bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of space-time dynamics of precipitation on timing and shape characteristics of runoff events
Authors: Tarasova Larisa , Aala Safae , Ribbe Lars , Kumar Rohini
Published: February 2023

The observed variability in shape and timing characteristics of event hydrographs emerges from the variability in the types and structure of the corresponding hydrometeorological events and their interaction with the variable catchment states. The increasing temporal resolution of available hydrometeorological data provide a possibility for deciphering the effect of space-time dynamics of precipitation on the characteristics of event hydrographs and might provide useful insights into the differences on the controls of small and large runoff events. In this study, we comprehensively analysed the effects of the spatio-temporal dynamics of precipitation on the characteristics of hourly event hydrographs using the analytical framework of Viglione et al. (2010). We examined eight properties reflecting the shape and timing characteristics of 2026 hourly event hydrographs and 20 indicators describing the spatio-temporal structure of precipitation and pre-event wetness states in seven contrasting catchments in the Bode River basin, located in central Germany, using random forests and Accumulated Local Effects (ALE) techniques.We found that the steepness of the rising limbs of event hydrographs is controlled by the intensity of precipitation, its temporal dispersion, and the catchment-averaged storm velocity. The contribution of these indicators is even more apparent for large runoff events (i.e., events with larger peak discharges). Instead, the event time scale of the hydrographs is rather affected by the volume of precipitation and antecedent base flow in combination with the spatial properties of precipitation (its spatial spread and proximity to the catchment outlet). Moreover, we found that the duration of precipitation events plays a major role in defining the response time of catchments. Finally, our results demonstrate that the effects of spatio-temporal structure of precipitation for the shape and timing characteristics of hydrographs are especially prominent for larger events, indicating the potential importance of these features for accurate flood forecasting and constructing of design synthetic hydrographs. The future effort will focus on examining the validity of identified controls for a larger and more diverse set of catchments in Germany.ReferencesViglione, A., Chirico, G. B., Komma, J., Woods, R., Borga, M., and Blöschl, G. (2010). Quantifying space-time dynamics of flood event types. Journal of Hydrology, 394 (1-2):213–229.
Local resources for dike revetment in managed realignments
Authors: van den Hoven Kim , Grashof-Bokdam Carla J. , Slim Pieter A. , Wentholt Ludolph , Peeters Patrik , Depreiter Davy , Koelewijn André R. , Kroeze Carolien , van Loon-Steensma Jantsje M.
Published: February 2023

Managed realignment is the landward relocation of flood infrastructure to reintroduce the tide on former reclaimed land. A managed realignment site is an ecological restoration site. At the same time, it forms a new type of hybrid flood defence that makes use of Natural and Nature Based Features. Nature-based flood protection is provided by the flood risk reduction capacity of the restored habitat such as saltmarshes, complemented by the landward relocated flood defence infrastructure, i.e., the realigned dike. The realigned dike is either a (reinforced) existing or newly constructed dike. The realigned dike can be built or reinforced from local resources such as the saltmarshes and formerly reclaimed land. Material from the removed dikes can also be re-used. In history, saltmarsh sods have been used as building material for the dikes themselves and for their revetment. The sods were also used as emergency dike repair material. In addition to the use of local resources as building material for flood infrastructure, the mining of local resources can simultaneously support nature restoration under the dynamic circumstances of the coast.      We tested the historic sod technique for dike revetments at a managed realignment project in progress where the dikes were available for real size experiments. On a dike with grass revetment, we studied the erosion resistance of transplanted dike grass sods after one growth season. Grass sods were transplanted to the inner and outer dike slope. The erosion resistance of the transplanted sections was tested under calm and extreme conditions with a grass pull test, a wave impact simulator, an overflow generator, and by analysing roots development. After one growth season, we found that the vegetation of transplanted sods continued to grow and started to connect to the original dike revetment. While some erosion occurred under extreme circumstances, the grass pull test revealed the transplanted sod revetment was stronger than a bare clay revetment. The erosion resistance of transplanted sods after one growth season is promising when compared to for instance a newly seeded grass revetment.      In conclusion, the sod application technique can provide local resources for the revetment of realigned dikes. Sod transplantation can also be used to introduce target species at for instance the dike toe. At the same time, mining of (grass) sods from former land or saltmarshes can support nature restoration and development. Our results can hereby contribute to increase our ability to design flood infrastructure with Natural and Nature Based Features.
Utilizing UAV-Based Hyperspectral Imaging to Detect Surficial Explosive Ordnance
Authors: Tuohy Madison , Baur Jasper , Steinberg Gabriel , Pirro Jalissa , Mitchell Taylor , Nikulin Alex , Frucci John , De Smet Timothy
Published: February 2023

 Around the world, approximately 110 million explosive ordinances (EO), including remnant antipersonnel landmines, antivehicle/tank mines, unexploded cluster munitions, improvised explosive devices (IEDs), explosive remnants of war (ERW) like unexploded ordnances (UXOs) and abandoned explosive ordinances (AXOs), remain untouched and undetected in post-conflict nations. Current geophysical EO detection methods include ground-based electromagnetic induction (EMI), which has proven to be costly, dangerous, and time consuming. Recent hardware advances have allowed for drastic reductions in the size, weight, power, and cost (SWaP-C) of miniaturized geophysical sensors. Sensors like hyperspectral imaging (HSI) systems can now be successfully mounted to small unpiloted aerial vehicles (UAS). In this proof-of-concept study, we combine UAV-based HSI in an attempt to develop and calibrate a safer, faster, and more cost efficient method of remote detection of surficial EO. We collected data with a Corning microHSI 410 selectable hyperspectral airborne remote sensing kit (SHARK) attached to a DJI Matrice 600 with a Ronin-MX gimbal in simulated minefields over several different environmental settings. We emplaced multiple types of ERWs, including anti-personnel mines, anti-vehicle mines, rockets, missiles, and grenades. Significantly, several of these are currently being used in the Russo-Ukrainian War, including: TM-62M and TM-62P antivehicle mines; 40 mm submunitions; OZM-72, PFM-1, PMN, and PMN-4 antipersonnel mines; 82 mm mortars; multiple types of cluster bombs; 122 mm GRAD rockets; PG-7 rocket propelled grenades; and several fuzes. We found that HSI proved to successfully image a variety of EO, from large PG-7 rocket propelled grenades (RPGs) to the small, notoriously difficult to detect, minimal metal PFM1 anti-personnel landmine. This study allowed us to better understand the strengths and weaknesses of UAV-based HSI to detect and spectrally quantify ERW of various sizes and material compositions. Our analysis demonstrated that unique spectral profiles and derivative data products can be created to identify multiple EO in relatively high resolution hyperspectral images and in variable environments. Future research will integrate HSI data as additional channels to the convolutional neural network (CNN) algorithm our group has been developing. 
Investigating Mauna Loa (Hawaii) eruption of November-December 2022 from space: recent results from GOES-R, Sentinel-2, and Landsat 8/9 observations
Authors: Pergola Nicola , Genzano Nicola , Plank Simon , Marchese Francesco
Published: February 2023

On 27 November 2022, an eruption started at the Mauna Loa (Hawaii; USA) volcano after about 38 years of quiescence. The eruption took place at the summit caldera; the day after, it migrated to the upper Northeast Rift Zone, where lava effusion initially occurred from three fissure vents. In this work, we investigate the Mauna Loa 2022 eruption, ending on 13 December, by means of a virtual network of multi-sensor infrared satellite observations. In particular, we show the results achieved by implementing the Normalized Hotspot Indices (NHI) on GOES-R ABI data, at 10 min temporal resolution, and by using Sentinel-2 MSI and Landsat-8/9 OLI/OLI-2 observations at mid-high spatial resolution via the Google Earth Engine tool developed to map volcanic thermal anomalies at global scale.. Both the eruption onset and the short-term variations of thermal activity were well identified by NHI, using GOES-R ABI data. Moreover, an accurate mapping and characterization of active lava flows was performed. These results confirm that SWIR (short wave infrared) observations, at different temporal and spatial resolution, if properly analysed, may support the monitoring and surveillance of active volcanoes from space.
The impact of geology on sediment dynamics. A modelling approach for the Northern Franconian Jura, Germany.
Authors: Ringleb Bastian , Fuchs Markus
Published: February 2023

Landscape Evolution Models (LEMs) are powerful tools for simulating erosion and accumulation patterns over a landscape. To accurately capture the complexity of the system, several parameters are used to describe the flow of water on a surface and thereby calculate a change in landscape. However, due to the need for reasonable computing power, simplification is often necessary. The CAESAR-Lisflood LEM simplifies the transition from precipitation to runoff with a cell storage-based system, where water is retained in each cell and released at later iterations, simulating infiltration and forming the hydrograph. This reduced complexity works well for surface processes, but can lead to issues in catchments, where ground water flow and infiltration are unknown parameters, and an unknown proportion of sediment transport is connected to sub-surface processes.Located in the Northern Franconian Jura, Germany, the Weismain River catchment (~125 km2) is a particularly challenging area to model the sediment dynamics, due to its karstic geology. The Weismain river and its tributaries are deeply incised into a limestone plateau forming small, well-defined valleys opening to wider floodplains in the lower parts of the catchment, where sandstone is dominant. To gain a better understanding of the sediment dynamics and the evolution of this catchment, the impact of the karstic environment needs to be evaluated. With CAESAR-Lisflood we are looking at the spatial distribution of alluvial sediment from different model inputs and how differences in discharge calculations affect model results. With this model setup we can gain insight into the sediment dynamics of the catchment and increase confidence in future results.
Multi-hazard risk assessment of extreme weather events in a changing climate
Authors: Stalhandske Zélie , Steinmann Carmen , Bresch David N. , Kropf Chahan
Published: February 2023

Extreme weather events are among the most destructive natural hazards, affecting a large number of people and causing significant monetary damage globally each year. The impact of these events is increasing due to climate change and socio-economic development. While traditional approaches to risk assessment have focused on the impacts of single hazards, the combined risk of multiple hazards may be different from their sum. Their spatial and temporal co-occurrence may also be influenced by climate change. In this study, we develop a framework for modelling the combined risk of multiple climatic hazards, where risk is defined as the combination of hazard, exposure and vulnerability. We illustrate this method based on globally consistent river floods and tropical cyclones and their impacts on both population and assets. Both hazards are driven by global climate models to investigate their risk at current and future levels of warming. The combined impacts are evaluated by aggregating single hazard models on an event basis, where events are driven by the same climate model outputs. This allows us to not only consider the average annual impact, but also for example to assess combined extreme events or return periods. Additionally, spatially and temporally compounding events can be analysed. This framework is implemented in the open-source climate risk platform CLIMADA and can be applied to different climate risks, providing a more comprehensive approach to understanding and managing the risks posed by extreme weather events in a changing climate.
The Angular Distribution of Whistler-Mode Chorus Wave Vector Directions from Van Allen Probes and MMS Observations
Authors: Hartley David P. , Christopher Ivar , Chen Lunjin , Santolik Ondrej , Kletzing Craig , Argall Matthew , Ahmadi Narges
Published: February 2023

The dynamics of Earth's outer electron radiation belt is, in part, driven by interactions with whistler-mode chorus waves.  Chorus can cause rapid acceleration of electrons up to relativistic energies, as well as drive precipitation of particles into the atmosphere causing both microbursts and diffuse aurora.  Chorus can propagate in such a way that it crosses the plasmapause boundary and may contribute to the possible sources of plasmaspheric hiss, which itself can cause atmospheric losses of particles and the formation of the slot region between the inner and outer radiation belts.  The direction of the wave vector relative to the background magnetic field is a key parameter for quantifying these processes, since it determines the propagation trajectory of the wave, and is required for calculating the resonance condition of the wave-particle interaction.The orientation of the wave vector is investigated using both survey mode data and high-resolution burst mode observations from the EMFISIS Waves instrument on the Van Allen Probes spacecraft.  Spatial coverage beyond the Van Allen Probes orbit is provided by burst-mode observations from the FIELDS instrument suite on Magnetospheric Multiscale (MMS).  The polar and azimuthal wave vector angles are considered using both spectral analysis, where the frequency-time structure can be resolved, and instantaneous values, which can be used to identify variations within individual chorus subpackets.  We compare the results from each of these different timescales.  Near strong plasma density gradients, such as those which occur on the boundaries of plasmaspheric plumes, we identify that the wave vector becomes more oblique than the general case where no density gradients are present.  The obliquity of the wave vector is shown to directly relate to both the magnitude of the density gradient, and its proximity to the spacecraft.  
The multiverse future of ENSO diversity in large ensembles of climate models
Authors: Dieppois Bastien , Maher Nicola , Capotondi Antonietta , O'Brien John
Published: February 2023

El Niño Southern Oscillation (ENSO) shows large differences from one event to another in terms of its intensity, spatial pattern, and temporal evolution, which are typically referred to as “ENSO diversity”. While such differences in ENSO patterns are associated with different regional climate impacts throughout the world, influencing the skill of impact prediction systems, large uncertainties remain concerning its potential future evolution and trends. The location and intensity of ENSO events are indeed strongly influenced by internal/natural climate variations, limiting the detection of forced changes.Here, we exploit the power of single model initial-condition large ensembles (SMILEs) from 13 fully coupled climate models from both CMIP5 and CMIP6 (totalling 580 realizations in historical and SSP-RCP scenarios) to first examine the ability of climate models to simulate realistic diversity of ENSO events compared to multiple observational datasets, and then use those models to characterize future trajectories in the location and intensity of El Niño and La Niña events. We define the location of ENSO events as the longitude of the absolute maximum (the intensity) of sea-surface temperature anomalies (SSTa) during boreal Winter (December-February) in the equatorial Pacific. Future projections of ENSO diversity are assessed in terms of joint probability distributions of ENSO events’ location and intensity.While some models show a degree of diversity in the location and intensity of events that are comparable with observed statistics, other models tend to favour the occurrence of eastern or central Pacific events. Such contrasting performances during the historical period are found to be associated with different future trajectories of ENSO diversity: i) models favouring the occurrence of eastern Pacific events (e.g., ACCESS-ESM1-5, CanESM2, and 5) show a westward shift in event location over the 21st century; ii) models simulating ENSO events anomalously westward tend to show an eastward shift in event locations and an increased intensity in the 21st century (e.g., CESM1 and 2, CSIRO-MK3-6-0, GFDL-CM3, GFDL-ESM2M, MIROC-ES2L, MIROC6). Nevertheless, we note that models showing the closest match to observed statistics during the historical period also present a westward shift in ENSO locations and a slight increase in intensity in the 21st century (e.g., GFDL-SPEAR and IPSL-CM6-LR).Although the physical cause of model discrepancies remains unclear, this study provides a broader perspective on expected ENSO changes over the 21st century in different models and highlights the spread of projections among models.
Combined effect of basalt dust foliar distribution and water availability on leaf morpho-physiological traits and grape quality in Falanghina
Authors: Petracca Francesca , Cirillo Chiara , Bonfante Antonello , Arena Carmen , Giulioli Marco , Erbaggio Arturo , Amitrano Chiara , De Micco Veronica
Published: February 2023

Climate change in the internal areas of the Mediterranean region is causing a decrease in the frequency of rains and an increase in temperatures, leading to dryer and warmer seasons. These conditions, which will become more and more intense in the coming decades, are already affecting viticulture (e.g. photoinhibition, leaf and berry sunburn) influencing the growth and physiology of vines together with the yield and quality of grapes. The sustainability of vine cultivation in these areas is increasingly at risk, thus, the definition of sustainable cultivation techniques is pivotal to stabilize production and maintain high quality standards of the grapes.The aim of this work is to evaluate the effects of the application of basalt dust on the leaf surface of Vitis vinifera L. subsp. vinifera ‘Falanghina’ grapevine, grown under two different water availability levels over two years characterized by different climatic conditions. The experiment was conducted between 2021 and 2022 in a commercial vineyard of La Guardiense farm at Guardia Sanframondi (Benevento, southern Italy), in the Sannio wine district. The treatment blocks set, localized after geo-physical analysis of the soil, were the following: DI (distribution of basalt dusts and irrigated; Dust-Irrigated), DR (distribution of basalt dusts and rainfed; Dust-Rainfed), NDI (without basalt dusts and irrigated; No Dust-Irrigated), and NDR (without basalt dusts and rainfed; No Dust-Rainfed). The basalt dusts were distributed during the productive-vegetative cycle of the vine (from April to September) and the irrigation was managed according to weather conditions and soil water availability. During the two years of trials, the vegetative growth was monitored through biometric measures, the eco-physiological characteristics through leaf gas-exchanges, chlorophyll “a” fluorescence emission and leaf water potential, during the four main phenological phases: flowering, fruit set, veraison and maturation. Eco-physiological traits were also linked to leaf functional anatomical traits (e. g. lamina thickness, localization of phenolics, stomatal size and frequency) to detect mechanisms for acclimation. After the measurement of fertility, the grapes from each plot were harvested and micro-vinified. The musts and wines were chemically characterized to understand the oenological potential of each one. The analysis of the data from the two seasons 2021 and 2022 allowed us to unravel the effect of inter-annual climatic variability on the potential for photoprotection of the dust distribution. Gained information is useful to evaluate whether the use of basalt dust can be considered a tool for mitigating water stress and rationalizing irrigation protocols.
hydroweb.next, an open-data WebGIS platform to bring state-of-the-art products derived from satellite remote sensing to hydrology users
Authors: Gasnier Nicolas , Zawadzki Lionel , Gouillon Flavien , Specht Bernard , Cauquil Pascal , Pena Luque Santiago , Dupuis Aurore , Martin Vincent , Sand Aurélie , Barroso Thérese , Picot Nicolas , Strzepek Aurélie , Maisongrande Philippe
Published: February 2023

The hydroweb.next platform is an open-data thematic hub for hydrology. It aims to foster new uses of remote sensing data for water applications by removing the main barriers: data formatting issues, dispersal of access points, and data processing costs,…Hydroweb.next has been funded by the French government in the frame of Theia (Data and Services center for continental surfaces) and SWOT downstream (Surface Water and Ocean Topography satellite) programs. The hub brings together products from various providers such as Copernicus Land Services along with products from its own production centers. The production centers operate state-of-the-art algorithms that have been developed with scientists from Theia’s Scientific Expertise Centers: SurfWater for Surface Water Extent (SWE) from Sentinel-1 and Sentinel-2 images, Let It Snow for fractional snow cover and OBS2CO for water quality from Sentinel-2 images. As of June 2023, these 3 products will be made available with a 5 million square kilometer coverage. Products from SWOT and Trishna missions will also be distributed by hydroweb.next as they become available. In late 2023, SWOT data will include high-level user-oriented products such as river discharges and lake storage changes with global coverage. In 2025, Trishna products will include water quality, water skin temperature, and evapotranspiration. In situ data are also available to allow comparison with satellite data.The products are distributed using STAC (Spatio-Temporal Asset Catalog) and WMS/WMTS (Web Mapping Services) protocols that follow the FAIR principles. This enables the direct reuse of the data by other services (e.g. UNESCO’s water quality portals).The WebGIS interface is designed following a User-Centered Development approach. By involving users from various backgrounds such as Water Agencies, NGOs, industry, or academic research in stages of the project: surveys of user needs during interviews, features design involving users, ergonomics improvement through alpha testing, and quick consideration of user feedbacks through continuous integration and deployment. The interface allows searching relevant data using keywords, geophysical variables, and space-time restrictions. It also allows visualizing the products, their temporal evolution, and multitemporal synthesis. Finally, it allows downloading, harvesting, or streaming data, either through the interface or python APIs.
H2O-present melting curve of magnesite and trace element distribution during melting of (dry) magnesite and calcite in the upper mantle
Authors: Sieber Melanie J. , Reichmann HansJosef , Farla Robert , Appelt Oona , Oelze Marcus , Lathe Christian , Koch-Müller Monika
Published: February 2023

The presence of magnesite (MgCO3) in the Earth’s mantle plays a fundamental role in reducing the melting point of the mantle [1] and forming carbonate‑rich melts such as kimberlites and carbonatites [2]. The melting curve of (dry) magnesite is well constrained [3, 4], but melting of magnesite in the presence of H2O, providing the basis for more complex (natural) systems, is poorly understood from some quenched experiments [5]. Also, the distribution of trace elements such as Li, Sr, Pb, and rare earth elements during melting of magnesite is poorly considered in models that evaluate the trace element budget of carbonate‑rich melts parental to kimberlites [6].Here we report, first, the H2O‑present melting curve of magnesite between 2 and 12 GPa. The melting curve of magnesite mixed with 16 wt% brucite was established by in ‑ situ X‑ray diffraction measurements using the large volume press at P61B at PETRA III (DESY). Second, we report trace element partitioning data for congruent melting of calcite and incongruent melting of magnesite producing carbonate melt and periclase between 6 and 9 GPa. Those results were obtained from quenched experiments using a rocking multi‑anvil press at the GFZ overcoming equilibrium and quenching problems in previous studies [7]. 1          Dasgupta and Hirschmann, The deep carbon cycle and melting in Earth's interior. Earth and Planetary Science Letters, 2010. 298(1-2): p. 1-13.2          Jones, Genge, and Carmody, Carbonate Melts and Carbonatites. Reviews in Mineralogy and Geochemistry, 2013. 75(1): p. 289-322.3          Solopova, Dubrovinsky, Spivak, Litvin, and Dubrovinskaia, Melting and decomposition of MgCO3 at pressures up to 84 GPa. Physics and Chemistry of Minerals, 2014. 42(1): p. 73-81.4          Müller, Koch-Müller, Rhede, Wilke, and Wirth, Melting relations in the system CaCO3-MgCO3 at 6 GPa. American Mineralogist, 2017. 102(12): p. 2440-2449.5          Ellis and Wyllie, Carbonation, hydration, and melting relations in the system MgO-H2O-CO2 at pressures up to 100 kbar. American Mineralogist, 1979. 64(1-2): p. 32-40.6          Girnis, Bulatov, Brey, Gerdes, and Höfer, Trace element partitioning between mantle minerals and silico-carbonate melts at 6–12GPa and applications to mantle metasomatism and kimberlite genesis. Lithos, 2013. 160-161: p. 183-200.7          Buob, Experiments on CaCO3-MgCO3 solid solutions at high pressure and temperature. American Mineralogist, 2006. 91(2-3): p. 435-440.
Advancing slope stability computations in distributed hydrologic computations
Authors: Bonomelli Riccardo , Pilotti Marco
Published: February 2023

Settlements in mountain areas can be endangered by the occurrence of landslides usually triggered by excessive rainfall events in the catchment. A major issue with hazard mapping is the identification of unstable zones. The Infinite Slope (IS) model coupled with suitable hydrologic hypothesis has frequently been used to assess soil instability at the catchment scale, usually overestimating instability. Moreover, its fundamental assumption that neglects all boundary contributions to equilibrium or motion may become less and less viable with the growing resolution of the elevation data nowadays available. To relax this assumption along the slope length we adopt the Janbu’s method applied in a progressive manner. Dividing a generic slope into blocks, the Janbu’s method is applied first to a single block (the bottom one) then to the collection of the first and second block, then to the first three and so on, up to the point in which the whole slope is considered. Multiple slopes can be analysed in this way, thus covering the entire catchment with computational costs comparable to the IS approach. Using this method, a slope can turn out as globally unstable due to the action of single blocks located along its length. The method is validated against simple slopes whose stability has already been studied in the geotechnical literature. Transient relative soil saturation at each cell is computed adopting a distributed hydrologic model coupled with the described slope stability model. The hydrologic model uses a raster representation of the watershed elevation that is pre-processed to compute a Space-Filling Drainage Network and a channel network upon which the Green-Ampt method together with the Darcy’s equation are solved using suction, porosity, saturated permeability, and soil depth as parameters. A kinematic wave approach has been used to predict runoff and subsurface flows. Validation of the slope stability model shows that the Factor of Safety (FS) computed using the progressive Janbu’s method converges to the predictions of more rigorous methods like Finite Elements method within reasonable accuracy on different saturation conditions. Application of the whole modelling chain to a watershed test case show less unstable areas with respect to the predictions of the IS model. This procedure can be applied to entire catchments using rainfall and soil characteristics as boundary conditions and parameters to output the stability of all the cells present in the domain as a function of time. The proposed approach may suggest a more rigorous way to compute the FS with respect to the IS model in catchment scale applications.
Simultaneous eddy flux monitoring of 10 greenhouse gases and air pollutants with a single instrument
Authors: Hundt Morten , Brunner Marco , Aseev Oleg
Published: February 2023

Monitoring of trace gas fluxes and greenhouse gas fluxes is key to understand the interaction between atmosphere, plants, and soil and therefore to improving our understanding of the climate system in general.The complex flux systems require measurement of many different inert and reactive trace gases and greenhouse gases simultaneously to obtain a complete budget. This is especially the case in urban environments where both biogenic and anthropogenic sources and sinks play a role.The eddy covariance (eddy flux) technique is often used to determine fluxes of the gases in question. Until recently, however, the monitoring was usually limited to only a few gases per measurement device making the technique complex and expensive but providing only a limited picture. MIRO Analytical has developed a novel multicompound gas analyzer that can monitor up to 10 air pollutants (CO, NO, NO2, O3, SO2 and NH3) and greenhouse gases (CO2, N2O, H2O and CH4) simultaneously with the high time resolution necessary for eddy-covariance flux measurements. The compact system combines several mid-infrared lasers (QCLs) providing outstanding precision, selectivity and accuracy for the gas measurements.In our contribution we will introduce the measurement technique and will demonstrate application examples of this all-in-one atmospheric flux monitor. The system will be compared to alternative devices in parallel measurements and results of long-term observations and shorter campaigns will be presented.
3D Quasidynamic cycles accelerated using Hierarchical Matrices: Role of complex fault geometry
Authors: Cheng Jinhui , Almakari Michelle , Peruzzo Carlo , Lecampion Brice , Bhat Harsha
Published: February 2023

Fault systems have geometrically complex structures in nature, such as stepovers, branches, and roughness. Both geological and geophysical studies indicate that the fault geometry complexities can have a first order effect on spatio-temporally complex slip dynamics. However, a vast majority of models of slip dynamics are conducted on planar faults due to algorithmic limitations. We develop a 3D quasi-dynamic slip dynamics model with Hierarchical matrices to overcome this restriction. The calculation of elastic response due to slip is a matrix-vector multiplication, which can be accelerated by using hierarchical matrices and easily multi-threaded. The computational complexity is reduced from the order of O(N2) to O(NlogN). We cross-validate our code with the SCEC run SEAS benchmark/validation exercise. With this approach, we then explore the role of fundamental geometry complexities and realistic fault geometry on slip dynamics. We also plan to analyse synthetic signals and compare with seismological and geodetic observations.
Statistical analysis of extreme waves from satellite altimetry from 2002 to 202
Authors: Laloue Alice , Ghantous Malek , Faugere Yannice
Published: February 2023

Statistical analysis of extreme wave heights over the globe requires long and sufficiently resolved time series of data that have so far only been available in model reanalyses. In recent years, time series of altimetry observations that allow us to perform this study have become available. Global maps of extreme significant wave heights were produced over 2002-2020 using a level-4 gridded CMEMS product merging CMEMS significant wave height along-track measurements from 7 altimetric satellites. ERA5 reanalysis data, developed by the ECMWF and available from 1950 onwards, were used as a means of comparison. The extreme significant wave heights were first analyzed using quantiles such as the 95th percentiles. A second approach based on the Peak-Over-Threshold and the Generalized Pareto Distribution allowed us to estimate 100-year significant wave heights. Global maps obtained on CMEMS altimetric were eventually compared with maps obtained on ERA5 reanalysis. Extreme wave heights estimated with both approaches show a spatial structure similar to the maxima in the climatological mean but with greater magnitude. Largest trends are exhibited in the Southern Ocean, where the wave heights tend to increase significantly in all results, while the North Atlantic and North Pacific exhibit more complex patterns of trends.
When do plant hydraulics matter in ecosystem modelling?
Authors: Paschalis Athanasios , Fatichi Simone , Sabot Manon , de Kauwe Martin
Published: February 2023

 The dynamics of the ascent of water from the soil to the leaves of vascular plants determine ecosystem responses to environmental forcing and their recovery from periods of water stress. Recently several models that describe the dynamics of plant hydraulics have been proposed. In this study we introduce four different configurations of a plant hydraulics model in an existing terrestrial biosphere model T&C. The model configurations in increasing order of complexity introduce the basics of the cohesion-tension theory, plant water storage dynamics and long-term damage and repair of the plant's water conducting system. Using the model configurations at six case studies spanning semi-arid to tropical ecosystems we quantify how plant hydraulics can modulate overall ecosystem responses to environmental forcing. As droughts develop, models with plant hydraulics predict a slower onset of plant water stress and can reproduce diurnal patterns of water and carbon fluxes that models that incorporate empirical stomatal conductance only cannot capture. However, when the complex variability of the environmental forcing (i.e., observed hourly meteorological forcing driving the models) is considered, plant hydraulics alone cannot significantly improve model performance. Models that only have simple empirical stomatal conductance models can adequately capture most of the variability of the observed ecosystem responses without explicitly simulating plant hydraulics. Most of the time, the gain from introducing plant hydraulics in ecosystem modelling is limited compared to the possible model improvements from correct representation of other processes such as plant phenology. Nevertheless, during periods of water stress, only models that explicitly simulate plant hydraulics can reproduce observed ecosystem responses to stress and the dynamics of ecosystem recovery. Finally, sensitivity analyses highlight that accurately modelling plant hydraulics relies on good knowledge of plant hydraulics traits, particularly at the leaf level, as stomata are usually the hydraulic bottleneck in the water flow from the soil to the atmosphere.
Seven years of UV camera-based SO2 flux observations at Mount Etna
Authors: Lo Bue Trisciuzzi Giovanni , Aiuppa Alessandro , Bitetto Marcello , Delle Donne Dario , Coltelli Mauro , Pecora Emilio , Alparone Salvatore , Ganci Gaetana
Published: February 2023

Volcanic SO2 flux observations are relevant to understanding the magmatic processes that occur within the shallower portions of magmatic plumbing systems, and the mechanisms governing transition from open-vent quiescent degassing to explosive activity. Here, we review a SO2 flux dataset acquired at Mt. Etna volcano from a permanent UV camera system during more than 7 years of observations, from June 2015 to December 2022. Our fully automated UV camera system, housed in the Montagnola INGV-OE hut, is designed to spatially resolve SO2 emissions from the southern portion (SEC + Central Craters) of the summit craters’ terrace. The observed period encompasses a variety of eruptive phenomena, including the Voragine Crater (VOR) paroxysmal episodes in 2015-2016, several effusive and lateral eruptions (including the late 2019 “Christmas eruption”) and the two most recent paroxysmal sequences of the South-East Crater (SEC) in December 2020/April 2021 and May/October 2021. We find large temporal variations in the SO2 flux in response to changes in volcanic activity style and vigour. Our results, in particular, demonstrate a clear acceleration in SO2 degassing during effusive eruptions and paroxysmal episodes, relative to non-eruptive (quiescent) periods. Escalating SO2 flux (>5000 t/d) is especially relevant prior (circa 1 month before) onset of the December 2020/April 2021 SEC paroxysmal sequence, whilst reduced degassing (<3000 tons/d) characterises the quiescent phases in between the paroxysmal sequences. This 2020-2021 paroxysmal sequences is characterised in more detail by complementing gas observations with volcanic tremor results and thermal output records (both ground- and satellite-based). Results are interpreted in view of a S degassing model lead that explain elevated SO2 fluxes as caused by augmenting rate of magma transport into the shallow (< 5 km) Etna’s plumbing system.
Scaling up a Sentinel 1 change detection pipeline using the Julia programming language
Authors: Gans Fabian , Cremer Felix
Published: February 2023

With the amount of high resolution earth observation data available it is not feasible anymore to do all analysis on local computers or even local cluster systems. To achieve high performance for out-of-memory datasets we develop the YAXArrays.jl package in the Julia programming language. YAXArrays.jl provides both an abstraction over chunked n-dimensional arrays with labelled axes and efficient multi-threaded and multi-process computation on these arrays.
In this contribution we would like to present the lessons we learned from scaling an analysis of high resolution Sentinel-1 time series
data. By bringing a Sentinel-1 change detection use case which has been performed on a small local area of interest to a whole region we test the ease and performance of distributed computing on the European Open Science Cloud (EOSC) in Julia.
Geological record of megatsunamis in Mediterranean deep sea sediments
Authors: Polonia Alina , Nelson Hans C. , Vaiani Stefano C. , Colizza Ester , Gasparotto Giorgio , Giorgetti Giulia , Bonetti Carla , Gasperini Luca
Published: February 2023

The Mediterranean Sea hosts two subduction systems along the convergent Africa-Eurasia plate boundary that have produced strong ground shaking and generated tsunamis.  Based on historical descriptions and sedimentary records, one of these events, in 365 CE, impacted a broad geographical area qualifying it as a ‘megatsunami’. Understanding how megatsunamis are produced, and where they are more likely, requires a better understanding of the different secondary processes linked to these events such as massive slope failures, multiple turbidity current generation, and basin seiching.An extensive collection of cores located in distal and disconnected deep basins, identified turbidites which were analyzed using granulometry, elemental (XRF), micropaleontological, and geochemical data in order to define sedimentary processes during the propagation of the CE 365 Crete megatsunami. The deposit contains a volume of detrital siliciclastic and biogenic components as large as 800 km3. The sediment from the European and African margins was remobilized and transported by tsunamis to abyssal depositional sites and isolated basins during the catastrophic event. The resedimented deposits, when viewed across multiple geomorphological locations of the marine depositional sites (canyon mouth, abyssal, isolated higher basin), demonstrate a complex sequence of processes triggered by the megatsunami wave propagation. The tsunamis produced multiple far-field slope failures that resulted in stacked basal turbidites. It also caused transport of continent-derived organic carbon and deposition over basal turbidites and into isolated basins of the deep ocean. The composition of sediment in isolated basins suggests their deposition by large-scale sheet like flows similar to what has been caused by the Tohoku earthquake associated tsunamis. A local turbidite bed at the base of the deposit in isolated basins on the accretionary wedge indicates that sediment remobilization from basin walls was possibly related to the passage of the tsunami in deep water. When the tsunami wave hit the continental margins in Italy and Africa, it triggered turbidity currents on the slopes, which resulted in the stacked basal sand and silt units of the resedimented deposit. The analyses of geophysical data shows the presence of additional deposits of a similar nature from older layers with an age of about 14 and 40-50 Ka. This is significant for rectifying and resolving where risk is greatest and how cross-basin tsunamis are generated.
Typomorphic mineralogical characteristics of pyrrhotite in Jiama Cu polymetallic deposit, Tibet, and its geological significance
Authors: Yang Yang
Published: February 2023

The Jiama deposit is located in the eastern part of Gangdise metallogenic belt, and is one of the largest copper polymetallic deposits in Tibet. Pyrrhotite is one of the most common metallic minerals of the Jiama deposit.Its typomorphic characteristics not only reflect its formation environment but also indicate its formation mechanism and deposit genesis. In this paper, pyrrhotite samples from different lithologies were collected, and the morphology, composition and structure of pyrrhotite were analyzed by means of mineralogy, X-ray diffraction and electron microprobe analysis. The study shows that pyrrhotite of the Jiama deposit is mainly distributed in the skarn and hornfels, which are far away from the center of the porphyry intrusion. The powder X-ray diffraction curves and cell parameters of pyrrhotite show that the pyrrhotite in the skarn is mainly high-temperature hexagonal pyrrhotite. The pyrrhotite in the hornfels is a mixture like associated body of high-temperature hexagonal pyrrhotite and low-temperature monoclinic pyrrhotite, with the monoclinic pyrrhotite being dominant. The results of electron microprobe analysis of pyrrhotite in skarn and hornfels show that the content of Fe in pyrrhotite of skarn is 60.09%~60.71%, averaging 60.38%, and the content of S is 38.18%~38.69%, averaging 38.35%, with the corresponding chemical formula being Fe8S9~Fe10S11. At the same time, the content of Fe in pyrrhotite of hornfels is 59.05%~59.57%, averaging 59.10%, and the content of S is 39.28%~39.95%, averaging 39.59%, with the corresponding chemical formula being Fe5S6~Fe7S8. Based on the above mineralogical characteristics, the author hold that the precipitation mechanism of pyrrhotite in the deposit is as follows: the hot magma surged and interacted with the carbonate and clasolite formation, and the addition of atmospheric water caused the ore-forming fluid to quickly cool down in the hornfels, forming associated body of high-temperature hexagonal pyrrhotite and low temperature monoclinic pyrrhotite. At the same time, a large number of ore-bearing hydrothermal fluids formed and filled in favorable ore-forming space (mainly interlayer fracture zone) for precipitation and mineralization, forming skarn orebodies; the fluid then experienced a slow cooling in the skarn ore segment to form a high temperature hexagonal pyrrhotite. Based on geological characteristics of the deposit and geochemical characteristics of related elements, it is concluded that the Jiama deposit type is of the porphyry-skarn type.
Extraction of solar forcing signatures in ground magnetometer data from sub-auroral regions
Authors: Haberle Veronika , Marchaudon Aurélie , Chambodut Aude , Blelly Pierre-Louis
Published: February 2023

In order to monitor space weather events and their impacts, ground magnetic field data has proven to be a long-lasting and powerful source of information. For the determination of the impact of solar events it is essential to extract their signatures from the magnetic field signal. However, as the geomagnetic field is a superposition of sources that cover a broad amplitude and frequency spectrum, it is not trivial to isolate storm signatures. The major source is the intrinsically produced magnetic field that changes within years and is called the secular variation. In sub-auroral regions, it is well known that during times of minimum solar forcing the solar quiet current system induces smooth daily variations with strong dependency on season and local time.In this work we apply signal filtering techniques on time-series magnetic data from ground observatories in sub-auroral regions to extract the various sources. We then use these filter outputs to inspect their dependency and sensitivity to solar forcing. Additionally, statistical parameters are sought after to determine storm signatures.
Atmospheric response to Tropical Instability Waves in high-resolution coupled NextGEMS simulations
Authors: Jungclaus Johann , Putrasahan Dian , Bastin Swantje , Specht Mia-Sophie
Published: February 2023

Oceanic Tropical Instability Waves (TIW) are characterized by westward propagating cusp-shaped sea surface temperature (SST) patterns with sharp fronts and strong lateral SST gradients. TIWs impact local winds and ocean atmosphere heat fluxes and these changes consequently feed back onto the ocean.Previous studies have used stand-alone atmosphere or regional coupled ocean-atmosphere models at moderate to high resolution.  The new global simulations, which are run at km-scale resolution in both ocean and atmosphere in the framework of the H2020 NextGEMS project, offer new opportunities to study local, regional, and remote effects of TIW-related ocean-atmosphere interactions.Using the coupled ICON-a/ICON-o “Sapphire” simulations (Hohenegger et al., 2023), we compare the ocean-atmosphere coupling in the Pacific and Atlantic basin and investigate the interaction of TIWs with the Intertropical Convergence Zone. In the western tropical Atlantic, north of the Equator, TIW induced SST patterns also interact with North Brazil Current eddies and we investigate the effects of pronounced fronts on ocean-atmosphere heat fluxes.Hohenegger, C. at al., 2023: ICON-Sapphire: simulating the components of the Earth System and their interactions at kilometer and subkilometer scales, Geoscientific Model Development, https://doi.org/10.5194/gmd-2022-171.