified in regular podcasts. However, it also shows slight growth in the two weeks of COP27.
The efficacy of high frequency petrological investigation at open-conduit volcanoes: The case of May 11 2019 explosions at southwestern and northeastern craters of Stromboli
Authors: Pontesilli Alessio , Del Bello Elisabetta , Scarlato Piergiorgio , Mollo Silvio , Ellis Ben , Andronico Daniele , Taddeucci Jacopo , Nazzari Manuela
Published: February 2023

Typically, petrological monitoring studies focus on comparing eruptive phenomena with textural and compositional features of eruptive products recovered over the long term (days to years). In this contribution we present a high spatial (individual eruptive centers) and high temporal (minutes to hours) resolution petrological and volcanological investigation using as test site Stromboli volcano. On May 11 2019, we had the rare opportunity to collect individual fresh fallout ash products from eighteen consecutive explosions, and at the same time, to acquire continuous high frequency (50 Hz) infrared thermal data. We observe that explosions were more frequent and ash-dominated at the southwestern crater area (SCA, 8–10 events/hour) than at the northeastern crater area (NCA, 3–5 events/hour), where coarser material was ejected. The statistical analysis of glass and plagioclase compositions reveals differences in the products erupted from the two crater areas. SCA explosions tapped less differentiated magmas in equilibrium with more anorthitic plagioclase cores (An~72–88), whereas NCA area explosions are more differentiated and in equilibrium with less anorthitic plagioclase cores (An~68–82). Thermometric calculations based on clinopyroxene-plagioclase-melt equilibria highlight that NCA eruptions were fed by a colder magma relative to that feeding SCA eruptions. Diffusion modeling of Li concentration profiles in plagioclase also indicates longer timescales of magma degassing and ascent for NCA eruptions, leading to preferential groundmass crystallization at the conduit walls and transition from sideromelane to tachylite textures. The final emerging picture is that concurrent eruptions from distinct vent areas at Stromboli are heralds of distinct magma differentiation conditions within the uppermost part of the storage region, in close agreement with the observed eruptive phenomena. This high-resolution approach has the potential to unequivocally constrain the processes driving transient, rapid, explosive eruptions in active volcanoes, thus offering new insights on the complex interplay between magma dynamics, magma ascent rate, and eruptive behavior.
Diagnosis of pollution events by NOx and CO Emissions calculated by Mass-Conserving Inversion method and composition of PM2.5 in Big City of Energy Rich Northern China
Authors: Li Xiaolu , Cohen Jason Blake , Qin Kai , Geng Hong
Published: February 2023

This work used a Mass-Conserving inversion estimate framework based on daily TROPOMI NO2 and CO columns and observed stack fluxes of large industrial and commercial combustion sources from the continuous emissions monitoring systems (CEMS) to quantify three years of daily-scale, grid-by-grid emissions of NOx and CO at 0.05°×0.05° over Shanxi Province. This region was selected due to its complex topography, rapid development, and the fact that it currently contributes to more than 25% of China’s total coal production and consumption. For these reasons, the region is also highly representative in terms of rapid changes in the spatial-temporal distribution of emissions found in many different regions of the Global South. The calculated emissions, their ratio, and the day-to-day emissions variability are calculated and explained over four different land-use types: rural, natural, urban, and industrial. It is observed that relatively high NOx emissions, high NOx/CO and high NOx/NO2 ratios are consistent with known industrial areas; relatively lower NOx emissions, high NOx/CO and low NOx/NO2 ratio are consistent with known urban aeras. While the time series of both NOx and CO emissions are found to decrease from 2019-2021 overall, there are some complicated inter- and intra-year variations in the emissions, and such trends are not statistically significant over specific sub-regions. The observed variations include both known and unknown special events, as results of intentional policy changes, properties of the climate, and long-range transport atmospheric events. Combined with the Empirical Orthogonal Functions Principal Components Analysis (EOF), the joint composition of PM2.5, NO2, and CO emission in the largest city in Shanxi show further insights. Special festivals and economic events including Chinese New Year are clearly observed. There is also a significant decrease in the NOx to CO emissions ratio observed in urban and rural areas during the COVID-19 induced lockdowns in 2020, but an obvious increase after first-order lockdown. Specifically, it is observed that while there was a drop from 2019 to 2020 due to the COVID lockdowns, that the lowest emissions levels observed actually were found in 2021. On top of this, there was an observed see-saw effect with further reduction of pollution from large enterprises and poorer control of small sources and residential combustion sources. Finally, a switch in the NOx to CO emissions ratio is observed to rapidly change for strict control measures were introduced during the 2022 Winter Olympics. Diagnosis of pollution events using emissions of NOx and CO integrated with detailed PM2.5 chemical components is successfully attempted for the first time.
On the sensitivity of the ocean response to LGM and MIS3-forcings
Authors: Jalihal Chetankumar , Merkel Ute , Prange Matthias , Mikolajewicz Uwe
Published: February 2023

The AMOC has undergone abrupt and quasi-periodic changes during the MIS-3. The prevailing background climatic conditions that produce such behavior in AMOC have yet to be fully understood. Previous studies have demonstrated that some climate models tend to have an oscillatory behavior in their AMOC under specific conditions that vary from model to model. A systematic study that compares these conditions across models is missing. Moreover, the relative impact of greenhouse gas and icesheet forcings on the mean strength of AMOC remain unresolved. Here, we present our results from CMIP/PMIP style simulations with MIS-3 boundary conditions. This study has been carried out under the PalMOD project. Based on the minimum and maximum ice sheet extent and greenhouse gas radiative forcing, we carried out a set of 4 experiments. These experiments are the LGM, 38ka, LGM_38kaghg (LGM topography with 38ka greenhouse gas concentrations), and 38ka_LGMghg (38ka topography with LGM greenhouse gas concentrations). We have used two Earth system models (ESM), Viz. the MPI-ESM and the CESM. The experiments in MPI-ESM were carried out with two versions of the river run-off directions - one in which run-off directions are compatible with the topography and the other where run-off directions are set to that of the modern-day. Thus, we have three sets of simulations for each experiment. A robust feature across these simulations is that during the MIS-3, the mean strength of AMOC is sensitive to changes in greenhouse gases, and the changes in ice sheets do not significantly affect the AMOC. The density of water in the North Atlantic Deep-Water formation (NADW) region does not change significantly in response to these forcings. However, the variations in the density in the Arctic and Southern Ocean deep-water formation region drive variations in AMOC strength. The AMOC in CESM undergoes Dansgaard-Oeschger (DO) like oscillations in the 38ka LGMghg simulation. No oscillations are found in any MPI-ESM experiments with the run-off adapted for topography. However, Bo-like oscillations appear in the LGM simulation with modern run-off. This highlights the importance of model parameters and the location of freshwater input into the ocean in determining the conditions that lead to oscillatory behavior in AMOC.
Spatio-Temporal Variations of Blue Slush and Water Flow in the Percolation Zone of Greenland: the Role of Local Topography
Authors: Covi Federico , Fahnestock Mark , Hock Regine , Xiao Jing , Rennermalm Åsa , Truffer Martin , Sturm Matthew , Benson Carl
Published: February 2023

The presence of thick ice layers in firn (so-called ice slabs) has the potential to increase the contribution to sea-level rise of the Greenland ice sheet. These impermeable ice layers prevent water percolation in the firn, leading to more efficient runoff by favoring lateral movement of water on top of the ice slabs. Here we use optical images from the Sentinel-2 satellites to track the seasonal and interannual evolution of snow fully saturated with water to the surface (blue slush) in southwest Greenland. Furthermore, we use a high resolution digital elevation model to assess the role of local topography on the formation of ice slabs and on lateral movement of water. We find that blue slush can reach elevations up to 1900 m a.s.l. in years with above average melt with maxima in August. Blue slush appears preferentially in areas where the surface slope approaches 0°, which is also where the ice slabs are thicker. The propagation of blue slush to lower elevation following local slope indicates water movement on top of the impermeable layer. Thus, we suggest that the process of formation of thick ice slabs is a self-sustaining positive feedback system.
Shell vs. plate tectonics: numerical stress quantification in a shortening lithosphere with strain localization
Authors: Halter William R. , Kulakov Roman , Duretz Thibault , Schmalholz Stefan M.
Published: February 2023

The mechanical characteristics of a shell, having a double curvature, are fundamentally different to the characteristics of a plate, having no curvature in its undeformed state. Geometrically, the Earth’s lithosphere is a shell rather than a plate. However, most geodynamic numerical models applied to study the deformation of the lithosphere do not consider this curvature. It is currently unclear whether the shell-type geometry of the lithosphere has a significant impact on lithosphere deformation on the scale of few 1000 kilometers. This study investigates the importance of considering lithospheric shells and compares numerical results of a shortening shell-type and plate-type lithosphere. We apply the two-dimensional state-of-the-art thermo-mechanical code MDoodz (Duretz et al. 2021). We consider a shortening lithosphere in an initially curved and in an initially rectangular geometry and calculate the spatio-temporal stress distribution inside the deforming lithosphere. We further present preliminary results on the effects and relative importance of various softening mechanism, leading to strain localization and subduction initiation, such as thermal softening, grain size reduction, or anisotropy generation due to fabric development. REFERENCESDuretz T., R. de Borst and P. Yamato (2021), Modeling Lithospheric Deformation Using a Compressible Visco-Elasto-Viscoplastic Rheology and the Effective Viscosity Approach, Geochemistry, Geophysics, Geosystems, Vol. 22 (8), e2021GC009675
Arctic Ocean mixing maps inferred from pan-Arctic observations
Authors: Waterman Stephanie , Dosser Hayley , Chanona Melanie , Shibley Nicole , Timmermans Mary-Louise
Published: February 2023

Quantifying ocean mixing rates in the Arctic Ocean is critical to our ability to predict upwards oceanic heat flux, freshwater distribution, and circulation. However, direct ocean mixing measurements in the Arctic are sparse and cannot characterize the high spatiotemporal variability typical of ocean mixing. Further, latitude, ice, and stratification make the Arctic Ocean mixing environment unique, with all of double-diffusive (DD), internal wave (IW)-driven and non-turbulent mixing processes playing a role.
In this work, we use year-round temperature and salinity data from Ice-Tethered Profilers (ITPs), as well as an archived record of ship-based measurements, to construct highly-resolved, pan-Arctic maps characterizing the relative prevalence of DD, IW-driven and non-turbulent mixing mechanisms based on thermohaline staircase identification and estimations of turbulence intensity. We next quantify pan-Arctic maps of estimates of average effective vertical diffusivity inferred from these observations that account for all of DD, IW-driven, and non-turbulent mixing processes. Finally, focusing on the water column segment directly above the Atlantic Water (AW) temperature maximum, we use this mixing regime characterization and regime-specific estimates of effective diffusivity to compute estimates of the pan-Arctic distributions of average vertical heat and buoyancy flux from the AW layer.
We find that estimates of effective vertical diffusivities are highly variable in both space and time. Although variability in diffusivity reflects both variations in the prevalence of the various mixing processes and variability in the strength of IW-driven mixing, the prevalence of the mixing mechanisms (predominantly DD and non-turbulent in the basins vs. IW-driven on the shelf) sets the dominant large-scale spatial patterns and the notable shelf-basin contrast. Estimated heat fluxes out of the AW layer also exhibit distinct regional patterns set by mixing mechanism prevalence and regional patterns in the vertical temperature gradient. Buoyancy fluxes from DD mixing compete with the destabilizing effects of IW-driven mixing in the basins, a competition that may be an important control on stratification in the Arctic Ocean interior.
These results are significant as they show that mixing mechanism prevalence is an important consideration in computing robust estimates of average effective diffusivity. They further suggest that the sensitivity of mixing rates to changing environmental conditions may have important regional dependencies owing to differing prevalence of the various mixing processes.
A song of ice and friction: the impact of basal friction and proglacial lakes on Pleistocene glacial cycles
Authors: Scherrenberg Meike D.W. , van de Wal Roderik S.W. , Berends Constantijn J.
Published: February 2023

During the Mid Pleistocene Transition (MPT; 1.2-0.7 Ma) the periodicity of glacial cycles changed from 40 ka to ~100 ka, without a coinciding change in orbital forcing. The MPT therefore results from feedback and changes in the climate system and ice dynamics triggered by the changes in radiative forcing. However, it remains unclear which physical processes are critical for the transition.Here we explore the role of basal sliding and glacial isostatic adjustment (GIA) in the MPT. Basal sliding is thought to have changed across the MPT due to the erosive action of the ice sheets gradually removing the regolith cover and exposing the underlying bedrock, therefore increasing the friction at the base. GIA modulates this effect by enabling the formation of large proglacial lakes, changing the ice margin from a land-based to a marine environment. We simulate the evolution of the Northern Hemisphere ice sheets during the past 1.5 million years, using an ice-sheet model forced by a climate matrix method.We show that changing the basal friction has an effect on glacial terminations and consequentially glacial cycle periodicity. Larger friction leads to thicker ice sheets that are more likely to survive a climatic optimum. However, we show that using an unchanging friction coefficient through the Pleistocene, our model still produces change from 40 ka to 100 ka periodicities signifying the MPT. This suggest that the regolith hypothesis is not necessary to explain the MPT.In addition, we show that the formation of proglacial lakes is required for achieving a full deglaciation of the large Late Pleistocene ice sheets. Ice that floats on water experiences no friction at the base, resulting in high ice velocities. This results in more ice in lower regions and enhances the melt of ice. Here, we find a strong modulating role of GIA. When neglecting bedrock adjustment, thus preventing the formation of large proglacial lakes, we fail to simulate a full deglaciation.
Development of Geostationary Satellite Atmospheric Motion Vectors Forecasting Algorithm by CNN Model
Authors: Choi Hwayon , Choi Yong-Sang , Kim Gyuyeon
Published: February 2023

Atmospheric motion vector (AMV) is an important factor that affects most meteorological phenomena in numerical weather prediction. Despite of its significance, the conventional algorithm of moisture tracking for AMV calculated with most of remote sensing data uses the cross-correlation coefficient (CCC) method, resulting in low-resolution (target-based) output and much of errors. In addition, forecasting AMVs is impossible in conventional method because it requires water vapor data 10 minutes from the current time to calculate current winds. For better moisture flow tracking, convolutional neural network (CNN) frames were used that track motion, which is called optical flow estimation in computer vision. The pixel-based high-resolution AMVs are calculated by using the water vapor channel images into the PWC-Net (CNNs for optical flow using pyramid, warping, and cost volume). For each pixel, linear regression is used to forecast AMVs. The performance of the AMVs calculated by CNN was validated by comparing those results and the Korean geostationary satellite GEO-KOMPSAT-2A (GK2A) AMVs with wind fields of ERA5 data at 100-1000 hPa. Experiments used infrared brightness temperature images of three water vapor channels at 6.2 µm, 7.0 µm, and 7.3 µm over Korean Peninsula for 2022. As to root-mean-square vector differences (RMSVDs), the tracking performance of this study was found to be more accurate than the GK2A AMVs ­— 1.3 to 21.93 m/s more accurate for the cloudy sky and 0.32 to 14.9 m/s more accurate for the clear sky above 400 hPa. The results using the CNN model showed better moisture tracking performance than the conventional method, especially for low altitudes. It also enables to obtain higher resolution AMVs with pixel-based tracking rather than conventional target-based tracking. Furthermore, the mean RMSVDs of forecasted AMVs are 1.97 m/s, 2.66 m/s, 3.32 m/s, and 5.28 m/s when the forecast lead time is 10 min, 20 min, 30 min, and 1 hr, respectively. Consequently, high-resolution AMV forecasts with accuracy, which could not be calculated by the conventional method, were obtained by CNN model, and can be used to advance the accuracy of weather forecasting. KEYWORDS: Moisture Tracking; Optical Flow; Atmospheric Motion Vectors; Wind Forecasting; Remote Sensing
Thermally-controlled direct shear tests at the soil-concrete interface
Authors: Lupattelli Arianna , Salciarini Diana , Brunelli Benedetta , Cattoni Elisabetta
Published: February 2023

The promotion of Energy Geostructures (EGs) is strongly related to the use of renewable and clean energy resources for the heating and cooling of buildings. They couple the structural role of geostructures with the exploitation of Low Enthalpy Geothermal Energy (LEGE). During their operation, EGs are continuously subjected to thermal variations, due to the heat exchange between the soil and heat transfer fluid circulating in the pipes inserted in the structure. This can lead to an impact on the mechanical response of the structure, and the role of the soil-structure interface takes on relevance in this operation. Nevertheless, experimental results deriving from the literature on the Thermo-Mechanical (TM) soil-structure interface behavior suggest that the effect of temperature on the shear resistance is quite limited, in the case of interaction with a building material such as concrete, especially for coarse-grained soils. The case of fine-grained soils is more complex: some studies suggest an enhancement of the interface shear strength, showing an increase of adhesion or a slight increase in friction angle at the interface during heating; while other studies show no significant variations of the interface behavior with thermal cycles. Such differences are likely due to the multitude of experimental configurations, development protocols, and composition of the samples used during tests. With the aim of better understanding this controversial framework on the interface behavior, a modified device for direct shear tests was developed at the Laboratory of Geotechnical Engineering of the University of Perugia: starting from the conventional direct shear apparatus, this has been equipped with a heating cement plate, where a thermal resistance and a temperature probe for continuous temperature control have been integrated. The first tests on silty sand reconstituted samples have shown that the thermal effects at the interface are limited to a decrease in shear strength of less than 3%.
WRF with age-weighted water tracers: implementation, application, and new insights into the regionally accelerated atmospheric hydrological cycle under global warming
Authors: Wei Jianhui , Arnault Joël , Rummler Thomas , Fersch Benjamin , Zhang Zhenyu , Olschewski Patrick , Laux Patrick , Kunstmann Harald
Published: February 2023

Atmospheric water residence time, here defined as time between the original evaporation and the returning of its respective water masses to the land surface as precipitation, is a measure of the speed of the atmospheric hydrological cycle. Traditional analytical methods are generally limited by crude assumptions in the coupling between the land surface and the atmosphere, and hence are not applicable to regions with complex monsoon systems under a changing climate. To this end, we have implemented the age-weighted water tracers into the Weather Research and Forecasting WRF model, namely, WRF-age, to follow the atmospheric water pathways and to derive atmospheric water residence times accordingly. The newly developed, physics-based WRF-age is used to regionally downscale the reanalysis of ERA-Interim and the MPI-ESM Representative Concentration Pathway 8.5 scenario (RCP8.5) simulation for an East Asian monsoon region, i.e., the Poyang Lake basin, for two 10-year slices of historical (1980-1989) and future (2040-2049) times. In comparison to the historical WRF-age simulation, the future 2-meter air temperature rises by 1.3 °C and precipitation decreases by 38% under RCP8.5 on average. In this context, global warming leads to decreased atmospheric residence times of the column-integrated water vapor (from 22 to 13 hours) and column-integrated condensed moisture (from 26 to 14 hours) in the atmosphere over the basin, but slightly increased atmospheric residence times of surface precipitation (from 12 to 15 hours) in agreement with reduced the precipitation amounts. Our findings demonstrate that global warming increases the complexity of regional atmospheric water cycle, especially the associated changes in the residence times of atmospheric water states of matter.
Lacustrine oncoids and thrombolitic clots mixed with terrigenous clasts in the Lower Cretaceous Junggar Basin, Central Asia
Authors: Guan Xutong , Wu Chaodong
Published: February 2023

Oncoids and thrombolites are microbial carbonates and important indicators for paleogeography. We firstly found lacustrine oncoids and thrombolitic clots mixed with terrigenous clasts in the Lower Cretaceous in the Junggar Basin in Central Asia and aimed at their mixing process and the paleogeographic significance. We conducted a comprehensive petrological study including optical, cathodoluminescence, fluorescence, quantitative evaluation of minerals by scanning electron microscopy, Raman spectroscopy, carbon and oxygen isotopes. Intraclasts, calcite spherulites, botryoidal grains, cortoids, and ooids also mixed with the terrigenous clasts. The cortices of oncoids and ooids are composed of layers of organic carbon-rich micrites, sparry calcites, and apatites. Some oncoids exhibit alternating dark and light laminae with unequal thicknesses and binding structures of microbiota. Thrombolitic clots grew with silt-sized terrigenous clasts and ooids. Grains were cemented by fibrous, dog-tooth, and interstitial granular calcite cement, and some grains are enveloped by micrites. Compared to published data in the Tianshan Region and the Junggar Basin, positive δ13C of the mixed siliciclastic-carbonate sediments may indicate the 12CO2 absorption of microbiota. Based on the geomorphology and sedimentary distribution, we concluded that mixed siliciclastic-carbonate sediments were developed on a gentle slope with a relatively inadequate sediment supply during highstand periods. The sparry calcite-cemented mixed siliciclastic-carbonate sediments experienced rapid in-situ mixing process in an agitated lakeshore environment. Sparry carbonate cortices peeled off from the oncoids were densely packed in a shallow lake environment. These mixed siliciclastic-carbonate sediments were sedimentary response to extensive lake transgression and humidification in the Early Cretaceous following coarse-grained alluvial sediments and aridification in the Late Jurassic. 
Characterization of soil properties and soil ecosystem services in meadows from a high Mediterranean mountain (Sierra de las Nieves National Park, southern Spain).
Authors: Menjíbar-Romero Mario , Martínez-Murillo Juan Francisco
Published: February 2023

Soils in meadows from high Mediterranean mountains play an important role from the ecosystem service point of view: e.g., regulating water cycle and capturing soil organic carbon, provisioning support to herbaceous plants and thus grass for wild animals and cattle, and cultural aesthetic values to mountainous landscape. These soils are threatened by global warming because it may bring modifications in vegetal species, vegetation type, and coverage. Also, an increment in grazing pressure may lead to a decrease in vegetation cover and thus enhancing soil degradation as well as increasing water erosion. All these would implicate modifications in the provided ecosystem services.To investigate the soil ecosystem services provided by soils from meadows located in the upper part of a Mediterranean mountain (Sierra de las Nieves National Park), a first approach to characterize their properties was conducted. These meadows are located above 1,700 m.a.s.l., are related to the presence of marly bedrock where shrub cover is less than 50%, mainly, because of the coat and sheep grazing activity is not intensive. To do this, firstly, meadow soils were randomly sampled in the upper 0-10 cm of depth collecting disturbed and undisturbed samples. Once these samples were dried in laboratory, the following properties have been analysed: bulk density, gravel content, texture, aggregate stability fraction, organic carbon content, organic matter content, pH, electrical conductivity, cationic exchangeable capacity, cations, saturation in bases, and water holding capacity in field and wilting points. After the data validation one statistical analysis will be performed for a broad characterisation and preliminary evaluation of soil ecosystem services.
GEB: A large-scale agent-based socio-hydrological model – simulating 10 million individual farming households in a fully distributed hydrological model
Authors: de Bruijn Jens , Smilovic Mikhail , Burek Peter , Guillaumot Luca , Wada Yoshihide , Aerts Jeroen
Published: February 2023

Humans play a key role in the hydrological system, and their decisions influence the entire water system from tributary to river mouth. To fully comprehend how the human-natural water system evolves over space and time, and to investigate the systemic effects of climate change and human interventions, it is important to consider human behaviour and feedbacks to the hydrological system simultaneously at the local household- and large basin scales.Therefore, we present GEB (Geographical, Environmental and Behavioural model); an agent-based model coupled to a fully distributed hydrological model that can simulate the behaviour and daily bi-directional interaction of more than 10 million individual farm households and reservoir operators with the hydrological system. Through this coupling, each individual farmer with unique characteristics and location can make daily decisions, such as irrigating their crops from surface-, reservoir-, or groundwater, planting and harvesting crops, investing in adaptation options (e.g., irrigation wells and sprinkler irrigation). All these decisions can be based on the available water in their environment, the status of their crops, their risk perception, crop price, water price, and weather conditions etc. Similarly, reservoir operators can regulate the availability of water for irrigation, and downstream releases of water based on the state of the hydrological system as well as communication with farmer agents.GEB is dynamically linked with the spatially distributed hydrological model CWatM at 30’’ grid resolution (< 1km at the equator). Because many small-holder crop fields are much smaller, CWatM was specifically adapted to implement dynamically sized hydrological response units at field scale / sub-grid level, providing each agent with an independently operated hydrological environment.While the model could be applied anywhere, we show an implementation with local and basin-wide feedbacks in the heavily managed Krishna basin in India, encompassing ~8% of India’s land area and ~12.1 million farmers. Here, we quantify bi-directional feedbacks such as the reservoir paradox and test various policies, such as providing subsidies for adaptation options (e.g., irrigation wells, sprinkler irrigation), and quantify effects on the hydrological system as well as downstream farmers.In this implementation, GEB uses approximately 15 GB of RAM memory and can thus be used on an above average personal laptop. Computational requirements scale linearly with basin size, assuming similar farm-size distribution.
Coupled modelling of soil structure dynamics, carbon cycling, hydrological processes and crop production
Authors: Jarvis Nicholas , Coucheney Elsa , Larsbo Mats , Lewan Elisabet , Meurer Katharina
Published: February 2023

Soil-crop models are potentially useful tools to support analyses of the effects of climate and crop and soil management practices on crop production and the environment (e.g. carbon sequestration and greenhouse gas emissions or the leaching of agro-chemicals). However, it is not clear whether current generation models can be used to simulate long-term trends in crop production and the environmental impacts induced by changes in climate or land use because they do not consider the effects of soil structure dynamics at seasonal to decadal  (e.g. root growth, activity of macro-fauna) and centennial time scales (e.g. changes in organic matter content) on soil hydraulic functions, hydrological processes, crop growth and carbon cycling.Here, we present a new soil-crop model that accounts for the interactions between soil structure dynamics, carbon cycling, soil physical and hydraulic properties, soil water balance and crop growth. The importance of soil structure dynamics is illustrated by long-term simulations of soil organic matter storage, soil water balance components and crop yields for a field site in central Sweden under climate change and contrasting management practices (organic amendments and crop varieties with an enhanced allocation of carbon to roots).
Drained, dampened, delayed: Deep soil moisture dynamics
Authors: Blume Theresa , Rasche Daniel , Güntner Andreas , Morgner Markus
Published: February 2023

Soil moisture is most often measured in-situ only to depths of about 50 cm. This is due to either the larger effort or challenges in installation or at some sites due to the presence of weathered bedrock. It is furthermore often assumed that with the top 50 cm of the soil we already capture the main part of the root zone and thus the major processes of infiltration, evaporation and transpiration should all be reflected in these soil moisture observations. However, due to lack of data we cannot be sure that this is really the case.In this study we are reviewing soil moisture dynamics measured in the field at depths ranging between 70 and 450 cm. This includes more than 100 sensors at depth >70 cm and more than 60 at depth >100 cm. These sensors are installed in sandy soil in 14 different forest stands of the TERENO observatory in north-eastern Germany. We examine both seasonal and event responses. We furthermore compare the responses in the unsaturated zone also to the responses observed in shallow and deep groundwater. Using simple uncalibrated 1D Hydrus simulations we then put our observations into the context of those simulated by the model under pure matrix flow conditions, thus ignoring any preferential flow. The above described setup allows us to investigate the effects of infiltration, percolation, preferential flow, deep drainage, and transpiration at depths usually not accounted for in standard monitoring networks.