bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-planar dynamic rupture modelling across diffuse, deforming fault zones using a spectral finite element method with a non-mesh aligned embedded diffuse discontinuity
Authors: Hayek Valencia Jorge Nicolas , May Dave A. , Gabriel Alice-Agnes
Published: March 2021

Faults in earthquake rupture dynamic simulations are typically treated as infinitesimally thin planes with distinct on- versus off-fault rheologies. These faults are prescribed and can be explicitly accounted for with hexahedral or unstructured tetrahedral meshing approaches.  
We present a diffuse interface alternative to dynamic rupture modelling on non-mesh aligned faults and, by design, permits modelling of non-planar faults and time-dependent fault geometries. We use se2dr, a spectral finite element (continuous Galerkin) method with a non-mesh aligned embedded diffuse discontinuity for dynamic rupture simulations.

Natural fault systems are characterised by fault zone complexity, e.g. the frictional strength and spatio-temporal slip localisation may change drastically from the outer damage zone to the fault core. Complex volumetric failure patterns are observed in well-recorded large complex earthquakes (e.g., the 2016 Mw7.8 Kaikōura event, Klinger et al. 2018), small events (e.g.,  in the San Jacinto Fault Zone, Cheng et al. 2018), and laboratory-scale experiments (e.g., in high-velocity friction experiments, Passelègue et al., 2016).

We develop a diffuse description of fault slip to better understand complex volumetric failure patterns and the mechanics of slip in diffuse fault zones. The fault is defined via a signed distance function (s(x)), which is in turn used to define a fault indicator function with compact support H. If s(x) > H the material behaves as a pure elastic solid - otherwise the tangential stress is governed by a frictional sliding law.
Our approach is implemented on a structured hexahedral mesh using a spectral finite element (continuous Galerkin) method for wave propagation using PETSc. Our diffuse fault SEM method is inspired by the stress-glut method of Andrews, 1999.  A non-mesh aligned embedded diffusive discontinuity allows for complex dynamic rupture simulations. We present 2D numerical experiments of kinematically driven rupture and spontaneous dynamic rupture on non-planar and non-mesh aligned complex fault geometries. The method can be used to model earthquake rupture dynamics on specifically complex and evolving fault faults such as the San Jacinto, CA, fault, or shallowly dipping megathrusts and splay faulting structures in subduction zones.
Risk of Ground Movement in Faridabad, India – Investigated using Remote Sensing and In-Situ Data
Authors: Garg Shagun , Karanam Vamshi , Motagh Mahdi , Jayaluxmi Indu
Published: March 2021

Land surface elevation changes can cause damage to infrastructure and other resources; thus, its monitoring is crucial for the safety and economics of the city. Long-term excessive extraction of underground water is one of the factors that causes ground to sink. Faridabad, the industrial hub of Haryana, a state in north India is staring a severe water crisis in the near future and has already been declared as a dark zone with regard to groundwater resources. At many places, the underground water table has dropped more than 150m. The plummeting groundwater levels and the geology of this region make it prone to subsidence.

Continuous monitoring of land surface elevations using traditional surveying techniques can be time-consuming and labor-intensive. Several studies have shown the potential of remote sensing techniques in monitoring the changes in topography to an mm level accuracy. In this study, we used the elevation change map (derived using 200+ sentinel -1 images), subsidence gradient, groundwater in-situ data, population, population density, land cover, and lithology. These information were then processed and analyzed in a geographical information system to perform a hazard vulnerability and risk assessment. The final risk map was classified into three different classes viz high, medium, and low risk pertaining to ground movement.

The results indicate that the high-risk zone covers an area of more than 2.5 square kilometers. New Industrial Town (NIT) in Faridabad with an estimated population of more than 1.5 million, is found to be at high risk of ground movement. Groundwater levels in this area are currently depleting by more than 5m/year. Some other areas which are under high risk are the Dabua colony, Sanjay Gandhi Memorial Nagar, and Gandhi colony. All these regions have a high population density and demand urgent government attention.
Why switchbacks may be related to solar granulation 
Authors: Fargette Naïs , Lavraud Benoit , Rouillard Alexis , Réville Victor , Phan Tai , Bale Stuart D. , Dudok De Wit Thierry , Froment Clara , Kasper Justin , Halekas Jasper S. , Louarn Philippe , Case Anthony W. , Korreck Kelly E. , Larson Davin E. , Malaspina David , Pulupa Marc , Stevens Michael L. , Whittlesey Phyllis L. , Berthomier Matthieu
Published: March 2021

Parker Solar Probe data below 0.3 AU have revealed a near-Sun magnetic field dominated by Alfvénic structures that display back and forth reversals of the radial magnetic field. They are called magnetic switchbacks, they display no electron strahl variation consistent with magnetic field foldings within the same magnetic sector, and are associated with velocity spikes during an otherwise calmer background. They are thought to originate either at the photosphere through magnetic reconnection processes, or higher up in the corona and solar wind through turbulent processes.

In this work, we analyze the spatial and temporal characteristic scales of these magnetic switchbacks. We define switchbacks as a deviation from the parker spiral direction and detect them automatically through perihelia encounters 1 to 6. We analyze the solid angle between the magnetic field and the parker spiral both over time and space. We perform a fast Fourier transformation to the obtained angle and find a periodical spatial variation with scales consistent with solar granulation. This suggests that switchbacks form near the photosphere and may be caused, or at least modulated, by solar convection.
Submarine Groundwater Discharge: The invisible mechanism that degrades the quality of crystalline bathing water in the Balearic Islands
Authors: Alorda-Kleinglass Aaron , Ruiz-Mallen Isabel , Diego-Feliu Marc , Rodellas Valentí , Gracia-Orellana Jordi
Published: March 2021

Coastal environments have experienced a rapid transformation due to the expansion of tourism. This growth may enhance problems as over-saturation of spaces or environmental pollution. One of the main problems is associated with the collapse of environmental infrastructures, which may become saturated during high seasons. Indeed, wastewater treatment plants (WWTP) can be located in coastal areas delivering high concentrations of nutrient effluents into the marine environment. Alternatively, WWTP effluents are introduced into coastal aquifers via injection wells, given that the geological matrix is used to filter naturally the transported effluent solutes. However, the injection of significant amounts of WWTP effluents can modify the hydrogeological dynamics and enrich substantially the solute concentrations in groundwaters. Zones with a hydraulic connection between the coastal aquifer and the sea, these contaminated groundwaters may be transferred to coastal environments via Submarine Groundwater Discharge (SGD). Thus, SGD may act as a pathway delivering part of the WWTP-derived nutrients and pollutants into the marine environment, which may lead to eutrophication or harmful algal blooms. More importantly, such process may become threatening for society when the discharge occurs into bathing waters, affecting the ecosystem and perception of stakeholders.

In this study, we evaluate the role of SGD as a conveyor of nutrients from a karstic coastal aquifer affected by the injection of WWTP effluents to the Deià cove in Mallorca (Balearic Islands). Results show that the tourism seasonality changes the coastal aquifer natural dynamics during the dry season, delivering via SGD, nutrients concentrations above the maximum limits established by the Spanish and European water framework directives. Due to those enriched nutrient fluxes, the coastal water ecosystem has registered the highest values of ∂15N in Posidonia oceanica in the Balearic Islands and suffers periodic algal blooms, creating a conflict among stakeholders.
Monitoring the plasmapause dynamics at LEO
Authors: Heilig Balázs , Stolle Claudia , Rauberg Jan , Kervalishvili Guram
Published: March 2021

In the past decades researchers have revealed links between a series of sub-auroral ionospheric phenomena and the plasmapause (PP) dynamics, such as the mid-latitude ionospheric trough (MIT) and the associated sub-auroral temperature enhancement (SETE), the light-ion trough (LIT), the sub-auroral ion drift (SAID) or the more intense sub-auroral polarisation stream (SAPS), and most recently, the inner boundary of small-scale field-aligned currents (SSFACs). Most of these phenomena can be directly observed by the Swarm constellation of ESA at LEO. Thus, Swarm presents a unique opportunity to study the relations between them and also their relation to the PP dynamics.

In a recent Swarm DISC project, PRISM (Plasmapause Related boundaries in the topside Ionosphere as derived from Swarm Measurements), three new products have been developed. Two products characterise the MIT (and the associated SETE). The MITx_LP utilises the Langmuir probe measurements of electron density and temperature, while the MITxTEC product derives the MIT properties from GPS TEC observations. The third product, PPIxFAC provides information on the location and the main characteristics of the equatorial boundary of SSFACs, and it also includes a proxy for the location of the PP at MLT midnight.

In this presentation we introduce the above Swarm L2 products, present the results of a comparative study aiming at revealing their mutual relations and also their dynamic coupling to the PP. Then we demonstrate how the observations of all these ionospheric phenomena combined can be used to develop an improved proxy for monitoring the PP dynamics at LEO as one of the goals of our new ESA-funded project PLASMA.
Influence of coastal upwelling on the surface current in the Bay of Bengal using HF radar and satellite observations
Authors: Dey Shouvik , Sil Sourav , Mandal Samiran
Published: March 2021

Coastal Upwelling is a phenomenon in which cold and nutrient-enriched water from the Ekman layers reaches the surface enhancing the biological productivity of the upwelling region. In this work, an attempt is made to understand the influence of coastal upwelling on surface current variations during May 2018 to August 2018, when HF radar current observation (source: NIOT, India) is available. The wind-based Upwelling Index(UIwind) showed coastal upwelling throughout the study period. But the SST based upwelling index (UIsst) showed upwelling occurred only from May to the first week of June. Cross-shore components of HF radar-derived ocean surface current (CSSC)  showed strong similarity with UIsst. The first phase of upwelling from UIsst is observed to start on 5th May and lasts till 14th May with a maximum peak on around 10th May and having a horizontal extension of ~40 km. Then, there is a break period for about three days and after that, the second phase of upwelling starts on 17th May and lasts till 25th May with a maximum peak on around 20th May, but this time the horizontal extension is ~100 km which is much larger than during the first phase. A strong positive (from coast to offshore) CSSC is observed to start on around 5th May and lasts till 13th May with a maximum peak on around 10th May and having a horizontal extension of ~40 km, as observed from UIsst. A reversal of CSSC (towards coast) is noted on 14th May when the break of coastal upwelling is evident from UIsst. The CSSC then again started intensifying 15th May onwards and continued for ten days till 25th May, similar to UIsst.  The horizontal extension of the upwelling signature in the second phase of upwelling is ~70 km. Therefore, a 7-10 days of the coastal upwelling and its horizontal extension are identified in this study. This study suggests the use of high resolution (~6 km) HF radar current observation on the monitoring of coastal upwelling processes.
Continuous flow analysis of the Mount Brown South ice core
Authors: Harlan Margaret , Kjær Helle Astrid , Vance Tessa , Vallelonga Paul , Gkinis Vasileios , Blunier Thomas , Svensson Anders , Moy Andrew , Plummer Chris , Jackson Sarah , Peensoo Kerttu , de Campo Aylin
Published: March 2021

The Mount Brown South (MBS) ice core is an approximately 300-meter-long ice core, drilled in 2016-2017 to the south of Mount Brown, Wilhelm II Land, East Antarctica. This location in East Antarctica was chosen as it produces an ice core with well-preserved sub-annual records of both chemistry and isotope concentrations, spanning back over 1000 years. MBS is particularly well suited to represent climate variations of the Indian Ocean sector of Antarctica, and to provide information about regional volcanism in the Southern Indian Ocean region.

A section of ice spanning the length of the MBS core was melted as part of the autumn 2019 continuous flow analysis (CFA) campaign at the Physics of Ice, Climate, and Earth (PICE) group at the University of Copenhagen. During this campaign, measurements were conducted for chemistry and impurities contained in the ice, in addition to water isotopes. The data measured in Copenhagen include measurements of H2O2, pH, electrolytic conductivity, and NH4+, Ca2+, and Na+ ions, in addition to insoluble particulate concentrations and size distribution measured using an Abakus laser particle counter.

Here, we present an overview of the CFA chemistry and impurity data, as well as preliminary investigations into the size distribution of insoluble particles and the presence of volcanic material within the ice. These initial chemistry and particulate size distribution data sets are useful in order to identify sections of the MBS core to subject to further analysis to increase our understanding of volcanic activity in the Southern Indian Ocean region.
Paleoenvironmental reconstruction of the central Levantine Corridor during the Pliocene: insights from lacustrine settings 
Authors: Greenlee John , Dean Silas , Waldmann Nicolas
Published: March 2021

This study aims to reconstruct the paleoenvironmental and climatic conditions affecting the Levantine corridor during the early Pliocene. For the purpose of this study, a ~20 m continuous core sequence was retrieved out of the ~200 m long, tilted Erk el Ahmar sequence previously dated by cosmogenic isotopes to ~3.5 Ma. The record include intercalating units consisting of sands, silts, and clays that were sampled in high resolution in order to analyze a variety of sedimentological and geochemical proxies of past climate and environmental changes. We present new preliminary, high-resolution sedimentological (laser diffraction granulometry), petrophysical (magnetic susceptibility) and compositional (X-ray fluorescence) data along with accompanying statistical analysis performed with an advanced suite of data-science tools. These results reveal new cycles of environmental change in the area, which appears to be orbitally controlled, and include dramatic changes also indicated by discrete strata of fossil fragments. Moreover, cycles of deposition can also provide hints on the major hydrological controlling mechanisms. This project provides new light into favorable conditions for the subsistence of perennial lake environments in the Levantine Corridor, which in turn may have facilitated faunal migration between Africa and Eurasia.
Are carbonates from the India-Asia collision remagnetized ? 
Authors: Roperch Pierrick , Dupont-Nivet Guillaume
Published: March 2021

Widespread carbonate rocks from the Tibetan plateau have been extensively used to constrain terrane paleolatitudes involved in the India-Asia collision. However, their reliability in preserving a primary magnetization has been recently put into question.  A transformation of pyrite to magnetite has been recently proposed as a cause for late re-magnetizations in Paleocene Tethyan Himalaya carbonates (1) and late Triassic carbonates from the Qiantang (2), thus discarding such Characteristic Remanent Magnetizations (ChRM) for tectonic purposes. We have re-examined the paleomagnetic data obtained on late Triassic carbonate rocks from the Qiantang. Our SEM observations indicate pristine pyrite in non-weathered carbonate rocks. Optical microscope observations in reflected light demonstrate that pyrite, when it is weathered, is transformed to iron hydroxides minerals but not to magnetite. This is at odds with previously proposed pyrite to magnetite transformation hypothesis mainly based on interpretations of Scanning Electron Microscope data (SEM/EDS). We thus interpret the ChRM more likely related to an early diagenetic magnetization of Late Triassic age. Knowing that the arguments put forward for a remagnetization of Triassic carbonates are the same as those proposed for the remagnetization of Paleocene carbonates, the ChRM in some Paleocene carbonates could also be of early diagenetic origin. However, there is also a growing number of studies where remagnetization is obvious in the Tethyan Himalaya and undetected remagnetizations (3) are likely the cause of the large differences in the estimation of the size of Greater India. These examples show the urgent need to publish the complete demagnetization dataset in an open database like MAGIC or the FAIR data initiative from (4) in order to reassess previous interpretations if we want to solve problems like the size of Greater India and hypothesis like the Greater India basin.

(1) doi:10.1002/2016JB013662 ; (2) doi:10.1016/j.epsl.2019.06.035 ; (3) doi:10.1016/j.epsl.2020.116330; (4) doi:10.1029/2019GC008838.

 
Distinct diurnal formation processes of organic aerosols in winter in Beijing, China
Authors: Ma Tao , Furutani Hiroshi , Duan Fengkui , Kimoto Takashi , Ma Yongliang , Zhu Lidan , Huang Tao , Toyoda Michisato , He Kebin
Published: March 2021

Organic aerosols (OA) are major components of fine particulate matter, yet their formation mechanism remains unclear, especially in polluted environments. Laboratory studies have shown that the OA formation processes may be different under irradiated and dark conditions, but few studies have explored this aspect in ambient air. Here we investigate the diurnal chemical composition and formation processes of OA in carbonaceous particles during winter in Beijing using aerosol time-of-flight mass spectrometry. Our results show that 84.5% of carbonaceous particles undergo aging processes, characterized with larger size and more secondary species compared to fresh carbonaceous particles, and present different chemical compositions of OA in the daytime and nighttime. During the day, organosulfates and oligomers exist in the aged carbonaceous particles, which are mixed with a higher abundance of nitrate compared with sulfate. At night, distinct spectral signatures of hydroxymethanesulfonate and organic nitrogen compounds, and a minor abundance of other hydroxyalkylsulfonates and high molecular weight organic compounds are present in the aged carbonaceous particles, which are mixed with a higher abundance of sulfate compared with nitrate. Our results indicate that photochemistry dominates the formation of OA under high oxidant concentrations in the daytime, while aqueous chemistry plays an important role in the formation of OA under high relative humidity in the nighttime. The findings can help improve the performance of air quality and climate models on OA simulation.
The Role of Diagenesis in the Apparent Rise of Diatoms
Authors: Westacott Sophie , Planavsky Noah , Zhao Ming-Yu , Hull Pincelli
Published: March 2021

Diatoms are one of the most dominant primary producers in the ocean today and largely control the modern marine silica cycle. Their ecological expansion in the Cenozoic is thought to have lowered silica concentrations by two orders of magnitude and has been linked to the rise of grasslands and baleen whales. According to the fossil record much of diatoms' rise to dominance occurred in the past 20 m.y.; however, silicon isotope evidence suggests an earlier expansion. Using a diagenetic model and collated deep sea drill core data, we examine how changes in bottom-water temperature and sedimentation rates over the past 65 m.y. affected the burial efficiency of biogenic silica. We find that once taphonomic potential is taken into account there is no support for the traditionally recognized ~5-20 Ma increase in diatom abundance. These results help reconcile interpretations based on geochemical and fossil data, and add to mounting evidence pushing back the evolution of the modern silica cycle to before 20 Ma and possibly earlier than 40 Ma.
Hybrid mineral predictive mapping with self-organizing maps and a multilayer perceptron applied to tin deposits in the Erzgebirge, Germany
Authors: Brosig Andreas , Barth Andreas , Hielscher Peggy , Legler Claus , Schäfer Stefan , Bock Peter , Knobloch Andreas
Published: March 2021

Self-organizing maps (SOM) are a useful tool to analyze and interpret gridded datasets like potential field or stream sediment geochemistry data. The data are transformed from geographic space to SOM space where they can be clustered according to overall similarity. By transforming the clusters back to geographic space, geological interpretation of the clusters is facilitated. We present the application of a multilayer perceptron (MLP) in SOM space to produce mineral predictive maps. The reduced number of grid cells in SOM space greatly enhances the performance of the MLP and the tolerance to noise in the input data, compared to an application of the MLP to the original data. The method is applied to tin skarn deposits in the German part of the Erzgebirge. The training and validation data required for the MLP are compiled from mining and exploration records. The input data for the SOM are reprocessed gravimetric, magnetic, stream sediment geochemistry, geologic and tectonic data sets. Potentially ore-controlling spatial relationships, such as the distance to different types of partly covered granite intrusions, are derived from a regional scale 3D geological model. The resulting mineral prediction map allows the definition of exploration zones for detailed studies.

The paper has been compiled in the frame of "NEXT - New EXploration Technologies" project. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 776804.
Historical record and sources of contaminants in sediments from Mar Menor coastal lagoon.
Authors: Alorda-Montiel Irene , Rodríguez-Puig Júlia , Alorda-Kleinglass Aaron , Diego-Feliu Marc , Rodellas Valentí , Garcia-Orellana Jordi
Published: March 2021

Mar Menor (SE, Spain) is one of the largest coastal lagoons in the Mediterranean basin. Its ecological and economic significance has led to its inclusion in several protection programmes, both on a national and international level. In the last decades, this semiconfined habitat has been under high anthropogenic pressure from agricultural, mining and tourism activities, which have resulted in significant changes, such as eutrophic events and their cascading ecological effects. Previous research suggests that this degradation is linked to the introduction of nutrients and contaminants to this ecosystem, which are accumulated in the sediments of the lagoon. In this work, sediment cores from key locations of the Mar Menor were collected in order to estimate the amount of accumulated chemical compounds, such as metals and organic compounds. The results of this study are used to reconstruct the historical record of contaminants, which can fuel future contamination episodes in the lagoon.  

  
Diatoms in Ice Cores, a new proxy for reconstructing past wind strength in the Amundsen-Bellingshausen Seas region, Antarctica
Authors: Tetzner Dieter , Thomas Liz , Allen Claire
Published: March 2021

In the last decade, several efforts have been carried out to assess the causes of the current rapid recent warming measured on West Antarctica and Antarctic Peninsula. The increase in wind strength and shifts in atmospheric circulation patterns have shown to play a key role in driving the advection of warm air from mid-latitudes to high-latitudes. Winds are also responsible for driving surface melting in the ice shelves, enhancing the removal of surface snow, and for promoting basal melting through the upwelling of deep warm water. All these combined have shown to produce substantial effects on environmental parameters, such as sea surface temperatures, sea ice extension, air surface temperatures and precipitation.

Even though winds are fundamental components of the climatic system, there is a lack of reliable long-term observational wind records in the region. This has hindered the ability to place the recent observed changes in the context of a longer time frame.

In this work, we present annual and sub-annual records of marine diatoms preserved in a set of ice cores retrieved from the southern Antarctic Peninsula and Ellsworth Land region, Antarctica. The diatom abundance and species assemblages from these ice cores prove to represent the local/regional variability in wind strength and circulation patterns that influence the onshore northerly winds.  The spatial distribution of these ice cores enabled to identify regional trends (coastal/inland) and to validate the proxy across the region. Our findings highlight the potential this novel proxy to produce an annual reconstruction of westerly winds in the Amundsen - Bellingshausen seas region.

 
Geological mapping of carbonatites and related ores from the Oulad Dlim massif (Dakhla Province, Morocco) using remote sensing, portable X-ray fluorescence, and mineralogical data
Authors: Malainine cheikh elwali , Raji Otmane , Ouabid Muhammad , Khouakhi Abdou , Bodinier Jean-Louis , Parat Fleurice , El Messbahi Hicham
Published: March 2021

During the last decades, carbonatites and associated rocks have received increased interest from mining companies and the scientific community. They represent a classic source of a variety of critical elements required by certain emerging technologies and industries such as niobium, rare earth elements (REE), and phosphorus. Morocco like many other countries have several Alkaline igneous complexes, however, their potential in terms of REE-P-rich carbonatites is poorly explored and needs to be investigated. This study is an attempt to develop an advanced exploration tool for the detection and mapping of these rocks using remote sensing.  Preliminary investigations were focused on the Oulad Dlim massif at the western Reguibat Shield (Southeast of Dakhla province) where several carbonatite structures were reported, including Gleibat Lafhouda, Twihinate, Lamlaga, Lahjayra. Advanced Spaceborne Thermal and Reflection Radiometer (ASTER) data were used to: (i) identify and map carbonatites and associated rocks liable to contain REE-P mineralization, (ii) investigate their spectral features, and produce predictive maps. Several image processing techniques, have been performed including band ratio, color composite image, principal component analysis and minimum noise fraction. The combination of these techniques appears to more effectively detect carbonatites and associated rocks. The effectiveness of this approach was verified using field investigation, in-situ geochemical analysis with portable X-ray fluorescence, and petrography. The field data were used to train classifiers to better delineate the spatial distribution of the different lithological facies. The results are generally consistent with available geological maps indicating that this approach can be satisfactorily applied in the early stages of geological exploration.
Real Time Magnitude Classification of Earthquake Waveforms using Deep Learning
Authors: Chakraborty Megha , Rümpker Georg , Stöcker Horst , Li Wei , Faber Johannes , Fenner Darius , Zhou Kai , Srivastava Nishtha
Published: March 2021

This study attempts to use Deep Learning architectures to design an efficient real time magnitude classifier for seismic events. Various combinations of Convolutional Neural Networks (CNNs) and Bi- & Uni-directional Long-Short Term Memory (LSTMs) and Gated Recurrent Unit (GRUs) are tried and tested to obtain the best performing model with optimum hyperparameters. In order to extract maximum information from the seismic waveforms, this study uses not only the time series data but also its corresponding Fourier Transform (spectrogram) as input. Furthermore, the Deep Learning architecture is combined with other machine learning algorithms to generate the final magnitude classifications. This study is likely to help seismologists in improving the Earthquake Early Warning System to avoid issuing false warnings, which not only alarms people unnecessarily but can also result in huge financial losses due to stoppage of industrial machinery etc.
MOSAiC simulator in CMIP6
Authors: Juhrbandt Rajka , Cheedela Suvarchal , Koldunov Nikolay , Jung Thomas
Published: March 2021

The recently completed Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) can serve as reference to evaluate current and future ocean state of the Arctic Ocean. With this premise, we perform a virtual MOSAiC expedition in historical and ssp370-scenario experiments in data generated by CMIP6 models.

The timespan covered ranges from preindustrial times (1851-1860) through present-day up to a 4K world (2091-2100). Early results using AWI-CM model, suggest that for scenario simulations a thinning of the colder surface layer and a warming of the layer between 200 and 1200 m along the MOSAiC path can be expected, while there is no significant change in temperature below this depth. Results from other models will be presented.

The Python-centric tool used for the analysis simplifies preprocessing of a pool of CMIP6 data and selecting data on space-time trajectory. It exposes an interface that is agnostic to underlying model or its grid type. Code snippets are presented along to demonstrate the tool's ease of use with a hope to inspire such virtual field campaigns using other past observations or arbitrary trajectories.
Continuous surveillance of UK coastline using EO data to monitor coastal change impact
Authors: Jones Martin , Payo. Garcia Andreas
Published: March 2021

The UK coast is under  increasing risk due to coastal change, cliffs are collapsing endangering houses near the coast and of the 12,400 km of  coastline, 2,500 km present a flooding risk. Constant monitoring is necessary in order to keep coastal evolution under surveillance and to adapt the measures to mitigate the impact of coastal change. Earth Observation technology is unique in that it has now been available for over 25 years and currently there is a range of satellites both civil and commercial that are constantly viewing our coast. Satellite imagery provides large scale observation at a high spatial resolution with an average revisit time of 5 days for most missions. Temporal and spatial resolution are key components to provide a continuous monitoring service of a coast. Using the balance of ever increasing resolution coupled to a range of innovative techniques that make full use of the spectral signatures being captured enables us to recreate the coastal boundary to a high degree of reliability over complete national coastlines.

Our developed methodology combines different types of products to completely characterize the different coastal environments. The land/sea boundary is used to monitor changes along the coast and combine with a backshore land use, land cover classification map, we are able to bring contextual information on coastal vulnerability and their erosive potential. Our LiuJezek_CoastL processor extracts the instantaneous land/sea boundary from all satellite observations available and provides a vector line which represents the coast morphology depending on sea level at the time of the acquisition. This line is then corrected from all water dynamics such as waves, tidal level to create shorelines at a reference datum height. The error in positioning the shoreline is relaint on beach slopes, for example in the case of cliffs or civil works along the coast compared to long shelfing beaches. Our backshore classification, provides land use and land cover information which can correct the shoreline position according to the features present along the coast.
Experimental access to Volcanic Eruptions and their role in the Earth System. 
Authors: Dingwell Donald B.
Published: March 2021

Few things are more central to earth history, planetary evolution and the earth system, than volcanism. Explosive volcanism in particular exhibits individual events whose impact can range from local to global. Developing a mechanistic understanding of the inner workings of volcanic systems is essential for understanding their behavior and modelling their impact. Experiments form a fundamental part of our modern scientific approach to volcanic research, an approach which relies heavily on materials characterisation. In the year 2021, we can look back on decades of  novel and highly innovative experimental approaches applied to the investigation of volcanic processes. The focus has ranged from pre-eruptive and eruptive dynamics  all the way to the fate  and importance of volcanic materials in the Earth System. The applied aspects of the work reach, for example, into eruption forecasting, hazard mapping and aviation safety. I will attempt portray the the long term strategy of the approach we have taken as well as providing comments on the likelihood of certain further developments in the near future.
Fire impact on water and carbon fluxes in a wild olive-based ecosystem
Authors: Curreli Matteo , Montaldo Nicola , Corona Roberto , Katul Gabriel G.
Published: March 2021

Fire, harvesting and beetles attacks are important disturbances for the forested ecosystems. The aim of this study is to examine the impact of the disturbances on water and carbon fluxes using a eddy‐covariance (EC) – based tower in a wild-olive forest.

The study has been performed at the Orroli site, Sardinia (Italy), which is an experimental site for the FLUXMED project of the Water Joint Programming Initiative. From 2003, a 10 m micrometeorological tower equipped with eddy-covariance system has been used to measuring water, carbon and energy surface fluxes, as well as key state variables (e.g. leaf and soil skin temperature, radiations, air humidity and wind velocity).

The landscape is covered by patchy vegetation: wild olives trees in clumps and herbaceous species, drying to bare soil in late spring. The climate is Mediterranean maritime with long droughts from May to October, and rainy period is concentrated in the autumn and winter months. In this ecosystem water uptake by olive’s roots, from underlying substrate to the shallow soil layer, allow woody vegetation and grass to remain physiologically active during dry conditions.

In summer 2017, which was a very dry season, an extended fire affected the forested area, impacting the north – west footprint of the tower, with consequences also to the close trees due to beetle attack, probably related to the sensitive conditions of the trees after the drought.

We compared pre-disturbance with post-disturbance land surface fluxes. Both fire and beetle attack, altered the partitioning of available energy to lE and H, evapotranspiration (ET) and carbon assimilation. Results show a reduction of evapotranspiration and carbon assimilation during the growing season. Differently, in autumn and winter the difference between pre-disturbance and post-disturbance was negligible due to low physiological activities of vegetation.
Source to Sea – Investigation of Microplastics in an agricultural catchment in Eastern England
Authors: Zieniute Gertruda , Magnone Daniel , Macklin Mark
Published: March 2021

Global plastic demand has led to a growing abundance of microplastics being detected across all environmental compartments. These microplastics pose a long-term health risk to ecosystems through accumulation, ingestion and leaching of chemicals. Knowledge of microplastics in river catchments has been limited due to their complexity, however as microplastics have a terrestrial origin, freshwater systems are considered to be a key pathway to other environments. They can transport microplastics to marine environments, act as temporary and long-term storage and aid degradation of larger plastics into smaller fragments that enter the aquatic system.

As microplastics are linked to anthropogenic sources, much of the focus has been placed on urban and industrial areas, but in this study, we aim to assess a rural, agricultural catchment. River Witham catchment in Eastern England covers the area of 3,000km2 with a population of ~400,000. The river provides important drainage for the high-grade agricultural land in the fens and it discharges into the Wash, which is England’s largest nature reserve as well as an important area for shellfish aquaculture.

This presentation will address the preliminary findings of this project by detailing the spatial variability of microplastics storage in riverbed sediments in an agricultural catchment. Data suggests that microplastic concentration could be as high in rural areas as it is in urban areas. The findings are expected to help improve the knowledge of microplastic contamination on a catchment level and to act as a basis for regional environmental protection.
Comparison of lightning observed by ASIM on the International Space Station and GLM on the GOES-16 geostationary satellite
Authors: Dimitriadou Krystallia , Chanrion Olivier , Chaumat Laure , Christian Hugh J. , Blakeslee Richard J. , Heumesser Matthias , Østgaard Nikolai , Reglero Victor , Neubert Torsten
Published: March 2021

The Atmosphere-Space Interactions Monitor includes an optical imaging array consisting of 5 nadir-viewing  sensors , dedicated to monitor electrical discharges in and above thunderstorms. Three photometers sample in 337.0/4 nm, the VUV band 180-230 nm and 777.4/5 nm with a sample rate of 100 kHz while the 2 cameras record in 337.0/3 nm and in 777.4/3 nm with a temporal and spatial resolution of 12 frames per second and ~400 m, respectively. The Geostationary Lightning Mapper (GLM) on the GOES-16 satellite is the first operational space-based lightning detector in geostationary orbit measuring in 777.4/1 nm, with a pixel size of ~8-14 km and temporal resolution of up to 500 frames per second.
We present an analysis of the signal amplitudes and detection efficiencies of ASIM and GLM based on three mutually detected storms: one in the center and two on the edges of GLM field of view. We find a dependence of the amplitudes and detection efficiencies on the cloud structure and the observation angles of ASIM and GLM. The best agreement between the instruments appears when ASIM detects towards the nadir, but differences in amplitudes may vary by several orders of magnitude.  The cloud structure offers a potential explanation for these differences which we will explore in the presentation.
Island's topography effects on the meso-to-large-scale circulation of the Gulf of Guinea
Authors: Napolitano Dante , Alory Gael , Jouanno Julien , Morel Yves , Dadou Isabelle , Morvan Guillaume
Published: March 2021

In the northeast Gulf of Guinea (GG), São Tomé island marks the beginning of an SW-NE oriented island chain that stretches from near the equator, in the path of the Equatorial Undercurrent (EUC), to the innermost portion of the GG, where its largest island, Bioko, rises at the edge of Cameroon's continental shelf. This region of scarce observations is randomly sampled by surface drifters, which are seldom deployed elsewhere and reach GG carried by eastward equatorial currents. Curiously, the trajectories of these eastward-floating drifters approaching São Tomé veer toward the northeast, ending up in the vicinity of Nigeria, at about 4 °N. Motivated by these trajectories, we investigate the influence of the island chain's topography in the (sub)meso-to-large-scale circulation of the zonal equatorial jets. We ask: (i) does the island chain presents a physical barrier that drives the flow until the inner parts of GG? (ii) are there submeso and mesoscale anomalies generated due to flow-topography interactions?, and (iii) can these anomalies upscale to alter large scale currents, such as the EUC? We analyze the outputs of two NEMO simulations, which differ only by the presence/absence of the islands and their associated rough topography. We run both simulations with 1/12° horizontal resolution, using the same initial conditions. We will show a comparison of both simulations with moored observations (from the PIRATA array), analyzes of particle trajectories in both scenarios (i.e., with and without islands), and the differences in the large-scale equatorial currents depicted from both model runs.
Chemotaxis under flow disorder shapes microbial dispersion in porous media 
Authors: de Anna Pietro , Pahlavan Amir A. , Yawata Yutaka , Stocker Roman , Juanes Ruben
Published: March 2021

Natural soils are host to a high density and diversity of microorganisms, and even deep-earth porous rocks provide a habitat for active microbial communities. In these environ- ments, microbial transport by disordered flows is relevant for a broad range of natural and engineered processes, from biochemical cycling to remineralization and bioremediation. Yet, how bacteria are transported and distributed in the sub- surface as a result of the disordered flow and the associ- ated chemical gradients characteristic of porous media has remained poorly understood, in part because studies have so far focused on steady, macroscale chemical gradients. Here, we use a microfluidic model system that captures flow disorder and chemical gradients at the pore scale to quantify the transport and dispersion of the soil-dwelling bacterium Bacillus subtilis in porous media. We observe that chemotaxis strongly modulates the persistence of bacteria in low-flow regions of the pore space, resulting in a 100% increase in their dispersion coefficient. This effect stems directly from the strong pore-scale gradients created by flow disorder and demonstrates that the microscale interplay between bacterial behaviour and pore-scale disorder can impact the macroscale dynamics of biota in the subsurface.
Assessing Geo-hazard Vulnerability of Cities and Critical Infrastructures: Working in the e-Shape Framework
Authors: López-Vinielles Juan , Ezquerro Pablo , Herrera-García Gerardo , Béjar-Pizarro Marta , Comerci Valerio , Sheehy Michael , Poyiadji Eleftheria , Koçiu Arben , Mikulėnas Vidas , Jemec-Auflič Mateja
Published: March 2021

To improve safety in large cities, products and services exploiting Earth Observation (EO) technologies can be used to map vulnerable urban areas potentially affected by geohazards, with the aim of reducing human and economic losses caused by natural disasters. This work aims to increase the use of multi-mission EO derived products and services to assess urban vulnerability and geohazards, raising early awareness and training key users and decision makers on the use of EO derived products and services.

Currently, the InSAR processing tools from Geohazards Exploitation Platform (GEP) funded by European Space Agency, provide massive and dense surface displacement information, and availability of such data is expected to be expanded soon with the upcoming European Ground Motion Service being developed by the European Environment Agency. As the main end users are not trained to understand and analyze this type of data, the EU founded e-Shape project, in collaboration with the national Geological Surveys, is introducing a methodology for the use of InSAR products and supporting them to co-design specific products useful for the dissemination of information to the users active in key societal sectors  (local and regional administrations, and civil protection authorities). To this end, four products with different requirements have been developed, including the InSAR map, the InSAR validation report, the active geohazards report and the vulnerable urban areas report. These four products describe the displacements of the area, their accuracy, their relationship to triggers and the potential problems they could create, providing information for both technical staff and non-technical managers and decision-makers.
Radiation and wind projections for Poland based on downscaled EuroCORDEX ensemble
Authors: Struzewska Joanna , Jefimow Maciej , Gienibor Aneta , Kleczek Maria , Sattari Anahita , Zdunek Malgorzata , Norowski Aleksander , Walczak Bartlomiej
Published: March 2021

Forecasted trends of solar radiation and wind speed serve as an input for climate risk assessment as well as the estimation of renewable energy potential in the future climate.

In the frame of the project “Adaption strategies to Climate Change in Poland” the projections of solar radiation and the wind speed were developed based on the EURO-CORDEX. The RCM results for an area covering central Europe with a resolution of 0.11 ° (approx. 12.5 km) were used. The analyses were carried out for RCP4.5 and RCP8.5 scenarios.

 

To represent better the local variability the statistical downscaling was applied based on various historical gridded datasets (ERA5 and IMWM for the wind speed and ERA5, IMWM, and SARAH-II for the shortwave solar radiation). Ensemble analyses were undertaken to assess the projection uncertainty.

Solar radiation in the future climate shows a slight downward trend. The annual sum of solar radiation at the end of the century will decrease by 12 kWh/m2 to 40 kWh/m2, depending on the scenario. The most significant change will occur in eastern and north-eastern Poland. Forecasts of average wind speed values do not indicate significant changes in the 21st century, although the wind speed distribution showed changes in individual months - an increase in the winter and a decrease in the summer months.

Results are available via the interactive climate web portal https://klimada2.ios.gov.pl/klimat-scenariusze-portal/.
Inspection of new thunderstorm intensity index
Authors: Jelic Damjan , Malecic Barbara , Telisman Prtenjak Maja , Belusic Vozila Andreina , Renko Tanja , Megyeri Otília Anna
Published: March 2021

Lightning data provide very high spatial and temporal resolution allowing us to decompose thunderstorms into smaller segments. By using those segments we introduce a new Thunderstorm Intensity Index (TSII). Based on the mathematical background of lightning jump, TSII aims to identify the area which is most affected by the storm. Such index captures location in space and time where a thunderstorm experienced a sudden positive change in lightning activity, using the Eulerian standpoint. The advantage is independence to total number of flashes produced by the storm (which can vary significantly), and high temporal monitoring (2 min). An ongoing research (within SWALDRIC project) is performed on period of 11 years of lightning data and in a study area of NE Adriatic region. Validation is done against precipitation, wind, hail, waterspouts and comparison with ERA5 instability indices is made. Results show very good agreement between higher rain intensities and total precipitation in vicinity of TSII. Good agreement with hail occurrence, waterspout presence and wind gusts within 15km radius. Also, TSII turned to be invariant to the size of the system, thus allowing us to recognise small scale intense thunderstorms.