bluuebunny/crossref_metadata_2025 huggingface dataset:
Heterogeneous deformation across the Papaku fault, Hikurangi accretionary prism 
Authors: Kühn Rebecca , Greve Annika , Kilian Rüdiger , Mizera Marcel , Stipp Michael
Published: March 2022

At the Hikurangi convergent margin the Pacific plate is subducted westward beneath the Australian plate. This margin has been the location of major earthquakes as well as slow slip events related to the ongoing subduction. Drill site U1518 which was drilled during IODP Expedition 375, 73 km offshore Gisborne (New Zealand), targeted the Papaku fault, a splay fault of the major decollement in sediments of the frontal accretionary prism. We selected samples from the mostly hemipelagic, weakly consolidated mudstones in the fault zone, as well as from hangingwall and footwall. In order to investigate localized and distributed deformation in the fault zone, we analysed composition, microstructure and crystallographic preferred orientation (CPO). For that we applied µXRF measurements and optical microscopy, as well as synchrotron texture analysis at DESY in Hamburg.

The samples from hanging- and footwall sediments show a relatively homogeneous microstructure with local compositional layering. While CPO strength in the hangingwall is slightly increasing with depth for all analysed clay mineral phases, the CPO in the footwall samples is in general lower and does not show a clear trend with depth. This might be interpreted as different deformation histories in hangingwall and footwall which is in accordance with previous studies. Fault zone samples show a variety of microstructures, such as mingling of different sedimentary components, locally overprinted by microfaults. CPO strength in the faulted sediments is also variable, with zones showing strong alignment of phyllosilicates and zones showing weak alignment of phyllosilicates. Variations in CPO and variable distribution of sedimentary components indicate a heterogeneous deformation within the fault zone which might be due to local compositional variations.
Climate change impact on rain, snow and glacier melt components of streamflow for the river Rhine: synthesis of a model experiment and relevance for water use 
Authors: Stahl Kerstin , Weiler Markus , Van Tiel Marit , Kohn Irene , Haensler Andreas , Freudiger Daphne , Seibert Jan , Moretti Greta , Gerlinger Kai
Published: March 2022

Streamflow of the river Rhine and its tributaries consists of rain, snowmelt and glacier ice melt components. The amounts of these components have already changed in the past years due to climate warming. Hydrological modelling until the year 2100 was carried out for the Rhine catchment using an ensemble of downscaled and bias-corrected climate projections and a chain of hydrological models considering cryosphere changes. The modelled daily streamflow components provide unique insight into the hydrological processes of a warmer future at different spatial and temporal scales down to individual events. In the Rhine basin, projected precipitation for the RCP8.5suggest wetter winters and drier summers, but annual net precipitation change differs in the up- and downstream regions with a net increase projected only in the lower basin. The model experiments suggest that the rain component of streamflow will dominate the seasonal variability in the future more than in the past. Snow will provide less seasonal water storage and melt earlier in winter and spring. Glaciers will continue their retreat with differences among individual glaciers and the ice melt component in the main river Rhine is projected to retreat fast with almost no ice melt component left at the end of the century. As a consequence, in particular low flows in downstream reaches will exacerbate due to the lack of buffering snow and ice melt; esp. during hot summer drought years. This change will affect environmental flows, water use for energy production, navigation and other water uses, changes of which can be estimated from the modelled scenarios. Overall, streamflow variability and extremes will increase. Despite propagated uncertainties from a range in the downscaled and bias-corrected climate model input, the projected changes are substantial and are a clear mandate to reconsider water uses and enhance river protection goals.
An interactive Greenland Ice Sheet in EC-Earth3: Model Evaluation
Authors: S. Madsen Marianne , Lindpointner Laurent , Yang Shuting , Rodehacke Christian
Published: March 2022

In order to capture the complex interactions and feedbacks between large ice sheets and the climate system, two-way coupled climate – ice sheet models are needed, which allow a dynamical ice sheet to be influenced by the climate state and vice versa. Here, we present the coupled model system EC-Earth3-GrIS, consisting of the global climate model EC-Earth3 two-way coupled to the PISM Parallel Ice Sheet Model for Greenland. The ice sheet model receives surface forcing in the form of surface mass balance (SMB) and surface temperature and returns ice sheet topography, and fluxes of basal melt and ice discharge to EC-Earth3. Two methods for obtaining the SMB are tested: (1) the SMB is directly calculated in EC-Earth3 at a horizontal resolution of ~80 km and regridded to the PISM ice sheet model at 5 km horizontal resolution; (2) a downscaled measure of the SMB at the resolution of the ice sheet model is calculated using the Copenhagen Ice Snow Surface Energy Balance Model (CISSEMBEL) forced with the 6-hourly surface fluxes from EC-Earth3. The implications of the downscaling of the SMB and the influence on the ice sheet initial state are evaluated, and the state of the Greenland Ice Sheet in the EC-Earth3 preindustrial climate is assessed.    
A numerical model for CO2 gas migration in a fault zone.
Authors: Romano Valentina , Bigi Sabina , Park Heeho , Valocchi Albert J. , Hyman Jeffrey De'Haven , Karra Satish , Nole Michael , Hammond Glenn , Proietti Giampaolo , Battaglia Maurizio
Published: March 2022

In a geological CO2 storage site, the main migration pathways in case of leakage would be compromised boreholes or gas permeable faults or fractures. In this work we propose a modeling workflow based on detailed field data acquired on a fault exposed in the Roman Valley Quarry (Majella Mountain, Italy), to simulate the three-dimensional migration of gas CO2 in the fault zone. The numerical modeling is performed using the open-source multiphase flow simulator PFLOTRAN. This study provides a new methodology to characterize the hydraulic behavior of a fault including all its components, the core and the damage zone, capturing in detail the impact of the fault zone architecture to the migration of CO2. Simulation test results point out the robustness of the modeling approach, highlighting its strong predictive power, and show how most of the gas migrates through the high permeable footwall damage zone, where the injection occurs, whereas some of the gas also migrates through the hanging wall damage zone and the fault core. The buildup of gas pressure in the vicinity of the injection wells demonstrates the need of increasingly accurate modeling of the injection conditions to avoid possible faults reactivation and CO2 leakage. While the technique presented here is applied to a case scenario on carbonate rocks, the proposed methodology can be extended to other geological scenarios, by the appropriate calibration of the geometric and petrophysical parameters of fractures and host rock, to understand the conditions under which faults can promote fluid flow from a reservoir and mitigate the risk of CO2 migration via faults.
Regional geomagnetic field model over the area comprising the South Atlantic Anomaly
Authors: Campuzano Saioa A. , De Santis Angelo , Pavón-Carrasco F. Javier
Published: March 2022

Taking advantage of the Swarm three-satellite magnetic field mission by ESA, launched on 22 November 2013 and still orbiting, and ground observatory magnetic data, we determine a spatiotemporal regional model for the geomagnetic field using the R-SCHA technique over the area comprising the South Atlantic Anomaly (SAA). The SAA is the region above the South Atlantic and South America where the geomagnetic field intensity is much lower than expected by a simple dipolar field. Its origin is deep in the outer core and is likely due to a reverse magnetic flux area that has been increasing in the last four centuries. On the basis of this model, we observe 1) the recent evolution of the anomaly from 2014 up to date, with a focus on its “tails” towards South Africa and West Pacific, 2) some features that can be related to important properties of the main geomagnetic field, such as its secular variation and the occurrence of geomagnetic jerks.
Coarse woody debris density and elemental components by decay classes for ten tree species in Croatia
Authors: Bitunjac Doroteja , Ostrogović Sever Maša Zorana , Sever Krunoslav , Marjanović Hrvoje
Published: March 2022

Coarse woody debris (CWD), aside its contribution to forest ecosystem productivity and biodiversity, has a significant role in nutrient cycling and carbon storage. Still, CWD chemical features, as well as its density, are less studied in comparison to other plant traits. This is evident from the statistics of the most recent version 5 of TRY Plant Trait Database where CWD traits are underrepresented. Nevertheless, also due to the carbon (C) accounting requirements under UNFCCC and EU regulations, where dead wood (DW) is recognized as one of five mandatory C pools in forest ecosystems, interest in CWD has been increasing. The aim of this research was to provide national DW biomass conversion factors, i.e. dead wood densities (DWD) and C concentrations, which can be used for reporting on C stocks in DW pool. We hypothesize that there are differences in DW biomass conversion factors with respect to tree species group (ring-porous, diffuse-porous, non-porous) and biogeographical region. Additionally, we explored the content of N, K, Ca, P, Mg mineral macronutrients in CWD of different decay classes and tree species. 

The research was conducted on ten forest tree species that represent main forest ecosystems in Croatia located in three biogeographical regions, i.e. Continental, Alpine and Mediterranean. In the field, stem discs were sampled from lying CWD, with diameter between 5 and 30 cm, that was categorized into five decay classes, from 0 (raw wood) to 4 (very decayed dead wood). In total, we collected 446 CWD samples evenly distributed between tree species and decay classes. All samples were analysed for density, C and N content, with selected 165 samples analysed further on K, Ca, P, Mg content. Overall, DWD, as expected, showed decreasing trend with respect to decay class, while for C, N and mineral macronutrients no trend regarding decay classes was observed. For each tree species group, DWDs by decay classes were compared between different biogeographical regions. In ring-porous species a significant difference was observed in DWD between samples collected in Continental and Mediterranean biogeographical region for decay classes 0-2, while in non-porous species DWD between samples collected in Alpine and Mediterranean biogeographical region were significantly different for decay classes 2-4. Results on C, N and mineral macronutrients were were compared with those published in TRY database and other available sources.
Numerical Tsunami Inundation Modeling in Ambon City, Indonesia for Potential Earthquake and Landslide at Ambon bay
Authors: Yatimantoro Tatok , Harvan Muhammad , Anugrah Suci Dewi , Daryono Daryono , Prayitno Bambang Setiyo , Adi Suko Prayitno
Published: March 2022

A tsunami numerical inundation modeling in the Ambon city was developed by considering large earthquakes along the Ambon bay strike-slip fault and triggering submarine landslide as the tsunami source. 
The simulation was conducted using Comcot (Cornell Multi-grid Coupled Tsunami model) with a nested grid system in the spherical coordinate system. The four different spatial grid sizes of 60 (layer 1), 15 (layer 2), 3.75 (layer 3), and 0.9375 (layer 4) arc-sec were used in the computation. The linear shallow-water theory with bottom friction was applied for layers 1 -3, meanwhile, layer 4 used the non-linear shallow-water theory with manning roughness coefficient and detail bathymetry data. 
The single segmentation of earthquake scenarios with magnitudes Mw 7.2 was assumed. The earthquake then triggers submarine landslides in some areas around Ambon city. The landslide area was approached by Peak Ground Acceleration (PGA) value and historical data.
The results showed that in Ambon city the first tsunami wave arrived 18 min after the earthquake with a maximum flow depth of 7.4 m and inundation distance around 1.2 km. These results show that Ambon city has a risk of tsunami threat from earthquakes and submarine landslides. Therefore, it is necessary the tsunami hazard preparedness by the government and communities.
The Neotethyan Arabian necking zone exposed at the SE Oman mountains: field evidence and consequences
Authors: Ducoux Maxime , Masini Emmanuel , Scharf Andreas , Calassou Sylvain
Published: March 2022

The Late Cretaceous Oman Mountains are generally assumed to result from obduction followed by the inversion of the mid-Permian- to Triassic Neotethyan rifted margin. However, the key rift-related crustal features, such as a necking zone or hyper-extended rift domains remain inferred and poorly described so far. In this study, we investigate the tectono-stratigraphic record of the eastern part of the Oman Mountains where the exposed Tonian (Neoproterozoic) crystalline basement outcrops together with the pre- to syn-obduction sedimentary record in the Ja’alan massif area. The description of these units together with subsurface data enables to describe the former Arabian necking zone. The Ja’alan massif itself and the Arabian platform to the southwest represent the former proximal margin domain. It is characterized by the eroded basement sealed by post-obduction continental to shallow marine sediments. In contrast, the north-eastern side of the massif is flanked by Permian-Mesozoic deep marine post-rift sediments (Batain Group) equivalent to the Hawasina thrust sheet in the Oman Mountains. These two endmember paleogeographic units are separated by a major N20 dipping top-to-the-NE normal fault with dip-slip kinematics (slikensides with striae, S/C-fabric). The damage zone of this fault is characterized by a cataclastic and a gouges fault zone, overlain by slope facies with syn-kinematic polymictic mega-breccias reworking the adjacent basement. The breccias are grading finer upwards, contain conglomerate and sandstone interbeds interpreted as to slope-environment turbiditic channel deposits. This exhumation and rift-related record is unconformably covered by the post-obduction sequence affected by a late Cenozoic E/W-directed low-amplitude shortening. The intensity of shortening is increasing toward the NW leading to reactivate the Arabian Necking zone as a ramp for the Hawasina thrust system. Based on these observations, we propose a new geodynamic model showing that the final stage of the obduction result from the inversion of the former Arabian necking zone with significant impacts on the evaluation of (1) the shortening rates accommodated and (2) the former architecture of the Arabian Tethyan rifted margin. As the belt never recorded a mature continent-continent collision, we think that the Oman study case could significantly help to investigate the dynamics of hyper-extended rifted margins inversion at an early orogenic stage.
Numerical models to evaluate the potential effects of new port realization on coastal marine ecosystems 
Authors: Bonamano Simone , Federico Ivan , Mancini Emanuele , Causio Salvatore , Piermattei Viviana , Piazzolla Daniele , Scanu Sergio , Jansen Eric , Coppini Giovanni , Fersini Giorgio , Marcelli Marco
Published: March 2022

The potential effects of anthropic pressures on the coastal marine environment are difficult to predict due to the high spatial and temporal variability of the physical and biological processes occurring in the coastal area. To overcome this issue, an innovative coastal observing and modelling system has been implemented along the Latium coast (Italy). The core of the modelling suite is composed of the unstructured-grid hydrodynamic SHYFEM and wave WW3 models to allow to compute the temperature, salinity, current velocity, water levels and wave parameters, seamlessly from the open sea to the coastal waters. The hydrodynamic and wave results were then used within process-oriented models (such as XBEACH, PTM, Leeway Lagrangian particles models) to analyse morphological changes, sediment dynamics and pollutant dispersion in the coastal, riverine and near-port areas.

In this work, the modelling suite was used to investigate the potential effects on the soft-bottom benthic communities due to the realization of the new port of Fiumicino, located in the coastal zone affected by the Tiber river dynamic. The coastal dynamic processes along the study area were simulated using different weather conditions, before and after the realization of the new harbour. Hydrodynamic and wave model performance was evaluated using in-situ and remote sensing observations carried out by high-resolution satellite imageries and traditional and innovative in-situ platforms. Finally, the model results were compared with the abundance and composition of the benthic community that was analysed in 25 stations, between 2 and 30 m depth.
Solubility of water in peridotite liquids and the formation of steam atmospheres on rocky planets
Authors: Sossi Paolo , Tollan Peter , Badro James , Bower Dan
Published: March 2022

Atmospheres are products of time-integrated mass exchange between the surface of a planet and its interior. On Earth, the most significant of these events occurred when it existed in a magma ocean state, producing its earliest atmosphere. During this stage, both steam- and carbon-rich atmospheres may have been generated in equilibrium with a magma ocean [1, 2]. However, the nature of Earth’s early atmosphere, and those around other rocky planets, remains unclear for lack of constraints on the solubility of major atmophile elements in liquids of appropriate composition.

Here we determine the solubility of water in 14 peridotite liquids synthesised in a laser-heated aerodynamic levitation furnace [2]. We explore oxygen fugacities (fO2) between -1.5 and +6.4 log units relative to the iron-wüstite buffer at constant temperature (1900±50 °C) and total pressure (1 bar). The resulting fH2O ranged from nominally 0 to ~0.028 bar and fH2 from 0 to ~0.065 bar. The total H2O contents were determined by FTIR spectroscopy of polished thick sections by examining the intensity of the absorption band at 3550 cm-1 and applying the Beer-Lambert law.

We find that the mole fraction of dissolved water in the liquid is proportional to (fH2O)0.5, attesting to its dissolution as OH-. The solubility coefficient fit to the data yields a value of ~500 ppm/bar0.5, roughly 30 % lower than that determined for basaltic liquids at 1350 °C and 1 bar [3]. Therefore, more Mg-rich compositions and/or higher temperatures result in a significant decrease of water solubility in silicate melts. While the solubility of water remains high relative to that of CO2, we hypothesise that steam atmospheres may form under oxidising conditions, provided sufficiently high temperatures and H/C ratios in terrestrial planets prevail.

[1] Gaillard, F. et al. (2022), Earth Planet. Sci. Lett., 577, 117255. [2] Sossi, P.A. et al. (2020), Science Adv., 6, eabd1387. [3] Newcombe, M.E. et al., (2017), Geochim. Cosmochim. Acta, 200, 330-352.
Shannon and Tsallis entropy results for particle resting times and jump lengths in river bedload 
Authors: Pilbala Ashkan , Tosato Luca , Fraccarollo Luigi , Bahmanpouri Farhad , Moramarco Tommaso
Published: March 2022

Sediment transport in rivers consists, at a moderate discharge stage, of individual grains that undergo a series of step movements and rest periods (bedload). In this study, we exploited available data representing resting time and jump length of particles involved in bedload processes. Following the entropy approach based on Shannon and Tsallis theories, we got formal probability functions describing the distribution of the above-mentioned kinematic quantities. Finally, accepting the Einstein assumptions and exploiting the experimental data, we found the values of the constants involved in the entropy functions and complete the analysis. A comparison between experimental and theoretical distributions is showing encouraging matches.

An indirect, but quite relevant, way to prove the validity of the obtained probability distribution, is worked out by looking at the dispersion of traced grains, originally located in well-bordered pillows at different depths within the bed. The application of a stochastic model able to move the grains of the bed with prescribed frequencies in space and time allowed us to further appraise a good behavior of the entropy-based distributions versus the experimental ones.  

Future directions of this research would address the important goal nested in the detection of river flow with or without bedload, by using entropy information based on the measurement of velocity field and/or flow depths over cross-sections.
Physical constraints and magma dynamics of Mt. Etna rift systems
Authors: Giacomoni Pier Paolo , Masotta Matteo , Costa Simone , Lanzafame Gabriele , Coltorti Massimo
Published: March 2022

 

Mt. Etna features an articulated plumbing system characterized by a central open-conduit, culminating with the persistent degassing summit craters, three rift-related lateral systems (S-Rift, NE Rift and W Rift) and the eccentric feeding system, characterized by disperse monogenetic cones.

In the last twenty years, most the eruptive activity occurred at the summit central craters and by consequence most of the recent petrological studies focused on the parametrization of the central open-conduit system. In this study, we move the focus to the NE Rift system, whose last activity dates back to the 2002-2003 eruption. Rift-related events are potentially more dangerous since they are often accompanied by energetic precursor seismicity and increase the probability of lava effusion at low altitude where towns and infrastructures are concentrated. Samples from this last eruption were examined and the new chemical data integrated with a comprehensive whole rock and mineral chemistry dataset from pre-historical and historical events.

Textural observations of the NE Rift products highlight a greater variability compared to magmas erupted from the central craters, in spite of a comparable mineral assemblage made of Ol, Cpx, Plg and Ti-Mt. High and low porphyritic lavas coexist in the same event and appear frequently mingled. Similarly, whole-rock composition varies from hawaiite-trachybasalt to benmoreite, in contrast with the rather homogenous trachybasaltic composition of magmas erupted from the central craters. Plagioclase phenocrysts show partially resorbed rims associated with an increase in An content or alternatively, alignments of melt inclusions near the crystal rim, related to a decrease in An content.

Thermo-barometric estimates based on Ol-Liq and Cpx-liq equilibria suggest that most of Ol and Cpx phenocrysts equilibrated at temperature comprised between 1140 to 1000 °C and pressure ranging from 10 to 2 Kbar, with a remarkably higher DT/DP with respect to magmas erupted at the central craters. This suggests a magma crustal ponding zone between 4 and 2 kbar. These results have been integrated by thermodynamic modelling through the energy-constrained model Magma Chamber Simulator able to compute the evolution of the magma via fractional crystallization in a polybaric and polythermal volcanic plumbing system. Results highlights that fractionation occur along the Ol-Cpx-Plag liquid line of descent in a range of pressure equivalent to those determined by the crystal-melt geobarometry.
Information flow within the magnetosphere-ionosphere system: insights from ensemble-based transfer entropy
Authors: Stumpo Mirko , Consolini Giuseppe , Benella Simone , Alberti Tommaso
Published: March 2022

When the interplanetary magnetic field is characterized by nearly-southward conditions, the near-Earth magnetospheric environment and, specifically, the plasma circulation and the magnetospheric-ionospheric current systems undergo to some dynamical changes to dissipate the excess of energy-momentum and mass transfer from interplanetary medium to the magnetosphere. Geomagnetic storms and magnetospheric substorms are the macroscopic manifestation of such a response and their relation is one of the critical issues of the magnetospheric dynamics. In this framework, a very old and widely debated topic is the storm-substorm relations, such as for instance the role of substorms in developing a storms. In recent years, some novel methods developed in the ambit of the information theory, such us the transfer entropy, have been applied to unveil the directionality of the information flow between storms and substorms (De Michelis et al., 2011, Stumpo et al, 2020). However, these results have been partially criticised suggesting that there is not a clear net transfer of information between substorms to storms. However, the use of information theory methods which relies on time averages could hide the dynamics of the information flow. Indeed, the absence of a net information exchange between storms and substorms may be due to the fact that it is enhanced only during activity periods, so that it may be canceled out if transfer entropy is computed by averaging together quiet and activity periods.Here, we attempt an instantaneous estimation of the magnetospheric internal transfer of information during the occurrence of geomagnetic storms using an ensemble-based transfer entropy analysis. In detail using some geomagnetic indices as proxies of magnetospheric-ionosphere dynamics during geomagnetic storms, we investigate the directionality of the information flow within the magnetosphere-ionosphere system during the occurrence of periods of magnetic storms and substorms.

This work received funding by Italian MIUR-PRIN grant 2017APKP7T on Circumterrestrial Environment: Impact of Sun-Earth Interaction.
Molecular signatures of natural organic matter and anthropogenic contaminants from high altitude fresh water lake (Rewalsar) in NW Indian Himalaya 
Authors: Bulbul Mehta , Anoop Ambili
Published: March 2022

The n-alkane (n-C10 to n-C35) distributions and anthropogenic markers (sterol and PAH) from the surface sediments of Rewalsar Lake, Himachal Pradesh (India) were investigated to disentangle natural and anthropogenic organic matter sources. The presence of odd numbered n-alkanes (n-C27, n-C29 and n-C31) along with TAR, CPI and ACL values provide dominance of allochthonous over autochthonous organic matter sources. Detailed examination of allochthonous sources further reflect the accumulation of pollutants (PAHs and sterols) that mark the intensified toxicity and high degradation rates of lake system. The results obtained from diagnostic PAH indices highlight that the lake is immensely influenced by miscellaneous sources i.e, pyrogenic and petrogenic. Further, the occurrence of sewage contaminants particularly coprostanol and epicoprostanol suggest high anthropogenic loading due to sewage discharges. The overall accumulation of contaminants in the lake can be attributed to anthropogenic activities involving chemical and sewage overflow, agricultural and industrial discharges, land use changes, developmental activities. The uncontrollable pollution status of the Rewalsar lake is supported by low pristane/phytane (Pr/Ph) ratio that denotes anoxia. Moreover, dominance of coarse particles (silt and sand) over clay-sized particles further confirms high human intervention in the catchment area. Therefore, the study provides comprehensive understanding on organic matter source apportionment as well as role of anthropogenic stressors in the wake of rapid urbanization around Rewalsar lake.
Mapping Exposure to Landslides by Means of Artificial Intelligence and UAV Aerial Imagery in the Curvature Subcarpathians, Romania
Authors: Chitu Zenaida , Sandric Ionut , Ilinca Viorel , Irimia Radu
Published: March 2022

Curvature Subcarpathians is one of Romania's most complex geological and geomorphic areas, frequently affected by landslides. The juxtaposition of snowmelt and spring rainfalls triggers significant damages to roads and buildings every few years (2018, 2021). In this context, accurately delineating the most affected areas becomes critical for evaluating landslides exposure. Aerial images have begun to be used more and more for different risk assessment phases to detect natural phenomena spread and damaged infrastructure elements. In this study, we use fully automatic detection of the landslide body and infrastructure elements (intact or collapsed buildings and roads) to support Regional Civil Protection Agencies in disaster intervention decision support. Our methodology is based on deep learning techniques for automatic detection, mapping and classification of landslide and infrastructure elements. A U-Net model was trained to detect the landslide body, and several Mask RCNN models were trained to detect the landslide features and infrastructure elements. The training accuracy for the U-Net model used for landslide body mapping is 0.86, and the validation accuracy is 0.80. The training accuracy of the Mask RCNN models is 0.76 for landslide cracks, 0.82 for roads and 0.92 for buildings. Some confusions between landslide cracks and local roads without asphalt are often seen in rural areas. The models are run on high-resolution aerial imagery collected with Unammend Aerial Vehicles after a landslide event. The data obtained from the deep learning models are further integrated with information from various sources such as aerial/satellite imagery, online GIS resources, weather forecasts, and spatial analysis techniques for providing a helpful tool to emergency management specialists. The tools have been integrated into a GIS platform that acts as a decision support system, and it can be used from a graphical user interface without the need to have programming skills.

Acknowledgement

This work was supported by a grant of the Romanian Ministry of Education and Research, CCCDI - UEFISCDI, project number PN-III-P2-2.1-PED-2019-5152, within PNCDI III (project coordinator Ionuț Șandric, https://slidemap.gmrsg.ro) and by the project PN19450103 / Core Program (project coordinator Viorel Ilinca).
Quartz grain shape using S.E.M. in source-to-sink studies (production and transfer): the case example of the Cenozoic of the Paris Basin
Authors: Marie Nicolas , Guillocheau François , Briais Justine , Robin Cécile , Lasseur Eric
Published: March 2022

Understanding the source-to-sink system in sedimentary basins supposes the characterization of two key parameters: the source and the mode of sediment production (physical vs. chemical erosion), as well as the distance of the transfer zone. The shape of the quartz grains may record (1) the chemical vs. physical production of the grain, (2) the processes (eolian vs. fluvial) of sediment transfers, and (3) possible post-deposition emersion and weathering.

The criteria to distinguish chemical erosion are microstructures linked to dissolution (oriented etch pits, solution pits, solution crevasses and scaling) or precipitation (crystalline overgrowths and silica globules, flowers and pellicle). The difference between eolian and fluvial processes is mainly based on the roundness and the type of impact (conchoidal breakage, percussion marks and grooves).

This approach was successfully applied to the Cenozoic of the Paris Basin, a low accommodation sedimentary system (maximum 200 m in 35 Ma) encompassing numerous hiatuses. The source was mainly subjected to chemical erosion, since etching microstructures are often observed overcut by eolian or fluvial transport criteria. This chemical weathering is thought to has been particularly pronounced during Paleocene and early Eocene times. Eolian transport occurred preferentially during Danian, Lutetian and Bartonian times whereas fluvial transport appears dominant in Thanetian and Ypresian times. Major emersion marked by in situ chemical weathering occurred during Middle Paleogene times, Ypresian and Bartonian, with minor ones during Thanetian. This is testified by the superimposition of chemical weathering features on grains smoothed by fluvial and/or eolian transport.
Characteristics of a long-lived CIR and analytical modelling of the corresponding depression in the GCR flux
Authors: Dumbovic Mateja , Vrsnak Bojan , Heber Bernd , Temmer Manuela , Kuhl Patrick , Kirin Anamarija
Published: March 2022

We observe a long-lived CIR recurring in 27 consecutive Carrington rotations 2057-2083 in the time period from June 2007 - May 2009. We characterize the in situ measurements of this long-lived CIR as well as the corresponding depression in the GCR count observed by SOHO/EPHIN, and analyze them throughout different rotations. We find that the inverted GCR count time-profile correlates well with that of the flow speed throughout different rotations. We perform a statistical analysis and find the GCR count amplitude correlated to the peak in the magnetic field and flow speed, as expected based on previous statistical studies. In order to characterize a generic CIR profile for modelling purposes, we perform the superposed epoch analysis using relative values of the key parameters. Based on the observed properties we propose a simple analytical model starting from the basic Fokker-Planck equation. We employ a convection-diffusion GCR propagation model and apply it to the solar wind and interplanetary magnetic field properties observed for the analyzed long-lived CIR. Our analysis demonstrates a very good match of the model results and observations.
Comparison of CMIP6 and CMIP5 Models in Projections of Precipitation and Temperature over Central India
Authors: Saini Rohtash , Attada Raju , Pathaikara Akash
Published: March 2022

The South Asian monsoon is a lifeline of over two billion inhabitants of the Indian subcontinent. Hence, a reliable monsoon prediction system is essential for the operation of weather and climate over the region. The state-of-art General Circulation Models (GCMs) are powerful tools for monsoon prediction and assessing the effects of climate change on precipitation and temperature in rising extreme events such as floods, storms, heatwaves, and drought. However, selecting appropriate GCMs is a grand challenge for assessing climate change projections due to their significant uncertainties. The present study will evaluate the relative performance of GCMs of phases 5 and 6 of the Coupled Model Intercomparison Project dataset based on their multi-model mean (MMM) ability to project rainfall and temperature during the summer season (JJAS) over central India. In addition to the spatial patterns under the Shared Socioeconomic Pathways (SSPs), the study will also examine the model's ability to simulate interannual variability. The present research aims to determine the most reliable CMIP6 and CMIP5 datasets model and their comparison in simulation and projection of seasonal temperature and precipitation. The seasonal climatological mean of GCMs simulated rainfall and temperature shows variability at different scales over central India. CMIP6 multi-model mean demonstrate a reasonably well performance than CMIP5 in the seasonal mean cycle simulation with a better representation of the rainfall. The present study will also investigate the changes in sources of projection uncertainty and future precipitation indices. Finally, the current research will discuss the highlights of comparing the CMIP6 and CMIP5 datasets and their representations of better simulation performances based on the skill score metrics of precipitation and temperature indices.

KEYWORDS. CMIP6, CMIP5, MMM precipitation and temperature, Projection
Storylines of past and plausible future climates for recent extreme weather events with coupled climate models
Authors: Sánchez Benítez Antonio , Jung Thomas , Athanase Marylou , Pithan Felix , Goessling Helge
Published: March 2022

Under the ongoing climate change, extreme weather events are becoming more prolonged, intense, and frequent; and this trend is expected to continue in a future warmer climate. Several studies have found that the synoptic atmospheric circulation at the time of the event is the main contributing factor in most cases. Moreover, they are shaped by slower processes, including sea-surface temperature and soil moisture, in turn influenced by the history of preceding weather patterns, and by the background climate. The separation of influencing components is exploited by the storyline approach, where an atmosphere model is nudged toward the observed dynamics using different climate boundary conditions. Thus, the storyline approach focuses on the less uncertain thermodynamic influence of climate on extreme events, disregarding the somewhat controversial dynamical changes. This approach provides a very efficient way of making the impacts of climate change more tangible to experts and non-experts alike as events fresh in the people's memory are reproduced in different plausible climates with just moderate computational resources.

Spectral nudging experiments have been run with two coupled climate models, AWI-CM-1 and AWI-CM-3. In these simulations, the large-scale free-troposphere dynamics are constrained toward ERA5 data and the model is run for different boundary conditions. Here, the ocean and sea-ice state are consistently simulated, unlike previous studies which employed atmosphere-only models. Our setups reasonably reproduce daily to seasonal observed anomalies of relevant unconstrained parameters, including near-surface temperature, soil moisture or cloud cover. In particular, our configurations showed satisfactory skills in reproducing two different extreme events: the July 2019 European heat wave, and the July 2021 European extreme rainfall. Therefore, this methodology has been applied to study several extreme events in different climates. To do so, nudged simulations are branched off CMIP6 historical and scenario simulations of the same model. For the particular July 2021 extreme rainfall event, we have run five ensemble members for AWI-CM-1-1-MR for dynamical conditions from 1st January 2017 to 31st July 2021 in pre-industrial, present-day, +2K, and +4K climates. These simulations are complemented with similar experiments for AWI-CM-3. 

The most outstanding finding of these studies is a global warming amplification associated with some events, which exacerbates their exceptionality, especially in a high emission scenario.
Past changes in Atlantic Ocean circulation at intermediate water depths from micropaleontological and geochemical proxies since the last glacial maximum
Authors: Pourtout Solène , Sépulcre Sophie , Licari Laetitia , Colin Christophe , Michel Elisabeth , Siani Giuseppe
Published: March 2022

Ocean circulation plays a central role on climate regulation. The paleoceanographic studies of the last decades have allowed to better document the variations in the production of the North Atlantic Deep Water (NADW). However, the role of intermediate water (IW) masses through time remains to be documented and is highly controversial. Indeed, some studies have highlighted the increased contribution of the Antarctic Intermediate Water (AAIW) in all ocean basins during the cold events recorded in the North Atlantic [1] while others suggest their absence [2]. Moreover, during the last deglaciation, the Southern Ocean played a fundamental role in the Carbon transfer from the deep ocean to the atmosphere via the increased upwelling associated to the AAIW production. In order to reconstruct the dynamics of IW masses, to better understand the relationships between variations in ocean circulation in the Atlantic and in the Southern Ocean, and the impact of these changes on the global carbon cycle during Termination I, we use two marine sediment cores from the Porcupine basin MD01-2461 (1153m) and the Iberian margin SU92-28 (997m). We combine the study of benthic foraminifera assemblages sensitive to variations in their environment (nutrient content, oxygen), and different geochemical proxies such as elemental ratios (Mg/Ca, Sr/Ca, Cd/Ca, Ba/Ca, B/Ca, Li/Ca and U/Ca), stable isotopes (δ18O and δ13C) and Neodymium isotopes records (eNd). On core SU92-28, past changes in the benthic foraminiferal content exhibit strong differences in the paleo-environments, with different ecological conditions from the LGM to the Holocene, as well as during the YD and H1 events. These differences are also observed in the δ13C, oxygen concentrations and elemental ratios records obtained from Uvigerina peregrina (or U.mediterranea), Cibicidoides mundulus and Melonis affinis. Changes in the Nd record allow to distinguish changes in the IW mass sources, reflecting the balance between Northern and Southern contributions. Future analysis (e.g., 14C reservoir ages) and the comparison with core MD01-2461 records will help to better constrain the North-South connections in the Atlantic Ocean at IW depths, and their impact on global climate changes.

[1] Ma et al. (2019) Geochemistry, Geophysics, Geosystems, 20(3), 1592-1608

[2] Gu, S., et al. (2017). Paleoceanography, 32, 1036-1053.
Improving the assimilation part of the near real time system of IBI
Authors: Escudier Romain , Reffray Guillaume , Hamon Mathieu , Levier Bruno , Gutknecht Elodie
Published: March 2022

Ocean forecast for the IBI (Iberian-Biscay-Ireland) region are provided in near real time within the framework of the Copernicus Marine Environment Monitoring Service (CMEMS). They are produced with a physical–biogeochemical coupled model over the north-east Atlantic Ocean from the Canary Islands to Iceland, including the North Sea and the western Mediterranean. 

The physical system, composed of a NEMO model at 1/36° resolution (around 2km, ORCA grid subset), has started operating in the early 2010s and continuously evolved with regular releases. Its ocean model is corrected through the assimilation of in-situ observations (T and S profiles) and satellite data (Sea Surface temperature, SST and altimetry) with the Assimilation System of Mercator (SAM) which is based on the SEEK Kalman filter. 

A CMEMS release is planned for 29th of November this year and a new version of the system will be operational. We will describe here the last evolution of the system focusing on the data assimilation updates. Changes in the model equivalent for the satellite Sea Level Anomaly (SLA) using a new formulation for the barotropic part leads to a better estimation of the innovation. The impact of this change and a discussion on the Mean Dynamic Topography (MDT) used will be developed. 
Modelling mean radiant temperature in complex urban areas using a convolutional network approach
Authors: Briegel Ferdinand , Makansi Osama , Brox Thomas , Matzarakis Andreas , Christen Andreas
Published: March 2022

We present a novel method to model spatial maps of mean radiant temperature (Tmrt) in complex urban areas using a special type of fully convolutional networks - U-Net - for image to image processing. Tmrt is one of the driving factors of daytime human thermal comfort and underlies great spatial and temporal variabilities, especially in complex urban areas. Various micro scale (building-resolving) models exist to model Tmrt in urban settings. However, these models are computational expensive, albeit to varying degrees. This means, study area and time might be limited depending on spatial and temporal resolution. While this is sufficient for case studies where micro-level processes are modelled for different neighbourhoods in limited time periods, accurate calculations over a long time period are not possible (e.g. downscaling global climate projections). To overcome these computational drawbacks of physical models, we present a U-net approach for modelling Tmrt in complex urban areas.

U-Nets are special types of encoder-decoder networks and allow precise image to image processing. In this study, Tmrt (at 1.1 m a.g.l.) is modelled by SOLWEIG model for 62 areas (500 x 500 m2) and on 54 days for the city of Freiburg, Germany. Training data is sampled randomly after clustering. The spatial and temporal input of SOLWEIG are in turn used as input features for the U-Net. The U-Net is trained on 56 areas and on 45 days and tested on the remaining areas and days. In addition, data from a Tmrt measurement campaign is used to validate SOLWEIG and U-Net model output.

Results indicate that the proposed U-Net approach is capable to provide Tmrt in complex urban areas sufficiently. A correlation of > 0.9 and a MAE of 1.53°C between SOLWEIG and the U-Net is observed. Results show a higher MAE during day than night, which can be partly explained by the difference of absolute Tmrt values at day and night, but also by more complex prediction conditions during day: cloud cover and thus varying radiation, but also low sun angle in the morning / evening. In addition, computing times for Tmrt map predictions are significantly faster than physical models. 
Millennial-scale interactions of the Antarctic Ice Sheet and the global ocean
Authors: Kreuzer Moritz , Huiskamp Willem , Albrecht Torsten , Petri Stefan , Reese Ronja , Feulner Georg , Winkelmann Ricarda
Published: March 2022

Increased sub-shelf melting and ice discharge from the Antarctic Ice sheet has both regional and global impacts on the ocean and the overall climate system. Additional meltwater, for example, can reduce the formation of Antarctic Bottom Water, potentially affecting the global thermohaline circulation. Similarly, increased input of fresh and cold water around the Antarctic margin can lead to a stronger stratification of coastal waters, and a potential increase in sea-ice formation, trapping warmer water masses below the surface, which in turn can lead to increased basal melting of the ice shelves.

So far these processes have mainly been analysed in simple unidirectional cause-and-effect experiments, possibly neglecting important interactions and feedbacks. To study the long-term and global effects of these interactions, we have developed a bidirectional offline coupled ice-ocean model framework. It consists of the global ocean and sea-ice model MOM5/SIS and an Antarctic instance of the Parallel Ice Sheet Model PISM, with the ice-shelf cavity module PICO representing the ice-ocean boundary layer physics. With this setup we are analysing the aforementioned interactions and feedbacks between the Antarctic Ice Sheet and the global ocean system on multi-millenial time scales.
Optimal real-time control of water distribution systems undergoing cyber-physical attacks
Authors: Murillo Andres , Salaorni Davide , Taormina Riccardo , Galelli Stefano
Published: March 2022

In recent years, researchers have developed intrusion detection tools to improve the security of Water Systems in the presence of novel and sophisticated cyber-attacks. Nevertheless, such tools lack prescriptive analytics conceived to determine the best course—that is, how to control a system undergoing an attack. Here, we fill in this gap by presenting a numerical modelling framework based on the coupling of DHALSIM with a Deep Q-Learning agent.  The former is a simulation environment providing a high-fidelity representation of both hydraulic processes and ICT devices, while the latter is an optimal control algorithm tasked with the problem of curbing the impact of cyber-physical attacks by re-operating key hydraulic devices, such as pumps and valves. Their integration is made feasible thanks to a new feature implemented in DHALSIM—the stepwise simulation—allowed by the addition of a new simulator wrapper, namely Epynet. The evaluation phase is run considering the system in normal operating conditions and undergoing cyber-attacks. Our results show a good behaviour in terms of Demand Satisfaction Ratio. In particular, the control agent manages to satisfy the customers demand, without overflowing the tanks in the system.  To our knowledge, these results are the first in the unexplored area of attack recovery in water distribution systems.