bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental analysis of seasonal processes in shallow landslide in a snowy region through downscaled and in situ observation
Authors: Longoni Laura , Panzeri Lorenzo , Mondani Michele , Papini Monica
Published: March 2022

The frequency and intensity of heavy precipitation events increased since the mid-20th century and, considering the climate crisis, it is important also to analyze the effects of processes and events that lead to faster snow mantle melting cycles in mountain areas.

Shallow landslides are induced by extreme hydrological events such as the occurrence of short and intense rainfall or by events of medium intensity but prolonged over time. Such slips involve generally reduced portions of land both in area and in thickness, however, they are dangerous due to the absence of warning signals and the lack of knowledge regarding their possible evolution.

This work deals with the experimental study of these landslides through the laboratory simulations on a small-scale slope, reproduced at the LIMAG Lab - Laboratory of mountain hydraulics and applied geology of the Lecco Campus and in situ seasonal processes observation at a mountain closed basin nearby Champoluc village in Aosta Valley region.

The central objective is to study the evolution of shallow landslides in reduced scale caused by external factor as snowmelt and rainfall and to compare the observations done in laboratory with the ones in situ. In order to investigate the behaviour of shallow landslides in these critical conditions, a series of sensors have been installed on the simulator. This technology includes three modified pressure transmitters for the pore water pressure evaluation which have been accompanied by other support instrumentation consisting of GoPro’s cameras, TDR (Time Domain Reflectometry) and georesistivimeter; all of them provide a cross check of phenomena processes.

Throughout the downscaled simulations with snow cover it was possible to observe several processes. The direct interaction between snow and ground does not favor the infiltration of a large amount of water. The protective role of snow lies in keeping the first film of soil at 0 degrees and loading the soil by decreasing its infiltrative capacity; this no longer occurs when the water melted by the snow flows downstream and begins to infiltrate into uncovered and warmer soils. Without thermal or overload barriers, the water pours into the ground. Therefore, a potential susceptible area can be the subject of different filtering and infiltrative contributions from upstream, saturating quickly and collapsing.

These laboratory experiments are the starting point for the in-situ analyses and provide a comparison with the observations made by means of ad hoc instrumentation set up at the Champoluc station. Highly detailed information is obtained concerning the density and thickness of the snowpack during seasonal processes. These contribute to defining the hydrogeological processes within the terrain, already studied in the laboratory, and to establishing the water balance.
Zonal wavenumber spectra of the vertical velocity and horizontal wind divergence associated with the Rossby and non-Rossby waves in the tropics
Authors: Neduhal Valentino , Žagar Nedjeljka , Zaplotnik Žiga
Published: March 2022

In contrast to the kinetic energy spectrum of the horizontal motions, the spectrum of kinetic energy of vertical motions (vertical kinetic energy spectrum) is poorly known because the vertical velocity is not an observed quantity of the global observing system. The vertical kinetic energy spectra can be simulated by non-hydrostatic models but are difficult to validate. Furthermore, contributions to the vertical kinetic energy spectrum from the Rossby and gravity waves have traditionally been treated separately using the quasi-geostrophic omega equations and the polarization relations for the stratified Boussinesq fluid, respectively. This approach is difficult to apply in the tropics, where the Rossby and gravity wave regimes are nonseparable and the frequency gap between the Rossby and gravity waves, present in the extra-tropics, is filled with the Kelvin and mixed Rossby-gravity waves.  

We apply a unified framework for the derivation of vertical velocities of the Rossby and inertia-gravity waves and associated kinetic energy spectra using the eigensolutions of the linearized primitive equations. It can be considered applicable to the hydrostatic atmosphere with horizontal scales up to around 10 km.  The derivation involves the analytical evaluation of divergence of the horizontal wind associated with the Rossby and inertia-gravity modes. The new framework is applied to the ECMWF analysis in August 2016 and August 2018. Latitude and altitude dependence of the horizontal wind divergence and vertical kinetic energy spectra within the tropics are discussed and compared with observations over the tropical Atlantic. In particular, we discuss the slope of the vertical kinetic energy spectra for the two dynamical regimes.
Evidence of ecological critical slowing-down in temperate soils
Authors: fraser fiona , Corstanje Ronald , Todman Lindsay , Bello-Curás Diana , Bending Gary , Deeks Lynda , Harris Jim , Hilton Sally , Pawlett Mark , Zawadzka Joanna , Whitmore Andrew , Ritz Karl
Published: March 2022

The resilience of ecological systems is crucially important, particularly in the context of climate change. We present experimental evidence of critical slowing-down arising from perturbation of a key function in a complex ecosystem, exemplified by soil. Different behavioural classes in soil respiratory patterns were detected in response to repeated drying:rewetting cycles. We characterised these as adaptive, resilient, fragile or non-resilient. The latter involved increasing erratic behaviour (i.e. increasing variance), and the propagation of such behaviour (i.e. autocorrelation), interpreted as a critical slowing-down of the observed function. Soil microbial phenotype and land-use were predominantly related to variance and autocorrelation respectively. No relationship was found between biodiversity and resilience, but the ability of a community to be compositionally flexible rather than biodiversity per se appeared to be key to retaining system function. These data were used to map the extent to which soils are close to crossing into alternative stable states at a national scale.
Status and prospects for the neXtSIM-F CMEMS operational forecast
Authors: Williams Timothy , Korosov Anton , Olason Einar , Bertino Laurent
Published: March 2022

The neXtSIM-F operational forecast was upgraded in December 2021, with the following developments:

improvements to the rheology, with the neXtSIM model now running the latest version of the Brittle Bingham-Maxwell rheology (BBM).
  The previous version  was running a preliminary version of the BBM rheology.

The model domain was extended to include the Labrador Sea, Hudson and Baffin Bay.

Better tuning of dynamic (eg of basal stress parameters for the fast ice off the coast of the eastern Arctic)  and thermodynamic parameters.

The upgrade resulted in good improvements to the ice thickness and extent, although drift developed a slight slow bias. However the bias is of the order
of the observation error (1-1.25km/day).

Planned developments for the next 3 years include:

assimilation of ice thickness data

assimilation of ice extent from NIC ice charts (National Ice Center, USA)  instead of from passive microwave (OSISAF).

increased resolution, to go from about 7.5km to about 3.75km

a multi-year reanalysis to be updated every month
Seismic Response of A Large Deep-seated Rock Slope Revealed by Seismic Monitoring and Geological Surveys
Authors: Cui Shenghua , Pei Xiangjun , Wang Hui
Published: March 2022

In order to better understand the influence factors of the seismic response of the deep-seated unstable rock slope, we installed four high-sensitivity three-component integrated seismometers on Shidaguan slope (SDG slope) in Mao County, Sichuan Province, China. One of the seismometers was located at the stable part of SDG slope and at the highest elevation, while the other three were located in the deformation area of SDG slope. Nearly 100 sets of shallow source seismic data were acquired over a three-year period of seismic monitoring. Meanwhile, we carried out a detailed geological surveys by electrical resistivity tomography and drilling. Taking the monitoring point located at the stable part as a reference point, the peak acceleration obtained by the three seismometers located in the deformed area was compared to it. By this way, it is revealed that the seismic response of the reference point was the weakest, although it was at the highest elevation. The same phenomenon was obtained using the spectral ratio horizontal-to-vertical component of the seismic records (referred to here as HVSR). This is because that the fractured rock mass can act as a resonator, causing standing waves to develop in the broken rock mass. And the surface, as a free face, could show the strong ground shaking response. At the same time, we found that the seismic response was different for the three monitoring points in the deformed area of SDG slope. The seismic response of the deformed body with large thickness is smaller than that of the deformed body with small thickness. In order to analyse the reasons for the different amplification, we discussed the relationship between the amplification and the physical properties of rock mass. Rock mass with low resistivity and RQD caused seismic response amplification. However, this amplification was suppressed by that rock mass which exhibits viscoelasticity. The amplification of the ground shaking response would be influenced by the lithofacies difference degree in unstable areas, which should be taken into account when constructing buildings in landslide-prone mountainous areas.
Eddy-Internal wave decomposition and kinetic energy transfers in high-resolution turbulent channel flow with near-inertial waves
Authors: shaham michal , Barkan Roy
Published: March 2022

Oceanic mesoscale eddies contain most of the kinetic energy (KE) in the ocean and therefore play an important role in determining the ocean’s response to future climate scenarios. Oceanic wind-forced internal waves (IWs) are energetic fast motions that contribute substantially to the vertical mixing of water, thereby affecting biogeochemical and climate processes. We study the effects of wind-forced IWs on the KE pathways in high-resolution numerical simulations of an idealized wind-driven channel flow. Using spectral fluxes, we demonstrate that solutions with wind-forced IWs are characterized by a forward KE cascade, whereas solutions without exhibit an inverse KE cascade. We further decompose the flow field into ‘eddy’ and ‘internal wave’ motions using a Helmholtz decomposition and temporal filtering. This allows us to identify three key processes responsible for the reversal in the KE cascade: IW scattering, direct extraction, and stimulated cascade. Each process is quantified and discussed in detail.
Historical earthquake simulation using ambient seismic noise in Vrancea (Romania): preliminary results
Authors: Placinta Anica Otilia , Petrescu Laura , Borleanu Felix , Radulian Mircea
Published: March 2022

The Vrancea Seismic Zone (VSZ), located in Romania, at the sharp bend of the southeastern Carpathians, is an anomalous intraplate seismic region releasing the largest strain in continental Europe. The seismicity is concentrated in a high-velocity focal volume down to 200 km, challenging classic earthquake mechanism theories due to its remote location and deep hypocenters in an expectedly ductile lithosphere. The last significant earthquake in Vrancea occurred in 1977 causing destruction to Romanian cities and long-term economic damage to an already struggling developing country. The seismic infrastructure was underdeveloped in Romania at that time and the earthquake was not well-recorded locally. The recent increase in seismic station coverage in Romania now provides the opportunity to systematically study seismogenic processes and apply the most novel processing methods.

We apply the recently developed algorithm of Virtual Earthquake Approach (VEA, Denolle et al., 2013) to reconstruct realistic ground motion records as if the stations operating today recorded historical earthquakes, such as the 1977 event. Predicting accurate ground motion is critical for earthquake hazard analysis, particularly in situations where sedimentary basins trap and amplify seismic waves. We gathered one year of three-component ambient noise data from 44 broadband seismic stations around the VSZ. We then construct the ambient noise Green’s tensor between pairs of stations and add the signatures of a realistic earthquake: double couple mechanism, buried source and a realistic earth model in the epicentral area.

Using the Romanian earthquake catalog (Romplus, www.infp.ro), we selected the last Mw>6.0 earthquakes since 1940 from the area and extracted the moment tensor solutions. Subsequently, we simulate the ground motion generated by these earthquakes recorded by modern seismometers decades after their occurrence. Our new results demonstrate the viability of this innovative method and provide a unique opportunity for more accurate seismic hazard analysis.

Keywords: ambient noise, historical earthquake, virtual earthquake approach.

Reference:

A. Denolle, E. M. Dunham, G. A. Prieto, G. C. Beroza, Ground motion prediction of realistic earthquake sources using the ambient seismic field, Journal of Geophysical Research: Solid Earth, Vol. 118, 2102–2118, doi:10.1029/2012JB009603, 2013.

 
Statistical characteristics of ionospheric irregularities in the cusp ionosphere based on multi-instrument techniques
Authors: Spicher Andres , Vierinen Juha , Oksavik Kjellmar , Jin Yaqi
Published: March 2022

Plasma density irregularities disturbing signals from Global Navigation Satellite Systems (GNSS) are known to be regular features of the high-latitude ionosphere, especially around the cusp and auroral regions. Despite their relevance for society, irregularity formation and evolution are still relatively poorly understood, and observations revealing the spatio-temporal characteristics of ionospheric structuring at different scales are needed to assess the exact mechanism(s) responsible for them.

In this study, we focus on data from the European Incoherent Scatter Scientific Association (EISCAT) Svalbard Radars (ESR) operating in fast scanning mode. We use ESR experiments in which the antenna was swept in elevation, and create consecutive two-dimensional images showing how electron density, ion velocity, electron temperature, and ion temperatures change with latitude and time at different altitudes.

We present selected events in which the ESR scans are combined with all-sky images and in-situ data from the Swarm satellites to provide multi-scale observations of cusp phenomena comprising polar cap patches, flow channels, particle precipitation, and ion heating.  We compare the observations with the presence of GNSS scintillations, allowing to monitor the onset and development of irregularities causing scintillations, and to inspect their connection with the phenomena above-mentioned. We then extend the analysis by performing a statistical study using all ESR fast scans identified between January 2001 and December 2015. We investigate the statistical characteristics of the measured parameters at different altitudes and under different geomagnetic conditions. Overall, this study will provide further insights onto the spatio-temporal evolution of ionospheric cusp dynamics, and on the possible physical sources causing ionospheric irregularities with Space weather impacts.
Summertime evaporation over glacial lakes in the Schirmacher oasis, East Antarctica.
Authors: Shevnina Elena
Published: March 2022

The summertime evaporation over a large shallow lake located in the Schirmacher oasis, Dronning Maud Land, Antarctica. Lake Zub/Priyadarshini is the second largest lake in the oasis,  its maximum depth is  6 m. The lake is among the warmest lakes, and it is free of ice during almost two summer months. The summertime evaporation over the water table of the lake was estimated after the eddy covariance (EC) method, the bulk aerodynamic method and Dalton type empirical equations. We used special meteorological and hydrological measurements collected during the field experiment carried out in 2018 in addition to the standard observations at the nearest meteorological site. 

The EC method was considered as the most accurate given a reference for other estimates of evaporation over the lake water surface. We estimated the evaporation over the ice free lake surface as 114 mm in the period from 1 January to 7 February 2018 (38 days) after the direct EC method. The average daily evaporation is estimated to be 3.0 mm day-1 in January 2018. The largest changes in the daily evaporation were driven by the synoptic-scale atmospheric processes rather than local katabatic winds. 

The bulk aerodynamic method suggests the average daily evaporation to be 2.0 mm day-1 , and it is over 30 % less than the EC method. This method is much better in producing the day-to-day variations in evaporation compared to the Dalton type semi-empirical equations, which underestimated the evaporation over the lake open water table for over 40–72 %. We also suggested a linear empirical relationship to evaluate the summertime evaporation of Lake Zub/Priyadarshini from the observations at the nearest meteorological site and surface water temperature. After this method, the evaporation over the period of the experiment is 120 mm, and it is only 5 % larger than the result according to the EC method. We also estimated the daily evaporation from the ERA5 reanalysis, which suggested the average daily evaporation during austral summer (December – February) 2017–2018 to be 0.6 mm day-1. It is only one fifth of the evaporation estimated with the direct EC method. 

The poster shows the results which were obtained together with Timo Vihma and Tuomas Naakka (Finnish Meteorological Institute, Helsinki, Finland), Miguel Potes (Institute Earth Science, Evora, Portugal), Pankaj Ramji Dhote and Praveen Kumar Thakur (Indian Institute of Remote Sensing, Dehradun, India). The study was funded by the Academy of Finland (contract number 304345) and the COST Snow Action ES1404. The measurement campaigns were supported by the Finnish Antarctic Research Program, the Russian Antarctic Expedition, and the Indian Antarctic expedition.
A Method for Estimating the Evolution of Brewer-Dobson Circulation Upwelling
Authors: Charlesworth Edward , Diallo Mohamadou , Plöger Felix , Birner Thomas , Jöckel Patrick
Published: March 2022

Both theory and climate model results suggest that the Brewer-Dobson circulation should strengthen with increasing greenhouse gas concentrations. Can this be confirmed by observations?

Directly measuring the circulation strength is not possible, so verification of this sensitivity has been limited to inferences from observations of long-lived chemicals. These methods, however, are complex and accumulation of the data required for them is difficult. Meanwhile, ozone observations are available from multiple sources spanning decades, but have only been applied to qualitative study of the stratospheric circulation, until now.

In this work, we present a new quantity - effective upwelling - which can be derived from ozone observations by a simple calculation. We then show that effective upwelling anomalies can be an effective proxy for residual circulation (i.e. TEM) upwelling. We present a comparison of TEM upwelling and effective upwelling calculated from CCMI model data to show the validity of the method, and follow this by presenting seasonal cycles, trends, and variability of effective upwelling as calculated by satellite observations.
Monitoring the Black Sea climate: recent advancements for building ocean indicators
Authors: Lima Leonardo , Ilicak Mehmet , Gunduz Murat , Causio Salvatore , Peneva Elisaveta , Angela Ciliberti Stefania , Aydoğdu Ali , Azevedo Diana , Stefanizzi Laura , Clementi Emanuela , Coppini Giovanni , Masina Simona , Pinardi Nadia
Published: March 2022

Ocean reanalyses reconstruct the ocean state with a long integration of an ocean model constrained by atmospheric surface forcing and observations via data assimilation. Since their results are more accurate in comparison to those derived from a model alone, they are a powerful tool to provide ocean monitoring indicators (OMIs) as well as to better understand the physical properties and dynamics of the Black Sea. In the scope of the Copernicus Marine Service (CMEMS), the Black Sea physical reanalysis (BS-REA) system has been used to support the implementation of new indicators in the Black Sea. The system is built upon the hydrodynamic model NEMO v3.6 at 1/27° x 1/36°, and 31 unevenly distributed vertical levels, coupled to OceanVar for the assimilation of the best available observations (both in situ and satellite ones). In this contribution, we present the current operational indicators for the monitoring of temperature and salinity anomalies. BS-REA system provides temperature trends that indicate a warming of the basin: 0.0829±0.01069 oC year-1, 0.0380±0.0005 oC year-1, 0.0041±0.0001 oC year-1, respectively, in 0-25 m, 25-150 m and 150-300 m. Since 2007, the warming signal has been very clear in such a way that the Black Sea cold intermediate layer (CIL) almost disappeared in recent years. However, this continuous warming is interrupted in 2012 and less explicitly in 2017, years in which a replenishment of the CIL is verified. Similar analyses for salinity reveal that salinity trends reduce in depth and are larger from 2005, especially in surface layers. The system is very suitable for understanding the physical state of the Black Sea in recent years and allows to obtain more accurate OMIs for the sea, which are important to understand its response to climate change. 

Following recent CMEMS Ocean State Report contributions, new OMIs based on the ocean heat content anomaly and freshwater content anomaly will be produced this year, whereas indexes on the basis of the interannual variations of the Black Sea Rim Current intensity, the Black Sea overturning circulation and the coastal upwelling along the Turkish coast will be provided as OMIs in the near future. BS-REA is under continuous update in order that new versions will bring improvements in both the numerical model and data assimilation components.
Variations of the Earth magnetic field: From geomagnetic storms to field reversal
Authors: Leonhardt Roman
Published: March 2022

The geomagnetic field, the Earth’s primary barrier against charged particles from the sun, varies on time scales from million years to sub-second fluctuations. In the past decades significant advances in measurement techniques, both ground and space based, paleo- and rock magnetic methods, as well as numerical and analytical simulations, improved our understanding of underlying processes and their consequences on our planet and on our society. Geomagnetic storms, often related to coronal mass ejections on the sun and their interaction with the Earth‘s magnetic field, pose a threat to our modern society as they affect satellites, disturb radio communication, and, in particular, damage power grids and cause electrical blackouts on a massive scale. Ground based measurements, which are used together with satellite data to investigate these events, point towards the occurrence of global scale major storms once every 100 years. When further looking at such observatory data, which is existing for the last few hundred years, it is also striking that the global Earth‘s magnetic field is gradually weakening, by more the 10% in the past 200 years. Paleo- and archeomagnetic investigations are used to extend our observational range into the past in order to clarify the significance and reasons of this field reduction. When looking even further into the past, complete flips of the geomagnetic field are recorded in geological archives like volcanic rocks and sediments. These geomagnetic field reversals, the last one happening about 770kyrs ago, are accompanied by strong reductions of the geomagnetic field strength and complex field behavior on the Earths surface, effects which are sometimes brought into connection with our modern observation of field reduction. This presentation will provide a comprehensive overview about geomagnetic field variations, and the necessity of using long timeseries for interpretation of its current state and future evolution.
Molecular biomarkers and carbon turnover data in ice-rich permafrost in Yakutia
Authors: Jongejans Loeka , Mangelsdorf Kai , Liebner Susanne , Grosse Guido , Grigoriev Mikhail , Fedorov Alexander , Strauss Jens
Published: March 2022

With ongoing climate warming, ice-rich permafrost, such as late Pleistocene Yedoma permafrost, is especially vulnerable to rapid and deep thaw processes. Such permafrost sediments contain a large organic matter storage that becomes increasingly accessible to microbes upon thaw. Only a few studies analysed organic matter in deep (>10 m) permafrost and thawed permafrost sediments. We studied Yedoma sediments from four sites in Yakutia in the Russian Federation: at the Arctic Ocean (Bykovsky Peninsula), inside the Lena Delta (Sobo-Sise Cliff), close to the northern hemisphere’s cold pole (Batagay) and in central Yakutia (Yukechi Alas). We measured biomarker concentrations of sediment cores taken from below thermokarst lakes and sediment samples taken from the headwall of a coastal bluff and a retrogressive thaw slump. In addition, we carried out incubation experiments to quantify greenhouse gas production in thawing permafrost. Here, we present the first molecular biomarker distributions (alkanes and fatty acids) and organic carbon turnover (anaerobic CO2 and CH4 production) data as well as insights in organic matter decomposition processes in deep frozen and thawed Yedoma sediments. We show that biomarker proxies are useful to assess the source and degree of degradation of permafrost organic matter. Furthermore, the organic matter in frozen Pleistocene Yedoma sediments was better preserved than in thawed Holocene sediments. These findings show the relevance of studying organic matter in deep permafrost sediments.
New EUFAR flight finder
Authors: Retornard Vianney , Boulanger Damien , Garland Wendy , Formenti Paola
Published: March 2022

EUFAR (EUropean Facility for Airborne Research, https://www.eufar.net) was born out of the necessity to create a central network for the airborne research community in Europe with the principal aim of supporting scientists, by granting them access to research aircraft and instruments otherwise not accessible in their home countries. With time EUFAR has grown, introducing new activities and objectives to place itself as the unique network and portal of airborne research for the environmental and geosciences in Europe. From serving as an interactive and dynamic hub of information, to maintaining a central data archive, and developing tools and standards to collect, process and analyse data, EUFAR continues to improve the operational environment for conducting airborne research.

 EUFAR's data archive activity seeks to improve access to and use of the data collected by instrumented aircraft in Europe, providing a unique portal to the data along with supporting metadata. AERIS, the French Data and Services Cluster for Atmosphere (https://en.aeris-data.fr) has implemented a new Data and Metadata Catalogue for EUFAR that in the longer term is intended to become a principal data portal for the European airborne science community.

All EUFAR datasets are following the FAIR principles. The main features of the catalogue, i.e. data and metadata discovery and download, have been improved. Advanced services have been implemented such as the discovery of external datasets from EUFAR partners starting with the French Research Airborne Data Portal SAFIRE+. This will be extended to other databases in 2022 such as DLR, NERC-ARF, FAAM, Met Office, etc. New advanced features are currently under development: discovery of datasets from other airborne Research Infrastructures (IAGOS, HEMERA, etc.); data visualization services; integration of the EUFAR products and services in EOSC (European Open Science Cloud); tools for the management of campaigns metadata, etc.

 
Weakening mechanisms in dry, lower-crustal pseudotachylytes
Authors: Dunkel Kristina G. , Menegon Luca , Jamtveit Bjørn
Published: March 2022

Earthquakes are often regarded as agents of rheological weakening of the dry and mechanically strong lower crust. The weakening is typically attributed to fluid infiltration and resulting fluid-mediated metamorphism along the seismic fault.

On Moskenesøya in SW Lofoten (Northern Norway), we observe lower-crustal pseudotachylytes (frozen frictional melts that record fossil earthquakes) that are unusually dry. This presents us with an exceptional opportunity to study the processes affecting the rocks during and after an earthquake:

We can observe the pristine microstructures of the pseudotachylytes, not overprinted by later metamorphism, to elucidate the earthquake-generating mechanism.

We can study the further development of these dry pseudotachylytes after the seismic event.

We have previously described the composition and microstructures of the pristine pseudotachylytes, and concluded that transient stress pulses caused by shallower earthquakes are the most likely explanation for the occurrence of fossil earthquakes in the analysed rocks from Lofoten, with no evidence of other mechanisms such as thermal runaway or dehydration embrittlement.

In this contribution, we focus on the evolution of the pseudotachylytes after their formation. We study their development from the initial, pristine pseudotachylytes, via pseudotachylytes with slightly mylonitized margins, to ultramylonites. We use compositional and microstructural analyses, including electron backscatter diffraction (EBSD), to understand the weakening mechanisms in this dry system.

In the mylonitized margins of the pseudotachylytes, a slight shape-preferred orientation is developed and the quenching microstructures, such as microlites, are lost. The mineralogical composition (dominantly feldspars and pyroxenes) stays the same as in the pristine pseudotachylytes. In the ultramylonite, quartz and amphibole appear as accessory minerals, which means that we cannot completely exclude the presence of minor amounts of hydrous fluids; however, feldspars and pyroxenes persist as the main components of the rock. The foliation of the ultramylonite is not defined by phyllosilicates, but by a compositional banding, which suggest a phase separation and aggregation during shearing. EBSD data indicate that the main constituent phases deformed dominantly by grain size sensitive creep.

Our preliminary results suggest that even in the absence of fluids, pseudotachylyte-bearing seismic faults represent weak zones in the lower crust that are localizing viscous shear during post- and interseismic deformation, presumably due to the intense grain size reduction that facilitates grain-size sensitive mechanisms. 
Airbone data strategy in the French National cluster AERIS
Authors: Bex-Chauvet Olivier , Payan Sébastien , Boulanger Damien , Bouhouili Asmae , Retornard Vianney , Boonne Cathy
Published: March 2022

AERIS, the French Data and Services Cluster for Atmosphere (https://en.aeris-data.fr), aims to facilitate and enhance the use of French atmospheric data acquired by satellites, ground-based facilities and airborne platforms during long observation periods and scientific campaigns. AERIS manages a large set of datasets acquired on aircraft or balloons platforms.

AERIS is the Data Centre for the European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System) that acquires readings of atmospheric composition from instrumented international commercial airliners. AERIS also manages all data obtained from airborne scientific survey campaigns flown over nearly 30 years, by French research aircraft today operated by the SAFIRE unit, accessible through the SAFIRE+ portal. AERIS recently developed the new version of the EUFAR (EUropean Facility for Airborne Research) data catalogue.

In AERIS, data from balloon survey campaigns operated by the international science community are managed and distributed in a unified fashion. Through the European HEMERA (Integrated access to balloon-borne platforms for innovative research and technology) project, AERIS provides archive balloon survey data and an environment to accommodate future campaigns.

All the data are openly accessible to the scientific community. Recently, AERIS has been working on the application of the FAIR principles with an emphasis on the implementation of interoperability. Cross discovery of all the datasets is implemented or under development on the different data portals with links between AERIS airborne datasets and external ones. Specific advanced services have been implemented, such as aircraft and balloons trajectories visualisation, data plotting, etc.

AERIS as well supports airborne campaigns providing services like operational websites offering various digital tools to facilitate the organisation of measurement campaigns (website, data repository, specific products, quicklooks, trajectory forecast, satellite colocation, etc.). Catalogues are also proposed for discovery and publication of the data acquired during the campaigns.
Deciphering Hydroclimatic Complexity with Information Physics and Quantum Technologies
Authors: Perdigão Rui A. P. , Hall Julia
Published: March 2022

Discerning the dynamics of complex systems in a mathematically rigorous and physically consistent manner is as fascinating as intimidating of a challenge, stirring deeply and intrinsically with the most fundamental Physics, while at the same time percolating through the deepest meanders of everyday life.

The socio-natural coevolution in hydroclimate dynamics is an example of that, exhibiting a striking articulation between governing principles and free will, in a stochastic-dynamic resonance that goes way beyond a reductionist dichotomy between deterministic and probabilistic approaches and between physical principles and information technologies.

Subjacent to the conceptual and operational interdisciplinarity of that challenge, lies the simple formal elegance of a “lingua franca” for communication with Nature. This emerges from the innermost mathematical core of Information Physics articulating the wealth of insights and flavours from frontier natural, social and technical sciences in a coherent, integrated manner.

Communicating thus with Nature, we equip ourselves by developing formal innovative methodologies and technologies to better appreciate and discern complexity in articulation with expert knowledge. Thereby opening new pathways to assess and predict elusive non-recurrent phenomena such as irreversible geophysical transformations and extreme hydro-meteorological events in a coevolutionary climate.

Our novel advances will be shared across the formal, structural and functional theory of the Information Physics of Coevolutionary Complex Systems, along with the analysis, modelling and decision support in crucial matters afflicting our environment and society, with special emphasis onto hydroclimatic problems.

In an optic of operational empowerment, some of our flagship initiatives will be addressed such as Earth System Dynamic Intelligence and Quantum Information Technologies in the Earth Sciences (QITES) on a synergy among our information physical and quantum technological developments.

The articulation between these flagships leverages our proprietary synergistic quantum gravitational and electrodynamic QITES constellation from deep undersea to outer space to take the pulse of our planet, ranging from high resolution 4D sensing and computation to unveiling early warning signs of critical transitions and extreme events.
Effect of different tillage methods on soil N2O emission in an arable field 
Authors: Dencső Márton , Saliga Rebeka , Molnár Sándor , Tóth Eszter
Published: March 2022

In this study we investigated the effect of mouldboard ploughing (MP), shallow cultivation (SC) and no-tillage (NT) methods on N2O emission of a Central European long-term field experiment. We measured N2O fluxes and environmental parameters (soil moisture and temperature) in three replicates per treatment on a biweekly to mounthly basis during two and a half year period. Besides regular measurements we carried out additional occasions timed to heavy rainfalls. N2O fluxes occured after fertilization and on soils under high soil moisture conditions only, during spring and autumn. The average N2O emission for the whole experimental period was the highest in NT (0.025±0.045 µg N2O m-2 s-1), which was significantly higher (p<0.005) than in MP (0.004±0.003 µg N2O m-2 s-1) or SC (0.003±0.003 µg N2O m-2 s-1). Soil mositure was a significant (p<0.005) environmental driver of N2O emissions in NT treatment.
Limnological responses to active management of the invasive aquatic fern Salvinia molesta in Las Curias Reservoir, San Juan, Puerto Rico.
Authors: García López Xavier , Ortiz Zayas Jorge , Díaz Rodrigo , Castro Jiménez Aurelio , Abdelrahman López Moisés
Published: March 2022

In the Anthropocene, human action and globalization are closely linked to the deterioration of natural habitats and water resources. Invasive aquatic weeds have been recognized as a major problem in watersheds worldwide due to their environmental impacts. This study focuses on the management of the Las Curias Reservoir in Cupey Puerto Rico in the Río Piedras watershed since the arrival of Salvinia molesta after Hurricane María in 2017.
Aquatic weed control consists of three methods: biological, mechanical, and chemical. Since December 2019, with the help of federal and local agencies, the University of Puerto Rico in Rio Piedras and a community-driven initiative led to the introduction of the Cyrtobagous salviniae in Las Curias Reservoir.  This insect is considered an effective biological control agent for S.  molesta.  Simultaneously, community members initiated a mechanical removal campaign using an aquatic harvester. Monthly sampling was conducted to measure physicochemical, biochemical, and biophysical variables in the reservoir in response to the reduction of S. molesta cover. In addition, monthly drone flights were conducted to create orthomosaic maps of the plant coverage over the water surface, as part of the monitoring of the ecosystem health and characterization. Probably the propagation of S. molesta occurred due to eutrophication after an increase in nutrient-rich sewage discharges from septic tanks and faulty sewage pump stations affected by power outages after Hurricane Maria. By 2019, the reservoir was completely covered with S. molesta. It is not until August 2020 that we noticed considerable changes in the reduction of plant density. Upon the reduction of S. molesta coverage, we found increases in the mean of water temperature (+3 Cِ°), dissolved oxygen (+1.4 mg/L), pH (+0.5) specific conductance (+118.3 µS/cm) and in light penetration (+255.6 μmo/m^2/s).  The water stored in Las Curias could become an invaluable source of raw water for public supply during future droughts, especially in the densely populated San Juan Metropolitan Area, where Las Curias is located. Therefore, its restoration is socially relevant and justifiable. 
On the effect of probabilistic nucleation on the distribution of mineral precipitates in porous media
Authors: Masoudi Mohammad , Nooraiepour Mohammad , Hellevang Helge
Published: March 2022

The process of mineral precipitation and crystal growth begins with nucleation, which is usually overlooked in reactive transport simulators. Nucleation controls the location and timing of solid mineral formation in porous media. For an accurate prediction of the hydrodynamics of the porous medium after mineral precipitation, it is crucial to know the spatial distribution of stable secondary nuclei. We developed a novel probabilistic nucleation approach wherein induction time is treated as a random variable in order to better understand the nucleation process. The probabilistic induction time statistically spreads around the measured or reported induction time, either obtained from experiments or approximated by the exponential nucleation rate equation suggested by the classical nucleation theory (CNT). In this study, we used the classical nucleation theory. The location and time of nucleation are both probabilistic in our model, affecting transport properties at different time and length scales.

We developed a pore-scale Lattice Boltzmann reactive transport model incorporated with the new probabilistic nucleation model to investigate the effect of nucleation rate and reaction rate on the extent, distribution, and precipitation pattern of the solid phases. The simulation domain is a 2D substrate with an infinite source of the supersaturated solution. We use Shannon entropy to measure the disorder of the spatial mineral distributions. The results of the simulations show that all the reactions follow similar random behavior with different Gauss-Laplace distributions. The simulation scenarios start from a fully ordered system with no solid precipitation on the substrate (entropy of 0). Entropy starts to increase as the secondary phase precipitates and grows on the surface until it reaches its maximum value (entropy of 1). Afterward, the overall disorder declines as more surface areas are being covered, and eventually, entropy approaches a constant value. The results indicate that the slower reactions have longer windows of the probabilistic regime before entering the deterministic regime. The outcomes provide the basis for implementing mineral nucleation and growth for reactive transport modeling across time-scales and length-scales.
Deglacial to Holocene changes in sediment characteristics and provenance in core GeoB22336-4 from Lancaster Sound Trough Mouth: Implications for environmental conditions in northwestern Baffin Bay
Authors: Okuma Emmanuel , Titschack Jürgen , Weiser Jens , Kienast Markus , Vogt Christoph , Hebbeln Dierk
Published: March 2022

The Lancaster Sound is currently one of the pathways for Arctic water and ice entering Baffin Bay. However, this gateway was blocked by the coalescing Laurentide and Innuitian Ice Sheets during the Last Glacial Maximum and only opened during the early Holocene after the various ice sheets had retreated (Dyke et al., 2002; Dalton et al., 2020). Core GeoB22336-4 is a well radiocarbon-dated sediment record from the Lancaster Sound Trough Mouth. Sedimentological and geochemical (elemental and mineralogical) properties of this core revealed four major units: (i) the deglacial unit (~14.5 – 9.7 ka BP) with a dense, foraminifera-free, gravel-rich diamict (>14.0 ka BP) that captures proximal ice-margin conditions, probably deposited under an extended thick ice-shelf environment, overlain by rapidly deposited gravel-bearing sandy-silty mud with intercalated turbidite layers reflecting strong input of ice-rafted material and mass wasting, likely resulting from the fast landward retreat of bordering ice sheets in response to regional warming; (ii) the early Holocene unit (~9.7 – 8 ka BP) characterized by a drop in sedimentation rate and the absence of ice-rafted material and reduction in detrital carbonates, suggesting a switch from tide-water to predominately land-terminating glaciers during glacial retreat; (iii) the unit deposited contemporaneously with the regional Holocene Optimum (~8 – 5.9 ka BP; Ledu et al., 2010; Jennings et al., 2011; St-Onge & St-Onge 2014) consists of rapidly deposited rather fine-grained sediments (up to 52 cm ka-1) possibly related to enhanced meltwater- and/or sea-ice-driven sediment input; and (iv) the neoglacial unit (<5.9 ka BP) with reduced sedimentation rates, a sediment provenance switch from calcite-dominated to dolomite-dominated detrital carbonates, and an increased organic matter flux to the seafloor, which led to a four-fold increase in bioturbation. This diverse sedimentary record reflects the complex ice-ocean-atmosphere interactions controlling the sedimentary dynamics and sediment provenance in northwestern Baffin Bay from the last deglaciation through the Holocene. It sheds light on the complex interaction between sediments delivered by local meltwater sources, mass wasting, iceberg and sea ice-rafting, the opening of the Arctic gateways through Lancaster Sound and Nares Strait, and the influence of warm Atlantic Water (AW). In addition, the Arctic Oscillation (AO) possibly governs surface waters and primary production in northern Baffin Bay including the development and extension of the North Water Polynya (NOW).
Effect of temperature on post-earthquake landsliding near the epicentre of the 2008 Wenchuan earthquake
Authors: Loche Marco , Scaringi Gianvito , Yunus Ali P. , Catani Filippo , Tanyaş Hakan , Frodella William , Fan Xuanmei , Lombardo Luigi
Published: March 2022

Geostatistical models of landslide susceptibility do not usually account for thermal data, although these data are widely available, and experiments demonstrate that temperature does influence the mechanical and hydraulic behaviours of soils and rocks via a variety of thermo-hydro-mechanically coupled processes.

We took the epicentral region of the 2008 Wenchuan earthquake in China as our study area, for which a rich multi-temporal inventory of landslides is available. We built a landslide susceptibility model using a generalised additive model with a slope-unit partitioning of the area (~500 km2, comprising 42 sub-catchments), and a minimal set of covariates, including the map of peak ground acceleration of the mainshock and Landsat 7 land surface temperature (LST) data retrieved from Google Earth Engine.

We demonstrated that the LST relates to the decay of post-earthquake landslide activity, and in particular that warmer slopes seems to be comparatively more affected by prolonged landsliding. We also verified that LST data provided different insight from that offered by the normalised difference vegetation index (NDVI), by running our model with NDVI maps instead of LST maps. The two input maps showed little collinearity, and the variable effects of the NDVI in the model output showed less complexity compared to those of the LST. This hints at the presence of thermo-mechanical effects in slopes in addition to the known hydrological effects, the latter being associated with changes in evapotranspiration and thus in principle capturable by the NDVI.

Even though studies in other regions, seismic and non-seismic, are necessary, we suggest that thermal data should be used in landslide susceptibility modelling more systematically because they could potentially improve the model results and suggest physically-based relationships influencing slope stability.