bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel model independence methodology to improve multi-model seasonal forecasts combination
Authors: Catalano Franco , Alessandri Andrea , Nielsen Kristian , Cionni Irene , De Felice Matteo
Published: March 2020

Multi-model ensembles (MMEs) are powerful tools in dynamical climate prediction as they account for the overconfidence and the uncertainties related to single model ensembles. The potential benefit that can be expected by using a MME amplifies with the increase of the independence of the contributing Seasonal Prediction Systems. To this aim, a novel methodology has been developed to assess the relative independence of the prediction systems in the probabilistic information they provide.

We considered the Copernicus C3S seasonal forecasts product considering the one-month lead retrospective seasonal predictions for boreal summer and boreal winter seasons (1st May and 1st November start dates, i.e. June-July-August, JJA and December-January-February, DJF). We analysed the seasonal hindcasts in terms of deterministic and probabilistic scores with a particular focus on continental areas, since little evaluation has been performed so far over land domains that is where most of the applications of seasonal forecasts are based. The most relevant target variables of interest for the energy users have been considered and skill differences between the prediction systems have been analysed together with related possible sources of predictability. The analysis evidenced the importance of snow-albedo processes for temperature predictions in DJF and the effect of the atmospheric dynamics through moisture convergence for the prediction of surface solar radiation in JJA. A new metric, the Brier Score Covariance, designed to quantify the probabilistic independence among the models, has been developed and applied to optimize model selection and combination strategies with a particular focus on the most relevant variables for energy applications.
Investigation of global atmospheric carbonyl sulphide between 2004 and 2018: an observational and modelling study
Authors: Cartwright Michael P. , Harrison Jeremy J. , Moore David P. , Remedios John J. , Chipperfield Martyn P. , Pope Richard J.
Published: March 2020

The challenge in quantifying the sources and sinks of atmospheric carbon dioxide (CO2) is that the CO2 taken up by plants during photosynthesis cannot be distinguished from the CO2 released by plants and micro-organisms during respiration. It has been shown that carbonyl sulfide (OCS), the sulphur-containing analogue of CO2, can be used as a proxy for photosynthesis. The relationship between the vegetative flux of OCS and CO2 has been quantified for various species of plants and ecosystems, the results of which have been used in observing the relationship on a continental scale. The aim of this project is to both quantify the location and magnitude of the sources and sinks of atmospheric OCS, and to use these data to infer photosynthetic uptake of CO2 by vegetation on a global scale.

A tracer version of the 3-dimensional chemical transport model TOMCAT has been adapted to include eleven different sources and sinks of OCS, including direct and indirect oceanic emissions, vegetative uptake and stratospheric photolysis. The modelled OCS (TOMCAT-OCS) distribution between 2004 and 2018 has been co-located spatially and temporally to OCS profiles measured by the Atmospheric Chemistry Experiment (ACE-FTS) over the 5 – 30 km altitude, showing generally good agreement. Furthermore, surface TOMCAT-OCS has been compared to OCS measurements made at twelve NOAA-ESRL sites, across both hemispheres, showing that the model captures the seasonal cycle at the surface.

There have been several calls in recent years for a new satellite product of atmospheric OCS, which this project aims to satisfy. Work is ongoing to retrieve OCS total columns from measurements taken by the Infrared Atmospheric Sounding Interferometer (IASI) instruments on-board the MetOp satellites. The University of Leicester IASI Retrieval Scheme (ULIRS) has been adapted to retrieve OCS columns globally. Various case studies for different geographic regions and time periods will be presented and compared to other satellite observations.
Northern Hemisphere atmospheric blocking simulation in present and future climate
Authors: D'Andrea Fabio , Davini Paolo
Published: March 2020

We present a comprehensive analysis of the representation of winter and summer Northern Hempishere atmospheric blocking in global climate simulations in both present and future climate. Three generations of climate models are considered: CMIP-3 (2007), CMIP-5 (2012) and CMIP-6 (2019).
All models show common and extended underestimation of blocking frequencies, but a reduction of the negative biases in successive model generations is observed. However, in some specific regions and seasons as the winter European sector, even CMIP-6 models are not yet able to achieve the observed blocking frequency. For future decades the vast majority of models simulates a decrease of blocking frequency in both winter and summer, with the exception of summer blocking over the Urals and winter blocking over Western North America. Winter predicted decreases may be even larger than currently estimated considering that models with larger blocking frequencies  hence generally smaller errors - show larger reduction. Nonetheless trends computed over the historical period are weak and often contrasts with observations: this is particularly worrisome for summer Greenland blocking where models and observation significantly disagree. Finally, the intensity of global warming is related to blocking changes: wintertime European blocking is expected to decrease following larger global mean temperatures, while Western Russia summer blocking is expected to increase.
A mission proposal for understanding the origin of the lunar water: Scientific concept of the SELPHIE Mission
Authors: Futaana Yoshifumi , Barabash Stas ,   The SELPHIE mission proposal team
Published: March 2020

We are approaching a new era of space exploration: Utilization of our Moon for Human Beings. Intensive international efforts targeting human activities on the Moon have been initiated, and developed drastically in this decade. The revolution enabling the activities was the discovery of water at the Moon. We envisage utilizing the water for Lunar surface activities, as well as for explorations to farther Deep Space destinations.

Although multiple datasets have revealed the existence of Lunar water, fundamental scientific questions remain unanswered: Where has the surface and cold trap waters come from? What are the relative roles between solar wind protons and delivery from space for the Lunar surface water? What is the role of transportation of surface water to cold traps? This is the problem area that the SELPHIE (Surface, Exosphere, and Lunar Polar Hydration with Impact Experiments) mission is to reveal. The top-level science question of SELPHIE is "How is the lunar surface water delivered or produced, transported, and accumulated in cold traps?"

The baseline design of the SELPHIE mission is composed of six scientific sensors (three remote sensing and three in situ sensors) together with two impact experiments: An infrared spectrometer, visible camera, energetic neutral atom telescope, neutral mass spectrometer, solar wind monitor, and dust detector.  These sensors are operated from a 3-axis stabilized SELPHIE orbiter to reveal the comprehensive picture of the lunar water cycle. Two impact experiments (two identical systems, enabling two independent experiments) will be executed to reveal the source of water under cold traps. Each impact experiment contains a 6U cubesat and a small impactor (4 kg). The impactor will impact to a permanently shadowed crater to make ejecta. The cubesat will sound the plume by mass spectrometer and camera.

The norminal mission period is for 8-12 months, under the quasi-stationary polar orbit of the Moon (30-200 km altitudes). The pericenter is above the South Pole. The total mass of 600 kg (dry mass) with 61 kg payload mass is the baseline, while a further mass reduction could also be foreseen. The total cost, without payload developement, is within the ESA's F-class mission cost cap (150 MEuro).
A Hydrodynamics and Remote Sensing based Framework for Establishing Virtual Streamflow Measurement Stations in Scantily-gauged River Reaches
Authors: Sahoo Bhabagrahi , Sahoo Debi Prasad , Tiwari Manoj Kumar
Published: March 2020

Streamflow is the fundamental variable for any hydro-informatics based decision making to manage catchment-scale water resources. However, with the significant reduction in the number of streamflow gauging stations in many world-rivers, emphasis has now been shifted toward obtaining river discharges along the ungauged / scantily-gauged river reaches using innovative hydroinformatics tools. Many rivers which were gauged in the past, are now ungauged. In this context, this study considers a typical real-river, namely, the 48 km Bolani-Gomlai reach of the Brahmani River in eastern India, where a few historical concurrent streamflow hydrographs are available at the upstream and downstream gauging stations, which are defunct at present. Therefore, the main focus of this study is to generate spatially distributed high-frequent daily-scale river discharges along the selected ungauged river reach using the real-time optical remote sensing (RS) based imageries. To achieve this objective, the MIKE11 hydrodynamic (HD) model is setup and used in the selected reach to route the past streamflow records, available at the upstream section, so as to obtain the corresponding spatially distributed past discharges at 1 km resolution downstream. These routed historical streamflow records at each 1 km interval form the observed flow database for that specific RS-based virtual streamflow measurement station (VMS). For establishing the VMSs at each 1 km interval to estimate daily-scale river discharges, an RS-based methodology has been advocated that uses the spectral reflectances of the fused MODIS and Landsat satellite imageries and the MIKE11-HD derived corresponding routed past streamflows for calibration and validation. The different spectral behavior of land (C) and water (W) pixels in the near infrared of the electromagnetic spectrum is exploited by computing the (C/W) ratio of the fused imageries between two pixels located within (W) and outside (C), but close to the river. The values of C/W increase with the presence of water and, hence, with discharge. Moreover, in order to reduce the noise effect, an exponential smoothening filter is applied to obtain C/W*. Finally, the real-time filtered pixel ratios are used in the RS-based framework to estimate recent high-frequent streamflows in the ungauged river reach. The results reveal that the developed model has a very good potential which can be extended for high-frequent discharge estimation at any ungauged world-river reaches.
Automated location optimization of detention basins as a contribution to an efficient flood mitigation strategy
Authors: Teschemacher Sonja , Disse Markus
Published: March 2020

A considerable share of the losses by extreme flooding are in upstream areas, where centralized flood mitigation measures have no effect. Consequently, modern flood mitigation strategies address this problem by a distributed combination of measures, including nature-based solutions and decentralized flood detention basins. These small basins can be realized by minor changes in the landscape and can influence the runoff behavior at the site and downstream. However, the economic viability of the sites and the local and regional effectiveness depend on the location optimization, which is influenced by the local topography as well as by complex superposition effects.
We address this complexity with a combination of two innovative and automated optimization tools: LOCASIN (LOCation detection of retention and detention bASINs) is a flexible tool to automatically detect, characterize and evaluate detention basin locations. It is based on topographical data and provides information on the basin geometry as well as on the required curves for basin retention calculations. TOBAS (Tool for the Optimization of BASin efficiencies) calculates the effectiveness of a basin combination, taking into account the mutual influence when optimizing the throttle size. The input data includes the relation of water level and retention volume from LOCASIN and hydrographs generated by a hydrological model (e.g. WaSiM). Furthermore, TOBAS can be applied to select and dimension an optimized basin combination from the locations determined with LOCASIN. The optimization is based on the respective objective, e.g. effectiveness or economic efficiency. Hence, the joint application of both tools can contribute to improve efficient flood mitigation strategies and enhance flood resilience. The applicability of the tools and the benefits for the assessment of flood mitigation concepts were tested and confirmed by means of different Bavarian catchments.
Ion microprobe dating of fissure monazite in the Western Alps: insights from the Argentera Massif and Piemontais and Briançonnais Zones
Authors: Ricchi Emmanuelle , Gnos Edwin , Rubatto Daniela , Pettke Thomas
Published: March 2020

Ion probe 208Pb/232Th fissure monazite ages from high pressure regions of the Western Alps and from the Argentera Massif provide new insights on the tectonic evolution of the Western Alps during Cenozoic times. Fissure monazite is a hydrothermal mineral crystallizing during cooling/exhumation in Alpine fissures, an environment where monazite is highly susceptible to fluid-mediated dissolution-(re)crystallization. Fissure monazite ages directly record chemical disequilibrium occurring in a fissure environment, but growing evidences indicate that fissure monazite commonly register tectonic activity. Fissure monazite age domains from this study show that monazite crystallization occurred between ~32-30.5 Ma and ~31.5-30 Ma in the Piémontais and Briançonnais Zone of the High Pressure regions, and between ~17-15 Ma and in the north-eastern border of the Argentera Massif. So far, monazite ages were recorded between ~32-23 Ma and at ~20.5 Ma in the Briançonnais Zone and in the south-western border of the Argentera Massif respectively. Thus the presented dataset corroborate and complement already reported fissure monazite 208Pb/232Th ages from the Western Alps. This new fissure monazite ages compilation supports that Late Oligocene thrusting affected the High Pressure regions of the Western Alps, and that Early and Middle Miocene dextral strike-slips movements respectively affected the south-western and north-eastern margins of the Argentera Massif. Chemical observations provide new hints on fissure monazite growth conditions (e.g. leached host-rock minerals, oxidation conditions) encouraging to pursue chemical studies with a larger dataset on natural fissure monazite to better understand growth conditions under cleft environment.
EARLINET/ACTRIS Early Warning System for atmospheric aerosol aviation hazards
Authors: Papagiannopoulos Nikolaos , Amiridis Vassilis , Amodeo Aldo , Barsotti Sara , D'Amico Giuseppe , Gialitaki Anna , Kampouri Anna , Leto Giuseppe , Parks Michelle Maree , Scollo Simona , Solomos Stavros , Mona Lucia
Published: March 2020

Volcanic eruptions have the capacity to significantly impact human life, consequently, tools for mitigating them are of high importance. The early detection of a potentially hazardous volcanic eruption and the issuance of early warnings concerning volcanic hazards (e.g. ash dispersal), are key elements in the initiation of operational response procedures. Historically, lidars have not typically played a key operational role during volcanic eruptions, with other remote sensing instruments such as radars, infrared and ultraviolet cameras being preferred. Recently, a tailored product of the European Aerosol Research Lidar Network (EARLINET) for the early warning of the presence of volcanic ash and desert dust plumes at cruising altitudes has been developed. Here, we extend the applicability of this methodology to lidars and ceilometers near active volcanoes in Iceland and Mt. Etna in Italy. The tailored methodology and selected case studies will be presented, demonstrating its potential for real-time application during volcanic eruptions.

Acknowledgements: This work has been conducted within the framework of the E-shape (Grant Agreement n. 820852) and EUNADICS-AV (Grant agreement no. 723986) H2020 projects. Furthermore, the authors acknowledge the ACTRIS-2 and ACTRIS Preparatory Phase projects that have received funding from the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 654109) and from European Union’s Horizon 2020 Coordination and Support Action (grant agreement No. 739530), respectively.
Airborne Phased-Array Radar (APAR): The Next Generation of Airborne Polarimetric Doppler Weather Radar
Authors: Grubišić Vanda , Lee Wen-Chau , Lussier Louis L.
Published: March 2020

This paper presents a configuration of a novel, airborne phased array radar (APAR) motivated by major advances in cellular technology, component miniaturization, and radar antenna simulation software. This has paved the way for a next-generation radar being designed by NCAR/EOL to be installed on the NSF/NCAR C-130 aircraft. The APAR system will consist of four removable C-band active electronically scanned arrays (AESA) strategically placed on the fuselage of the aircraft. Each AESA measures approximately 1.5 x 1.5 m and is composed of 2368 active radiating elements arranged in a total of 37 line replaceable units (LRU). Each LRU is composed of 64 radiating elements that are the building block of the APAR system.

 

Polarimetric measurements are not available from current airborne tail Doppler radars. However, APAR, with dual-Doppler and dual polarization diversity at a lesser attenuating C-band wavelength, will further advance the understanding of the microphysical processes within a variety of precipitation systems. Such unprecedented observations, in conjunction with the advanced radar data assimilation schema, will be able to address the key science questions to improve understanding and predictability of significant weather.

A Mid-scale Research Infrastructure proposal is submitted to the National Science Foundation to request the implementation cost. The development is expected to take ~5 years after the funding is in place. It adopts a phased approach as an active risk assessment and mitigation strategy. At the present time, both the National Science Foundation and the National Oceanic and Atmospheric Administration are funding the APAR project for risk reduction activities. The APAR Team is actively seeking partners in industry and in the university community. An APAR science and engineering advisory panel has been organized.

 

The authors will review the overall design and current progress of APAR and outline ambitious future development work needed to bring this exceptional tool into full operation.
Evaluating Soil functions based on modeling under the impact of land use
Authors: Weller Ulrich , Lang Birgit , Mayer Stefanie , Stößel Bastian , Vogel Hans-Jörg , Wiesmeier Martin , Wollschläger Ute
Published: March 2020

While the change of soil functions under different management is important in the evaluation of long term strategies in agriculture, they are often difficult to be quantified. The obstacles are measurement problems on one hand, and on the other hand predictions for new management strategies and changing climate scenarios require estimates for yet unknown conditions. Comprehensive modeling of soil processes provides a road to both: Soil properties and processes that are per se difficult to measure can be included in a model to derive suitable indicators for soil unions. In this way, also, predicitons in the future for different climate scenarios and management strategies are possible.

In this presentation we give definitions for a limited set of indicators to quantify the most important soil functions in terms of both the current soil state and the soils’ potential to fulfill these functions. This includes the production of biomass, storage of carbon, storage and filtering of ground water, nutrient cycling, and habitat for biodiversity.

The quantitative evaluation of soil functions byel based indicators and their dynamics facilitates further socio-economic assessment and the development tools for governance.
Sediment trapping as a method for monitoring microplastic flux rates and deposition at aquatic environments
Authors: Saarni Saija , Hartikainen Samuel , Uurasjärvi Emilia , Meronen Senja , Hänninen Jari , Kalliokoski Maarit , Koistinen Arto
Published: March 2020

Microplastics are reported from wide range of aquatic environments with concentrations up to thousands of particles per kilogram of sediment. Due to a lack of temporal control, evaluation of the influx rate of microplastic pollution is not enabled. However, understanding the annual flux rate of microplastics to the aquatic environments is a crucial aspect for environmental monitoring and for risk assessment. A sediment trap method is widely applied in aquatic sedimentary studies in order to measure sedimentation rates and understand sedimentation processes. We have tested near-bottom sediment trap method in lacustrine and estuary environments, at central and coastal Finland, for measuring and quantifying the microplastic influx rate during one year. Near-bottom sediment traps with two collector tubes and known surface area, fixed one meter from the bottom, collect all particles that are about to accumulate on the basin floor of the water body. Controlled temporal interval of trap maintenance enables calculation and determination of local microplastic influx rate i.e. number of accumulating particles per time per surface area. The test results are very promising.  Near-bottom sediment traps can be used for long term monitoring in order to gain a deeper understanding of the microplastic transport and sedimentation processes, confirm and compare the feasibility and efficiency of different environmental conservation methods, setting threshold values for microplastic influx, and supervising that the defined target conditions are met.
The strength of the Earth Magnetic field around the Cretaceous Normal Superchron: new data from Costa Rica
Authors: Di Chiara Anita , Tauxe Lisa , Staudigel Hubert , Florindo Fabio , Yu Yongjae , Protti Quesada Marino , Hoernle Kaj
Published: March 2020

There has been an increasing effort toward the constraint of the average and long-term variability of the magnetic field strength, fundamental to better understand the characteristics and behaviour of the geomagnetic dipole field. Nonetheless, open questions remain about the value of the average dipole field, the relation between dipole strength and excursion reversal. Indeed, depending on the criteria adopted to analyse the current database, different long-term average values can be found, leading to different answers. The reason for the open debate can explained with the limited amount of data from key time intervals and geographical areas, due to both to complexities behind the method to obtain absolute paleointensities (several methods and experimental designs, selection criteria, high failure rate, etc..) and suitable materials.

Here, we focus on the Cretaceous Normal Superchron, a long period, from approximately 121 to 83 Ma, when the magnetic field was characterised by a stable polarity. Yet, few paleointensity data were available so far. In this study, we present new results from 48 Submarine Basaltic Glass sites from pillow lava margins, sampled on the upper crust sequence of the Costa Rica Ophiolite. Ar/Ar ages along with biostratigraphic age constraints from previous studies indicate ages ranging from from 139 to 94 Ma. After 473 samples were measured using the IZZI-Thellier protocol and analysed using strict selection criteria, 13 sites between 109 and 133 Ma gave reliable and robust results. Our new results from Costa Rica suggest that the strength of the Earth Magnetic field during CNS, 70.2 ± 21 ZAm2  are slightly lower than the pre-CNS and also lower than, for instance, at Troodos Ophiolite (81 ± 43 ZAm2; Tauxe and Staudigel 2004), consistent with the observations by Tauxe (2006) of an average dipole moment being substantially less than the present day value.
The Quest for the Gravity Wave Source
Authors: Geldenhuys Markus , Krisch Isabell , Preusse Peter , Ungermann Joern , Polichtchouk Inna , Krasouskas Lukas , Friedl-Vallon Felix , Riese Martin
Published: March 2020

Apart from orography, no specific sources of parametrized gravity waves are considered in most global circulation models. This is an inadequate generalization in the long run. In 2002, Charron and Manzini stated that no global gravity wave source climatology exist, and in the meantime, little has been done to address this observationally. A single observational case over Greenland is used to illustrate how difficult it is to disentangle the source of a gravity wave. The observation was made during the POLar STRAtosphere in a Changing Climate (POLSTRACC) campaign on 10 March 2016. The campaign was based in Kiruna, Sweden and investigated polar air during the polar vortex breakdown in spring. The gravity wave was observed between 10 and 15 km, with a horizontal wavelength of around 300 km and a vertical wavelength of around 2 km. Several plausible source mechanisms were present at the time of observation, a breaking Rossby wave, jet exit region, cold front, strong wind shear, and topography. POLSTRACC observations, ECMWF high resolution analysis and ERA 5 reanalysis were used to find the gravity wave source. Observations were obtained by the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) instrument based on the High Altitude Long Range (HALO) German research aircraft. GLORIA is an infrared spectrometer that measures many trace gasses in the mid-infrared frequencies. Radiance is changed by inverse-modelling to temperatures. The temperature structure of the gravity wave was tomographically reconstructed. The 3D observations correlate well with the model data. ERA 5 data and the Gravity-wave Regional Or Global Ray Tracer (GROGRAT) was used to determine the exact location of where the gravity wave was emitted. Evidence exists that the gravity wave could have been released by the geostrophic imbalance in the jet. In contrast, dedicated ECMWF model runs suggest that the origin of the gravity wave is in fact orography. However, the Scorer parameter suggests no gravity wave can propagate from the surface upwards. Two ECMWF model runs were used to prove this, one normal operational model run, and the second, with a ‘flat’ orography. This work indicates that care needs to be exercised to diagnose the source of gravity waves, especially without a full informational analysis. Our study illustrates that a better parametrization scheme of gravity wave sources should be included in models for a more realistic representation.
Marine plastic waste input between 1990-2015 and potential beaching scenarios
Authors: Laufkoetter Charlotte , Lang Kevin , Benedetti Fabio , Onink Victor , Vogt Meike
Published: March 2020

Marine plastic pollution has been recognized as a serious issue of global concern with substantial risks for marine ecosystems, fisheries, and food supply to people. Yet, the amount of plastic entering the ocean from land and rivers is barely understood. Currently, estimates exist for the coastal plastic input in the year 2010 on country-level resolution and for riverine plastic input for the year 2017. Key limitations are the restricted data availability on plastic waste production, waste collection and waste management. In addition, the transport of mismanaged plastic via wind and rivers is currently not well understood.

We present a model to estimate the global plastic input to the ocean for the years 1990-2015 on a 0.1x0.1° raster. To this end, we first train a machine learning model (random forests) and a linear mixed model to predict plastic waste production on country level, using data of municipal waste collection and several socio-economic predictor variables. We then estimate the amount of plastic waste that enters the environment, using high resolution population data and waste management data of each country. This is combined with distance-based probabilities of land and river transport to obtain the annual amount of plastic entering the ocean on a 0.1x0.1° spatial resolution. Our results indicate that global plastic waste production increased roughly linearly between 1990 to 2015. However, estimating the amount of mismanaged waste and the subsequent transport towards the ocean is afflicted with high uncertainties.

We then use the estimated plastic input into the ocean to force several Lagrangian model runs. These Lagrangian simulations include different parameterizations of plastic beaching, in particular they vary in terms of the beaching probabilities and the assumed residence time of plastic on beaches. We present the global distribution of beached plastic and the size of the reservoir of beached plastic in these model scenarios.
Volcanic sequences as reservoir rocks. Importance of natural fracture systems - a case study from the Faroe Islands area - North Atlantic Igneous Province (NAIP)
Authors: Eidesgaard Óluva R. , Boldreel Lars Ole , Schovsbo Niels H. , Ólavsdóttir Jana
Published: March 2020

Volcanic rocks have been known to be reservoirs for more than a century but due to their often complex geological settings, they are commonly avoided.

The North Atlantic Igneous Province (NAIP) is one of the largest igneous provinces in the world. Large ranges of rock types comprise the NAIP, including tholeiitic and alkali basalts, nepheline- and quartz-syenites, nephelinites and carbonatites. The province is Paleocene in age and covers large parts of the North Atlantic region today. Parts of the NAIP outcrop onshore the Faroe Islands, on the western and the eastern side of Greenland, on Iceland and on the British islands.

In the Faroe Islands region volcanic settings serve as shallow geothermal energy systems, shallow groundwater aquifers and hydrocarbon reservoirs. These settings have been studied by core data and wire-line logs and examples will be presented. The aim of this study is to examine the key important parameters governing the reservoir properties and occurrences.

In all settings microfractures are important as porosity and permeability enhancers and are often linked to lava emplacement pathways and specific lava types such as subaqueous hyaloclastites and pillow lavas.

Studies on water movement from onshore the Faroe Islands on the islands of Streymoy have shown that the water in the volcanic settings in the area is being transported through large fractures and weathered flow tops and bases. This has also been seen in e.g. similar large igneous volcanic provinces such as the Columbia River Basalt Group, USA, and the Deccan Traps, India. Six influx zones were identified in the three approximately 200 meter deep geothermal holes on Streymoy, the Faroe Islands. Three with visible macrofractures striking north-south dipping east, two through weathered units, while the sixth influx zone did not show any visible fractures or weathered zones (Eidesgaard et al., 2019).

Reference: Eidesgaard, Ó.R., Schovsbo, N.H., Boldreel, L.O. and Ólavsdóttir, J. 2019 Shalllow geothermal energy system in fractured basalt: a case study from Kollafjørður, Faroe Islands, NE-Atlantic Ocean. Geothermic vol. 82, p. 296-314.
Multi-hazard quantifications of the volcanic phenomena at La Soufrière volcano (Guadeloupe, Lesser Antilles)
Authors: Massaro Silvia , Sandri Laura , Selva Jacopo , Dioguardi Fabio , Bonadonna Costanza , Rossi Eduardo , Tamburello Giancarlo , Moretti Roberto , Komorowski Jean-Christophe , Moune Severine , Jessop David , Costa Antonio
Published: March 2020

In the last decade, probabilistic volcanic hazard assessment (PVHA) has become one of the most rapidly developing topics in volcanology. PVHA relies on a number of simulation tools, which have been catalogued within H2020 EUROVOLC project.

Here we apply two of these tools that will concur to a probabilistic multi-hazard assessment for volcanic phenomena at La Soufrière de Guadeloupe, as reported in reference scenarios elaborated by OVSG-IPGP and communicated to the authorities. In the last 9 kyr the activity at La Soufrière is characterized by recurrent effusive to explosive activity, sector collapses and intense fumarolic emissions. Based on literature data, we focus particularly on the most likely explosive (phreatic or hydrothermal) scenario and explore the hazard posed by gas dispersal and ballistics impact, which have never been the focus of PVHA. We also set up a preliminary spatial map for phreatic vent opening, a baseline for the PVHA here presented.
Crop growth and soil water fluxes at erosion-affected arable sites: A model inter-comparison based on weighing-lysimeter observations
Authors: Groh Jannis ,   crop-soil modelling initiative
Published: March 2020

Agro-ecosystem models have been developed to study effects of agricultural management on crop production, mostly from an agronomic point of view. Based on a biophysical process representation, their most prominent advantage is the coupled modelling of crop development and yield formation, as well as water and nutrients fluxes in the plant-soil system. Crop models have previously been calibrated based on experimental data with a focus on plant observations. Less attention has been given to soil water and solute dynamics despite the importance of plant nutrient availability and chemical leaching, particularly for arable soils often affected by erosion. The question was whether the description of soil processes and properties play an important role in the crop simulations.

The aim of this study was to compare the ability of agro-ecosystem models to predict crop development and water fluxes under changing environmental conditions. Observations on crop growth and soil water dynamics were obtained from four weighable lysimeter of the TERENO-SOILCan lysimeter network in the northeast of Germany (Dedelow). The intact soil monoliths are representative for the spatial soil variability of erosion-affected hummocky agricultural landscape. Twelve agro-ecosystem models (AgroC; DailyDayCent; Daisy; HERMES; MONICA; Theseus, Theseus-HydroGeoSphere; Theseus-Hydrus-1D; Expert-N coupled to CERES, GECROS, SPASS, and SUCROS) were tested. Crop development stages were used to calibrate the agro-ecosystem models. The model performance was tested against observed grain yield, aboveground biomass, leaf area index, actual evapotranspiration, drainage, and soil water content.

Model descriptions were highly diverse for both crop development and water fluxes. Crop growth and soil water fluxes were better predicted by the Multi Model Mean simulations than by any individual model. Results demonstrate that i) the hydraulic properties of erosion-affected soil profiles controlled the observed interactions between crop yield, plant development, and water fluxes, ii) data on phenological stages contained insufficient information content to calibrated agro-ecosystem models for soils affected by erosion, and iii) neither an individual model nor the Multi Model Mean could describe the observation on crop development and water dynamics, when using phenological stages only for model calibration. The results suggest that soil does matter in agro-ecosystem models and that weighable lysimeter can provide such soil related observation.
DORIS positioning from Sentinel-3A and Sentinel-3B data applying GPS onboard clock modeling
Authors: Stepanek Petr , Duan Bingbing , Hugentobler Urs , Filler Vratislav
Published: March 2020

A unique architecture of Sentinel-3A and Sentinel-3B satellites includes the shared ultra stable oscillator (USO) by DORIS and GPS receiver. This concept enables to apply GPS estimates of onboard clocks in DORIS processing and to substitute DORIS polynomial clock model by GPS epochwise model.  Such an approach is particularly profitable for the mitigation of South Atlantic Anomaly effect (SAA), affecting the short-term frequency stability of USO oscillator in South America and South Atlantic region.  GPS clock modeling precisely maps the SAA effect and enables us to demonstrate a difference between Sentinel-3A and Sentinel-3B USO sensitivity to SAA. Moreover, we present an impact on 3Dpositioning, where SAA-related bias reaches in extreme cases a decimeter level.  We also determine an effect of the precise clock modeling on the Earth rotation parameters estimation. Elimination of SAA effect also gives us an opportunity to get an SAA free DORIS solution of Sentinel-3A and Sentinel-3Bsatellites. Using this solution as a reference, we estimate an SAA effect on the DORIS positioning by satellites Jason-2, Jason-3, Sentinel, Cryosat-2 and Hy-2A and the efficiency of SAA mitigation strategies for these satellites. 
OSL rock surface exposure dating as a novel approach for reconstructing transport histories of coastal boulders over decadal to centennial timescales
Authors: Brill Dominik , May Simon Matthias , Mhammdi Nadia , King Georgina , Burow Christoph , Wolf Dennis , Zander Anja , Brückner Helmut
Published: March 2020

Wave transported boulders represent important records of storm and tsunami impact over geological timescales. Their use for hazard assessment requires chronological information that in many cases cannot be achieved by established dating approaches such as radiocarbon and U-Th dating. To fill this gap, we investigated the potential of optically stimulated luminescence rock surface exposure dating for estimating transport ages of coastal boulders. The approach was applied to wave-emplaced calcarenite clasts at the Rabat coast, Morocco. Calibration of the OSL surface exposure model was based on samples with rock surfaces exposed for ~2 years, and OSL exposure ages were evaluated against age control deduced from satellite images. The dating precision is very limited for all boulders due to the local source rock lithology, which contains low amounts of quartz and feldspar and was formed after MIS 5 (OSL signals are not in field saturation). Nevertheless, we propose a robust relative chronology for boulders that are not affected by significant post-depositional erosion and that share surface angle of inclination with the calibration samples. The relative chronology indicates that most boulders were moved by storm waves; these storms lifted boulders with masses of up to ~40 t; indicating that the role of storms for the formation of boulder deposits along the Rabat coast is much more significant than assumed previously. While OSL rock surface exposure dating cannot provide reliable absolute exposure ages for the coastal boulders from Rabat, the approach has great potential for boulder deposits composed of rocks with larger amounts of quartz or feldspar, older formation histories and lower susceptibility for erosion.
The Alpine Deep Structure from Surface Wave Tomography
Authors: Meier Thomas , El-Sharkawy Amr , Lebedev Sergei
Published: March 2020

Collisional tectonics of the Alps is driven by several slab segments. A detailed imaging of the lithosphere-asthenosphere system beneath the Alps is, however, challenging due to the relatively small size of the slab segments and the highly curved geometry of the Alps. Surface waves, due to their high sensitivity to variations in seismic velocities at lower crustal and upper mantle depth, are well suited to study the Alpine deep structure. New azimuthally anisotropic Rayleigh wave phase velocity maps are calculated from automated inter-station phase velocity measurements in a very broad period range (8 – 350 s). The constructed local dispersion curves are then inverted individually for 1-D shear-wave velocity models using a new implementation of the stochastic Particle Swarm Optimization (PSO) inversion algorithm that enables the calculation of a high-resolution 3-D shear-wave velocity model from the crust down to 300 km beneath the Alps. In the Central Alps, a nearly vertical high velocity anomaly down to depth of 250 km is imaged and interpreted as subducting Eurasian mantle lithosphere. In contrast, low velocities in the Western Alps at depth of approximately 100 km and downwards are supporting the shallow slab break-off model. In the Eastern Alps, the presence of a vertically continuous high-velocity anomaly from 75 km to about 200 km depth beneath the northern Eurasian foreland and the almost continuous extension of a high-velocity anomaly from the Dinarides towards the Eastern Alps hint at a bivergent slab geometry beneath the Eastern Alps caused by subducting mantle lithosphere of both Eurasian and Adriatic origin. There is also evidence for subduction of Adriatic lithosphere to the east beneath the Pannonian Basin and the Dinarides down to a depth of about 150 km. Beneath the northern Apennines, the model indicates an attached Adriatic slab, whereas a slab window is found beneath the central Apennines. The results show that surface wave tomography can contribute to the imaging of complex slab geometries and slab segmentation in the Alpine region.
IASI observations at the city scale
Authors: Safieddine Sarah , George Maya , Clerbaux Cathy , Paracho Ana , Boynard Anne , Hadji-Lazaro Juliette , Clarisse Lieven , Whitburn Simon , Coheur Pierre-Francois
Published: March 2020

IASI is a versatile mission, allowing the measurement of both meteorological parameters such as temperature and atmospheric composition for infrared absorbing species. With its long observation record and frequent overpasses, IASI is able to follow changes at different spatial scales. We studied IASI’s capability to track the anthropogenic signature associated with large cities, both in terms of temperature fingerprint (urban heat islands) and carbon monoxide (CO) content, a good tracer of human activity (transport, heating, and industrial activities). For this study we averaged the IASI data available since the launch of the first IASI, in order to increase the signal to noise, and allow discriminating the city from its surroundings. For skin temperatures we show that some cities experience much warmer temperatures than nearby rural areas, with day and night differences, whereas other urban areas appear as cold urban islands when surrounded by deserts Examples will be shown and compare with MODIS observations. For CO emitted by human activities, we identified some cities that stand out from their background, and were able to compare their CO associated signatures with measurements provided by other available spaceborne instruments such as Mopitt and TROPOMI.
Large-scale electron solar wind parameters of the inner heliosphere with Parker Solar Probe/FIELDS
Authors: Issautier Karine , Liu Mingzhe , Moncuquet Michel , Meyer-Vernet Nicole , Maksimovic Milan , Bale Stuart , Pulupa Marc
Published: March 2020

We present in situ properties of electron density and temperature in the inner heliosphere obtained during the three first solar encounters at 35 solar radii of the Parker Solar Probe mission. These preliminary results, recently shown by Moncuquet et al., ApJS, 2020, are obtained from the analysis of the plasma quasi-thermal noise (QTN) spectrum measured by the radio RFS/FIELDS instrument along the trajectories extending between 0.5 and 0.17 UA from the Sun, revealing different states of the emerging solar wind, five months apart. The temperature of the weakly collisional core population varies radially with a power law index of about -0.8, much slower than adiabatic, whereas the temperature of the supra-thermal population exhibits a much flatter radial variation, as expected from its nearly collisionless state. These measured temperatures are close to extrapolations towards the Sun of Helios measurements.

We also present a statistical study from these in situ electron solar wind parameters, deduced by QTN spectroscopy, and compare the data to other onboard measurements. In addition, we focus on the large-scale solar wind properties. In particular, from the invariance of the energy flux, a direct relation between the solar wind speed and its density can be deduced, as we have already obtained based on Wind continuous in situ measurements (Le Chat et al., Solar Phys., 2012). We study this anti-correlation during the three first solar encounters of PSP.
PGV-prediction for production blasts at the iron ore mine Mt. Erzberg, Austria
Authors: Tauchner Cornelia , Trabi Bernd , Bleibinhaus Florian
Published: March 2020

A seismic site characterization of the iron ore mine at Mt. Erzberg was performed in November 2016. The covered area measured about 4 km² within the active mine and the surrounding village. Within 4 weeks 125 3-component-geophones recorded 31 seismic events including production blasts. This data allowed for the computation of P and S velocity models. Which in turn were the basis for seismic wave field modelling with an elastic FD code. These simulations were used to calculate optimized blasting patterns for minimal vibrations at sensitive targets, like settlements and infrastructure, which were tested in a second and third experiment in June and October 19. (see contribution by Trabi et al.) 

In this study a statistical analysis of the resulting PPV-vector at any given geophone position was done, utilizing recorded blasts from 3 experiments. Using a scaled distance method, one can establish relationships between blast intensity, distance and ground vibrations. When compared to the PPV prognosis from the simulations, this analysis allows for assessments on prediction accuracy. General trends in PGV estimation can also be used to create site amplification factors to further enhance optimized blasting pattern calculations. 

This study is part of a large interdisciplinary EU funded project called SLIM, which focuses on sustainability in mining. 
Design storm estimation in Tuscany (Italy) through regional frequency analysis and generalized additive modelling
Authors: Pampaloni Matteo , Vannacci Virginia , Caporali Enrica , Bocci Chiara , Chiarello Valentina , Petrucci Alessandra
Published: March 2020

In the field of extreme hydrological events, design storm identification represents key element due to the links with flood risk as well as water resources availability and management.

In order to obtain a regional frequency analysis for studying and understanding the annual maximum of daily rainfall, two different statistic methods are proposed here on Tuscany Region (Central Italy). The first method concerns with the hierarchical approach on three levels: the studied area is divided into homogeneous regions and sub-regions, then the statistical homogeneity within the regions is verified through several homogeneity tests. Furthermore, the Two-Component Extreme Value (TCEV) probability distribution of the extreme rainfall is considered identical within each homogeneous region unless a scale factor, i.e. the index rainfall, estimated through a multivariate model based on climatic and geomorphological characteristics.

A Generalized Additive Model (GAM) for extremes is also implemented on the studied area assuming that the observations follow a Generalized Extreme Value - GEV distribution whose locations are spatially dependent. The research has been carried out starting from a general set of 922 rain gauges (Regional Hydrological Service of Tuscany – SIR), on time series of annual maximum of daily rainfall recorded from 1916 to 2017. The application of the two methods is discussed based on the comparison between the maps of the design storm for daily duration and 2, 20, 50, 100 e 200 years return periods.