bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating thermal losses and storage capacity in high-temperature aquifer thermal energy storage (HT-ATES) systems with well operating limits: insights from a study-case in the Greater Geneva Basin, Switzerland
Authors: Collignon Marine , Klemetsdal Øystein , Møyner Olav , Alcanié Marion , Rinaldi Antonio , Nilsen Halvor , Lupi Matteo
Published: March 2020

High temperature aquifer thermal energy storage (HT-ATES) can play a key role for a sustainable interplay between different energy sources and in the overall reduction of CO2emission. In this study, we numerically investigate the thermo-hydraulic processes of an HT-ATES in the Greater Geneva Basin (Switzerland). The main objective is to investigate how to handle the yearly excess of heat produced by a nearby waste-to-energy plant. We consider potential aquifers located in different stratigraphic units and design the model from available geological and geophysical data. Aquifer properties, flow conditions and well strategies are successively tested to evaluate their influence on the HT-ATES economic performance and environmental impact. This was achieved using a new open-access, user-friendly and efficient code that we also introduce here as a possible tool for geothermal applications.

 

The results highlight the importance of thorough numerical simulations based on more realistic exploitation when designing HT-ATES systems. We show that relations between thermal performance and the shape of the injected thermal volume are generally hard to derive when complex well schedules are imposed because the injected/produced volumes may not be equal. Despite more complex storage strategies to comply with legal regulations, the shallower group of investigated aquifers in this study remains economically more suitable for storage up to 90ºC. In average four well doublets will be required to store the yearly excess of energy. The deeper group of investigated aquifers, however, become interesting for storage at higher temperatures.
BITE, the Bayesian Ice Thickness Estimation model
Authors: Werder Mauro , Huss Matthias , Paul Frank , Dehecq Amaury , Farinotti Daniel
Published: March 2020

Accurate estimations of ice thickness and volume are indispensable for ice flow modelling, hydrological forecasts and sea-level rise projections. We present BITE, a new ice thickness estimation model based on a mass-conserving forward model and a Bayesian inversion scheme. The forward model calculates flux in an elevation-band flow-line model, and translates this into ice thickness and surface ice speed using a shallow ice formulation. Both ice thickness and speed are then extrapolated to the map plane. The model assimilates observations of ice thickness and speed using a Bayesian scheme implemented with a Markov chain Monte Carlo method, which calculates estimates of ice thickness and their error. We illustrate the model's capabilities by applying it to a mountain glacier, validate the model using 733 glaciers from four regions with ice thickness measurements, and demonstrate that the model can be used for large-scale studies by fitting it to over 30 000 glaciers from five regions. The results show that the model performs best when a few thickness observations are available; that the proposed scheme by which parameter-knowledge from a set of glaciers is transferred to others works but has room for improvements; and that the inferred regional ice volumes are consistent with recent estimates.
Short-term response of methane oxidation to biofertilizer treatments in sandy and clay soil.
Authors: Bieganowski Andrzej , Brzezińska Małgorzata , Polakowski Cezary , Duda Sylwia , Walkiewicz Anna , Tkaczyk Karolina , Jaromin-Gleń Katarzyna , Frąc Magdalena
Published: March 2020

The use of biofertilizers is a promising method of improving the quality of degraded and cultivated soils. High soil quality ensures high crop yields as well as is prerequisite to the proper soil functioning in the ecosystem. We tested methanotrophic activity of sandy and clayey soil (located in Poland - in Biszcza and Basznia, respectively) as affected by the use fertilizers with microorganisms and humic acids. Nine soil treatments were included (B: without microbial enrichments: (C) - Control zero without fertilization; (CF) - Control zero + fungal strains; (CB) - Control zero + bacterial strains; (UC) - Urea without microbiological amendment; (UA100) - Urea (100% + bacterial strains; (UA60) - Urea (60%) + bacterial strains; (NPK) - Control + NPK; (NPKF) - Control + NPK + fungal strains; and (NPKB) – Control + NPK + bacterial strains. Soil samples were collected two months after fertilization, and incubated in laboratory with methane (1% vol.) for 21 days. Soils differed in CH4 uptake rate and showed various response to the treatments. Generally, sandy soil showed higher methanotrophic activity than clayey soil. Fungal and bacterial strains (CF and CB) delayed CH4 oxidation in sandy soil, while not affected the process in the clay soil. Urea apparently inhibited CH4 oxidation in sandy soil without as well as with microbial enrichment (UC, UA100, UA60). In clayey soil urea had no effect. The use of NPK fertilizer without microbes inhibited CH4 consumption compared to Control (C) in sandy soil but not in clayey soil. Fungal (NPKF) and bacterial (NPKB) enrichments resulted in acceleration of the CH4 oxidation in sandy soil. In clayey soil fungal enrichments (NPKF) accelerated CH4 oxidation while bacterial amendments (NPKB) gave the opposite effect.

 

The presentation is financed by the National Centre for Research and Development under the program BIOSTRATEG3, contract number BIOSTRATEG3/347464/5/NCBR/2017 "BIO FERTIL"
A supervised technique for drill-core mineral mapping using Hyperspectral data
Authors: Contreras Cecilia , Khodadadzadeh Mahdi , Tusa Laura , Gloaguen Richard
Published: March 2020

Drilling is a key task in exploration campaigns to characterize mineral deposits at depth. Drillcores
are first logged in the field by a geologist and with regards to, e.g., mineral assemblages,
alteration patterns, and structural features. The core-logging information is then used to
locate and target the important ore accumulations and select representative samples that are
further analyzed by laboratory measurements (e.g., Scanning Electron Microscopy (SEM), Xray
diffraction (XRD), X-ray Fluorescence (XRF)). However, core-logging is a laborious task and
subject to the expertise of the geologist.
Hyperspectral imaging is a non-invasive and non-destructive technique that is increasingly
being used to support the geologist in the analysis of drill-core samples. Nonetheless, the
benefit and impact of using hyperspectral data depend on the applied methods. With this in
mind, machine learning techniques, which have been applied in different research fields,
provide useful tools for an advance and more automatic analysis of the data. Lately, machine
learning frameworks are also being implemented for mapping minerals in drill-core
hyperspectral data.
In this context, this work follows an approach to map minerals on drill-core hyperspectral data
using supervised machine learning techniques, in which SEM data, integrated with the mineral
liberation analysis (MLA) software, are used in training a classifier. More specifically, the highresolution
mineralogical data obtained by SEM-MLA analysis is resampled and co-registered
to the hyperspectral data to generate a training set. Due to the large difference in spatial
resolution between the SEM-MLA and hyperspectral images, a pre-labeling strategy is
required to link these two images at the hyperspectral data spatial resolution. In this study,
we use the SEM-MLA image to compute the abundances of minerals for each hyperspectral
pixel in the corresponding SEM-MLA region. We then use the abundances as features in a
clustering procedure to generate the training labels. In the final step, the generated training
set is fed into a supervised classification technique for the mineral mapping over a large area
of a drill-core. The experiments are carried out on a visible to near-infrared (VNIR) and shortwave
infrared (SWIR) hyperspectral data set and based on preliminary tests the mineral
mapping task improves significantly.
Atmospheric escape from rocky M-dwarf planets orbiting within the habitable zone
Authors: Dong Chuanfei
Published: March 2020

In the last two decades, the field of exoplanets has witnessed a tremendous creative surge. Research in exoplanets now encompasses a wide range of fields ranging from astrophysics to heliophysics and climate science. One of the primary objectives of studying exoplanets is to determine the criteria for habitability, and whether certain exoplanets meet these requirements. The classical definition of the Habitable Zone (HZ) is the region around a star where liquid water can exist on the planetary surface given sufficient atmospheric pressure. However, this definition largely ignores the impact of the stellar wind and stellar magnetic activity on the erosion of an exoplanet's atmosphere. Amongst the many factors that determine habitability, understanding the mechanisms of atmospheric loss is of paramount importance.

We will discuss the impact of exoplanetary space weather on the long-term climate evolution and habitability, which offers fresh insights concerning the habitability of exoplanets, especially those orbiting M-dwarfs, such as Proxima b and the TRAPPIST-1 planets. We will focus on a wide range of atmospheric compositions, ranging from exo-Venus candidates to Earth twins, as many factors remain unresolved at this stage. Future missions such as the James Webb Space Telescope (JWST) will play a crucial role in constraining the atmospheres of those exoplanets. For each of these cases, we will demonstrate the importance of the exoplanetary space weather on atmospheric ion loss and habitability.
Landslide physical vulnerability assessment using susceptibility map with hazard level-based rainfalls: a case study to Busan, Korea
Authors: Lee Ji-Sung , Ha Yong-Soo , Song Chang-Ho , Kang Hyo-Sub , Kim Yun-Tae
Published: March 2020

Most of landslide and debris flow take place during rainy season (June-September) in Korea. It is well known that rainfall is one of the most significant triggering factors in Korea. The mountainous area is composed of about 70%, which is a terrain where slope disaster can occur frequently. In addition, there is a great exposure to slope disaster due to rapid urbanization. The main objective of this paper is to assess landslide physical vulnerability using susceptibility map with hazard level-based rainfalls for urban area in Busan, Korea. Firstly, we computed rainfall thresholds for different hazard levels by using a quantile-regression method based on 258 landslide occurrence data from 1999 to 2019. Secondly, the combined landslide susceptibility map was developed according to hazard level-based rainfalls using both physical-based model and statistical-based model. To assess the vulnerability, source area were extracted from landslide high potential area based on the combined susceptibility map. The extracted source area is used to evaluate the propagation of debris flow. Affected building of debris flow was calculated using propagation results of debris flow. Physical vulnerability assessment was carried out using the affected building of debris flow from the analysis of the propagation of debris flow. Finally, vulnerability index (0 to 1) were categorized and evaluated by the degree of damage of the building. The proposed techniques can sufficiently contribute to protect of human causalities, property loss and also diminish the risk from landslides.
Variability of ecosystem scale water-use efficiency in a nutrient manipulation experiment
Authors: EI-Madany Tarek , Reichstein Markus , Carrara Arnaud , Martin M. Pilar , Moreno Gerardo , Gonzalez-Cascon Rosario , Penuelas Josep , Burchard-Levin Vicente , Hammer Tiana , Knauer Jürgen , Kolle Olaf , Luo Yunpeng , Pacheco-Labrador Javier , Perez-Priego Oscar , Rolo Victor , Wutzler Thomas , Migliavacca Mirco
Published: March 2020

Nitrogen (N) and phosphorus (P) are the two most important limiting soil nutrients reducing carbon sequestration globally. Through anthropogenic N-deposition, stoichiometric imbalances in plant-available N and P are expected in terrestrial ecosystems. This will result in increased P-limitation to plants and associated, but yet understudied, implications for ecosystem carbon sequestration, water-use efficiency (WUE), and biophysical properties. Here, we show results of a large-scale fertilization experiment designed to quantify effects of stoichiometric N:P ratio imbalances on WUE in a semi-arid tree-grass ecosystem. At the ecosystem-scale, the addition of N increased leaf area index, canopy chlorophyll content, and WUE. The addition of P, which relived the N:P imbalance, resulted in a further increase of WUE, more fixed carbon per transpired water. We conclude that increased N and combined N+P addition leads to shifts in many aspects of ecosystem functioning and biophysics, in particular related to water use strategies.
Evaluation of O3 forecasts of ALARO-CAMx and WRF-Chem
Authors: Flandorfer Claudia , Hirtl Marcus , Scherllin-Pirscher Barbara
Published: March 2020

ZAMG runs two models for air-quality forecasts operationally: ALARO-CAMx and WRF-Chem.

ALARO-CAMx is a combination of the meteorological model ALARO and the photochemical dispersion model CAMx and is operated at ZAMG since 2005. The emphasis of this modeling system is to predict ozone peaks in the north-eastern Austrian flatlands. The outer model grid covers Central Europe with a resolution of 13.8 km, the inner domain is centered over Austria with a resolution of 4.6 km. The model runs twice per day for a period of 48 hours.

The second operational air quality model at ZAMG is the on-line coupled model WRF-Chem. Meteorology is simulated simultaneously with the emission, turbulent mixing, transport, transformation as well as the fate of trace gases and aerosols. Two modeling domains are used for these simulations. The mother domain covers Europe with a resolution of 12 km. The inner, nested domain covers the Alpine region with a horizontal resolution of 4 km. The model runs two times per day for a period of 72 hours and is initialized with ECMWF forecasts.

The evaluation of both models is conducted for the period from January to September 2019 with the focus on ozone. The summer 2019 was the 2nd warmest summer since the beginning of the meteorological measurements in Austria more than 200 years ago. Although this summer had favorable conditions for Ozone production (sunny and hot weather, less rain), only a few air quality stations in Eastern Austria have measured exceedances of the ozone information threshold (180 µg/m³) on overall 5 days. The measurements of the air-quality stations are compared with the area forecasts for every province of Austria. Besides the evaluation, air quality forecasts of ALARO-CAMx and WRF-Chem are compared.
What is the optimal level of soil organic matter in tropical climates to prevent soil degradation?
Authors: Guzman Christian , Tebebu Tigist , Zimale Fasikaw , Steenhuis Tammo
Published: March 2020

Land degradation emerges when a critical component of productive land begins to diminish beyond a threshold. In tropical soils, organic matter may vary depending on the local climatic conditions and production of litter and organic materials and furthermore drastic changes in land use may be responsible for changes in organic matter which coincides with soil physical changes. In two research regions in mountainous (sub) humid conditions, organic matter was measured alongside surface and profile characteristics. In the Ethiopian Highlands, we measured organic matter, soil penetration resistance, soil texture, pH, and bulk density in three land use classifications (native forests, pasture lands, croplands).  In this region, soil in cropped regions and pasturelands had organic matter roughly below 4 %, had greater soil penetration resistance, lower pH (more acidic), and had greater bulk density. Soils in the native forests had organic matter roughly between the range of 4% to 12 % with lower soil penetration resistance, higher pH (less acidic) and lower bulk density.

The soils were investigated in the Andean region of the southwest of Colombia were analyzed for organic matter, hydraulic conductivity, soil texture, pH, and bulk density across two main land use classifications (native- and regenerated-forests and cultivated and pastureland). Soils in the cropped and pasturelands had organic matter around 4.8%, with low saturated hydraulic conductivity, greater fraction of fine particles, lower pH (more acidic), and greater bulk density. Soils in the native and regenerated forest cover had organic matter between 5 to 7%, with greater saturated hydraulic conductivity, lower fraction of fine particles, higher pH (less acidic), and a lower bulk density. While a universal optimal level of soil organic matter may not be applicable across various tropical regions, there are distinct changes that are consistent when organic matter falls below a regional threshold including increased compaction, acidity, and shifting of soil texture.  
Thermal stability of metalorganic compounds on volcanic olivine
Authors: Brau Joanna , Matzka Marco , Schmitt-Kopplin Philippe , Hertkorn Norbert , Ertel-Ingrisch Werner , Scheu Bettina , Dingwell Donald Bruce
Published: March 2020

Previously unknown class of metalorganic compounds revealed in meteorites [1] also found on the surfaces of silicate phases such as olivine, may have been involved in the emergence of life.  Here, the thermal stability of such organic compounds has been experimentally investigated under conditions which simulate those extant on the early Earth. We have studied olivines from the Hawaiian eruptions of 1959 and 2018. Individual mineral grains have been hand-picked to be free of secondary phases such as pyroxene or melt. We use a high temperature gas-tight tube furnace under CO-CO2 gas mixture at temperatures ranging from 950°C to 1350°C and oxygen fugacity ranging from 10-12 to 10-10 bar, within the stability field of olivine. The samples were contained in Pt crucibles and held for dwell times of 1 to 64 h. Quenching was performed by lifting the samples vertically out of the tube furnace. Using EPMA (electron microprobe analyzer) and RAMAN spectroscopy, we have mapped the state of the olivine samples. We observe that the composition of the individual mineral grains remains stable and homogeneous with thermal treatment. We are also investigating the role of impurities and cracks in the natural olivine and synthetic forsterite that might influence our study. The metalorganic cargo of these olivines has been analyzed using FT-ICR-MS (Fourier Transform ion cyclotron mass spectrometry). Preliminary results reveal systematic changes or organic molecular composition depending on time and heat of thermal treatment whose origins will be discussed.

[1] A. Ruf, B. Kanawati, N. Hertkorn, Q. Yin, F. Moritz, M. Harir, M. Lucio, B. Michalke, J. Wimpenny, S. Shilobreeva, B. Bronsky, V. Saraykin, Z. Gabelica, R. D. Gougeon, E. Quirico, S. Ralew, T. Jakubowski,  H. Haack, M. Gonsior, P. Jenniskens, N. W. Hinman, P. Schmitt-Kopplin. (2017) Previously unknown class of metalorganic compoundsrevealed in meteorites. PNAS 114 (2017) 2819-2824.
Erosional processes in the natural-anthropic geosystem of Vulcano Island (Italy)
Authors: Madonia Paolo , Di Maggio Cipriano
Published: March 2020

Vulcano, the southernmost island of the Aeolian Archipelago, has been characterized by an intense fumarolic activity since its last eruption from La Fossa cone (1888-1890). This island has a strong touristic vocation and frequentation, and here volcano-hydrothermal activity represents, at the same time, a landmark, one of the main causes of hydrogeological instability and a severe risk for human health. The space-time dynamic of this complex system is controlled by the mutual interactions among micro-meteorological, volcanic, tectonic, morphogenetic and anthropic processes.

La Fossa cone is affected by intense water erosion phenomena, also controlled by fumarolic activity as an obstacle for the growth of vegetation and a weathering factor. Man-made structures, with particular reference to deep modifications in the natural stream network induced by buildings and roads, exert a strong influence on these erosion processes, also fostered by episodic wildfires.

Another relevant theme is the acceleration of the coastal erosion processes in the Baia di levante area, driven by the circulation of chemically-aggressive hydrothermal fluids, which transforms the pristine volcanic minerals into phases like gypsum, anhydrite and clay minerals, significantly reducing the mechanical resistance of the rocks to the action of wave erosion. A general retreatment of the coastline (several meters in some locations) has been observed in the last twenty years, caused by the combined effect of volcanic activity, anthropic modifications and changes in sea level.
Helium in the Earth's foreshock: a global Vlasiator survey
Authors: Battarbee Markus , Blanco-Cano Xóchitl , Turc Lucile , Kajdic Primoz , Tarvus Vertti , Johlander Andreas , Alho Markku , Brito Thiago , Akhavan-Tafti Mojtaba , Dubart Maxime , Ganse Urs , Grandin Maxime , Karlsson Tomas , Pfau-Kempf Yann , Raptis Savvas , Suni Jonas , Palmroth Minna
Published: March 2020

The foreshock is a region of space in front of the Earth's bow shock, extending along the interplanetary magnetic field. It is permeated by ions and electrons reflected at the shock, low-frequency waves, and various plasma transients. The ion foreshock is dominated by a number of proton populations such as field-aligned beams, gyrating distributions and diffuse ions, as well as proton-excited waves. As the solar wind can contain a significant fraction of helium, it is of great interest to investigate how alpha-particles (He2+) are reflected into forming their own foreshock. We investigate the extent of the helium foreshock in relation to foreshock ultra-low frequency waves and protons using Vlasiator, a global hybrid-Vlasov simulation. We confirm a number of historical spacecraft observations at the foreshock regions associated with field-aligned beams, gyrating ion distributions, and specularly reflected particles, performing the first numerical global survey of the helium foreshock. We present wavelet analysis at multiple positions within the foreshock and evaluate the dynamics of gyrating ion populations in response to the transverse and compressive wave components. We also present Magnetosphere Multiscale (MMS) spacecraft crossings of the foreshock edge and compare Hot Plasma Composition Analyzer (HPCA) measurements of energetic ions with our simulation data, showing the variability of the foreshock edge suprathermal ion profiles.
Object‐oriented Soil Erosion Modelling and Daily Erosion Project: Laying the foundation for a new generation of soil erosion assessments in Europe
Authors: Borrelli Pasquale , Cruse Richard , Gelder Brian , Panagos Panos
Published: March 2020

Over the last two decades, geospatial technologies such as Geographic Information System and spatial interpolation methods have facilitated the development of increasingly accurate spatially explicit assessments of soil erosion. Despite these advances, current modelling approaches in Europe rest on (i) an insufficient definition of the proportion of arable land that is exploited for crop production, (ii) a neglect of the intra‐annual variability of soil cover conditions in arable land, and (iii) offer little understanding of the spatio-temporal trends of soil erosion. Here, we represent the recent developments of two methods tested to overcome current limitations and move towards the implementation of new modelling approaches in Europe.

The Object-oriented Soil Erosion Modelling and Monitoring v2.0 (O-SEMM) (Land degradation & development, 29, 1270-1281, 2018) combines highly accurate agricultural parcel information systems (LPIS) with crop statistics, Landsat 8 and Sentinel 2 satellite data and high temporal resolution rainfall data to assess soil erosion events at parcel level.

The Daily Erosion Project (DEP) (Earth Surface Processes and Landforms, 43, 1105-1117, 2018), developed by the Iowa State University, estimates soil erosion and water runoff occurring on hill slopes using the WEPP erosion prediction model.

References

Borrelli, P., Meusburger, K., Ballabio, C., Panagos, P., & Alewell, C. (2018). Object‐oriented soil erosion modelling: A possible paradigm shift from potential to actual risk assessments in agricultural environments. Land degradation & development, 29(4), 1270-1281.

Gelder, B., Sklenar, T., James, D., Herzmann, D., Cruse, R., Gesch, K., & Laflen, J. (2018). The Daily Erosion Project–daily estimates of water runoff, soil detachment, and erosion. Earth Surface Processes and Landforms, 43(5), 1105-1117.
Post-flight analysis of the aerosol impact on size distributions of warm clouds’ droplets, as determined in situ by cloud and aerosol spectrometers
Authors: Moacă Denisa Elena , Vâjâiac Sorin Nicolae , Calcan Andreea , Filip Valeriu
Published: March 2020

The influence of aerosol on the various aspects of the atmospheric properties as well as on the energetic balance is widely recognised in the scientific community and this issue is currently subject to worldwide intense investigations. Among the multiple ways aerosol particles are impacting the atmospheric environment, their interference with the phase transformations of the atmospheric water is of particular importance. Cloud microphysics, on the other hand, is one of the key components in weather forecast and, therefore, in pursuing daily domestic activities ranging from agriculture to energy harvesting and aviation. The micro-physical processes taking place in clouds are strongly influenced by the spatiotemporal variation of the size distribution of the cloud droplets. In this context, as in situ investigations of clouds seem appropriate, one of the most useful types of instruments is casted into the generic name of Cloud and Aerosol Spectrometer (CAS) that can be mounted on specialized research aircraft. The CAS working principle relies basically on measuring the forward scattering cross section (FWSCS) of light with a certain wavelength on a cloud particle and comparing it to the FWSCS computed for pure water spheres. The eventual matching of these values leads to assigning a certain value for the measured particle’s diameter. The light wavelength is usually chosen in a range where pure water has virtually no absorption. However, atmospheric aerosol frequently mixes up with cloud droplets (starting even from the nucleation processes) and alters their optical properties. By increasing absorption and/or refractivity with respect to those of pure water, one can easily show that the FWSCS-diameter diagram changes drastically by becoming smoother and with an overall significant decrease in absolute values. This means that a CAS will systematically count “contaminated” cloud droplets in a lower range of diameters, thus distorting their real size distribution. This effect is inherently degrading the objectivity of CAS measurements and should be more pronounced when levels of sub-micrometer sized aerosol increase at the cloud altitude. The present study aims at pointing out such correlation in order to estimate the reliability of size distributions (and of the ensuing cloud microphysical properties) obtained by CAS.
A warmer Mediterranean region at the Miocene to Pliocene transition
Authors: Vasiliev Iuliana , Boehn Daniela , Volkovskaja Darja , Schmitt Clemens , Agiadi Konstantina , Andreetto Federico , Mulch Andreas
Published: March 2020

Between 5.97-5.33 Ma several kilometre-thick evaporite units were deposited in the Mediterranean Basin during the Messinian Salinity Crisis (MSC). The MSC reflects a period featured by a negative hydrological budget, with a net evaporative loss of water exceeding precipitation and riverine runoff. The contemporary changes in continental and marine circum-Mediterranean temperature are, however, poorly constrained. Here we reconstruct continental mean annual temperatures (MAT) using branched glycerol dialkyl glycerol tetraether (GDGT) biomarkers for the time period corresponding to MSC Stage 3 (5.55-5.33 Ma). Additionally, for the same time interval, we estimate sea surface temperatures (SSTs) of the Mediterranean Sea using isoprenoidal GDGTs based TEX86 proxy. The excellently preserved organic biomarkers were extracted from outcrops and DSDP cores spread over a large part of the onland (Malaga, Sicily, Cyprus) and offshore (holes 124 and 134 from the Balearic abyssal plane and hole 374 from the Ionian Basin) Mediterranean Basin domain. The calculated MATs for the 5.55 to 5.33 Ma interval show values around 16 to 18 ºC for the Malaga, Sicily and Cyprus outcrops. The MAT values calculated for DSDP Leg 13 holes 124, 134 and Leg 42A hole 374 are lower, around 11 to 13 ºC.

For samples where the branched and isoprenoid tetraether (BIT) index was lower than the 0.4 we could calculate TEX86 derived SSTs averaging around 27 ºC for all sampled locations. Where available (i.e. Sicily), we compared the TEX86 derived SSTs with alkenone based, Uk37 derived SST estimates from the same samples. The TEX86 derived SST values are slightly higher than the Uk37 derived SST of 20 to 28 ºC. For the Mediterranean region, values between 19 and 27 ºC of the Uk37 derived SSTs were calculated for the interval between the 8.0 and 6.4 Ma (Tzanova et al., 2015), close to our calculations for Sicily section (20 to 28 ºC). Independent of common pitfalls that may arise in using molecular biomarkers as temperature proxies, both SST estimates independently hint towards much warmer Mediterranean Sea water during the latest phase (Stage 3) of the MSC. These elevated temperatures coincide with higher δD values measured on alkenones and long chain n-alkanes (both records indicating for more arid and/or warmer conditions than today between 5.55 and 5.33 Ma). We therefore conclude that the climate between 5.55 to 5.33 Ma was warmer than present-day conditions, recorded both in the Mediterranean Sea and the land surrounding it.
The dynamics of farmer migration and resettlement in the Dhidhessa River Basin, Ethiopia
Authors: Teweldebrihan Meseret , Pande Saket , McClain Michael
Published: March 2020

Extensive migration, settlement, and relocation of people for water resources development practice along a river basin often changes its hydrologic conditions and leads to conflicts for available water resources. In view of this, this study compiled the dynamics of population migration, settlement, and water resource developments in the Dhidhessa River Basin (DRB). The trend in migration time series for 1984-2017 based on census data indicates that the migrated rural population were ‘pulled’ by the government initiative. On the other hand, survey revealed that the farmer have dire reasons to migrate from their origin due to the scarcity of land and water. However, given the distance to a dam location, such potential migrants are financially incapable of relocating on their own. The study, therefore, calls for an analysis that takes into account the wellbeing of the displaced agrarian society at large of the migrant population in particular in the dam-affected area.
Development of a semi-distributed hydrological model on a tidal-affected river: application to the Adour catchment, France.
Authors: Mansanarez Valentin , Thirel Guillaume , Delaigue Olivier , Liquet Benoit
Published: March 2020

Streamflow estimation from rain events is a delicate exercise. Watersheds are complex natural systems and their response to rainfall events is influenced by many factors. Hydrological rainfall-runoff modelling is traditionally used to understand those factors by predicting discharges from precipitation data. These models are simplified conceptualisations and thus still struggle when facing some particular processes linked to the catchment. Among those processes, the tide influence on river discharges is rarely accounted for in hydrological modelling when estimating streamflow series at river mouth areas. Instead, estimated streamflow series are sometimes corrected by coefficients to account for the tide effect.

In this presentation, we explored a semi-distributed hydrological model by adapting it to account for tidal-influence in the river mouth area. This model uses observed spatio-temporal rainfall and potential evapotranspiration databases to predict streamflow at gauged and ungauged locations within the catchment. The hydrological model is calibrated using streamflow observations and priors on parameter values to calibrate each model parameters of each sub-catchments. A drift procedure in the calibration process is used to ensure continuity in parameter values between upstream and downstream successive sub-catchments.

This novel approach was applied to a tidal-affected catchment: the Adour’s catchment in southern France. Estimated results were compared to simulations without accounting for the tidal influence. Results from the new hydrological model were improved at tidal-affected locations of the catchment. They also show similar estimations in tidal-unaffected part of the catchment.
Love Wave Group Velocity Tomography of India, Himalaya and Tibet
Authors: Ghosh Monumoy , Mitra Supriyo
Published: March 2020

We present Love wave group velocity tomography calculated from broadband waveform data from Indian seismograph networks and global dataset downloaded from the IRIS-DMC. We first calculate path average 1-D fundamental mode Love wave group velocity between 10 s and 120 s period of the Transverse component of the seismograms. Then we combine these 1-D path average measurements using linear tomographic inversion, assuming great circular arc propagation, to compute 2-D group velocity map of the region at discrete periods. The region is adaptively parametrized to get high resolution at higher raypath density. We performed checker-board test to ascertain the resolution of the tomography maps and compute ray density map, raypath cross density map, and raypath orientation map to quantitatively analyze the controls of these parameters on the checker board resolution recovery. Tomographic maps at lower period show good correlation to the local geologic structures like low velocity in basins and high velocity in cratons and shields. At mid-period maps high velocity roots of cratons and low velocity in Tibet and Andaman- Burma subduction can be seen. At higher period low velocity in Tibet conforms with previous observations. We will do linear inversion of Love wave group velocity to get 3D SH wave velocity structure of the region.
What methods of interaction with users have proved to better perform for advanced co-development of climate services in the water sector?
Authors: Polo María José , Pimentel Rafael , Pérez-Palazón María José , Torralbo Pedro , Lorna Little , Menezes-Lomba Marilyn , Photiadou Christiana , Arheimer Berit
Published: March 2020

A wide offer of climate data sources/services is currently available dealing with future climate scenarios and projections. A huge effort has been done at European scale to promote and share openly this information. However, their use is not extensive and their potential is frequently underexploited. There is usually a significant gap between the complexity of climate metadata and the users’ capability of exploiting them. Furthermore, this gap is also found between the expertise of climate data providers and the every-day operation of the different potentially interested end-users. Additionally, in some sectors users are not aware of climate service capabilities which prevent them from valuing and then demanding such services.

In this context, co-development improves and fosters climate services’ usability and uptake when compared to a traditional one-side development approach, since it best meets users’ needs and demands. However, co-development can be time-consuming for both sides and less effective than expected if an adequate communication design is missing. In this context, what methods of interaction with users have proved to better perform for advanced co-development of climate services? And, what factors have best motivated users to interact? are key questions to provide guidelines and profit from the on-going initiatives.

Three different approaches with users (mainly in the water sector) were tested: guided online surveys (anonymous users); focus groups (users known to different partners in the project); case study clients (users regularly interact with project partners). Indicators and metrics were used to evaluate and value the contribution from each group in the context of co-development of climate services that give future projections of water availability. The results of this comparison provide a conceptual framework to design and apply co-development strategies for climate services oriented to different groups within the water sector.

This work was funded by the project AQUACLEW, which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Commission [Grant 690462].
Infrasound from the North Korea underground explosion and subsequent collapse on 3 September 2017
Authors: Che Il-Young , Kim Keehoon , Le Pichon Alexis
Published: March 2020

Strong ground motions induced by North Korea’s declared underground nuclear test in September 2017 and a subsequent subsurface collapse excited substantial and characteristic atmospheric acoustic waves (infrasound) that were detected by multiple stations at regional distances. Back-projection method is applied to the detected long-lasting coherent infrasound wavetrains related to the nuclear test. This allows to reconstruct source locations and reveals ground-to-air coupling in a large area over the northeast Korean Peninsula. To understand the excitation of atmospheric acoustic phases from the underground sources, full 3-D seismo-acoustic simulations are performed with pre-defined seismic moment tensor solutions of the underground sources. The simulations quantitatively predict the excitation of epicentral and diffracted acoustic phases developed by direct vertical ground motion at the immediate epicenter and by seismic surface waves propagating through high mountainous regions, respectively. In the atmosphere, the direct acoustic phases propagate spherically at the speed of sound, but the diffracted phases form inclined wavefronts in the atmosphere as the surface wave moves away from the epicenter. On a broad scale, the simulated acoustic coupling shows good agreement with the infrasound radiation patterns determined from the infrasound observations. Additional simulations for the subsequent subsurface collapse event show that an underground cavity collapse can be a potential mechanism for the production of low-frequency acoustic energy that is also detectable at regional distances. Finally, this study highlights the link between ground motions caused by underground sources and infrasound detection, further enabling infrasound as a depth discriminant for subsurface sources.
Effect of nitryl chloride chemistry on oxidants concentrations during the KORUS-AQ campaign
Authors: Kim Hyeonmmin , Park Rokjin , Jeong Jaein , Kim Saewung , Jeong Daun , Fu Xiao , Cho Seogju
Published: March 2020

Nitryl chloride (ClNO2) plays an important role as a night-time reservoir of NOX and the source of Cl radical during the daytime, which consequently affects the ozone photochemistry. Its impacts on regional air quality in East Asia, however, are not fully understood so far. We here use extensive observations during the international KORea-US cooperative Air Quality field study in Korea (KORUS-AQ), which occurred in May-June 2016, with a 3-D chemistry transport model to examine the impacts of ClNO2 chemistry on radical species and total nitrate concentrations in East Asia. We first update the model by implementing chlorine chemistry and latest anthropogenic chlorine emissions of China and South Korea. We conduct model simulations for May-June, 2016 and validate the model by comparing against the observations from the KORUS-AQ campaign. We find that the ClNO2 chemistry in the model results in an increase of ozone by ~1.4 ppbv (~2.5%), Cl radical by ~ 4.6x103 molec cm-3 (~3600%), OH ~8.2x104 molec cm-3 (~5.3%), HO2 ~6.6 molec cm-3 (~3.0%), a decrease of TNO3 (HNO3 + nitrate aerosol) concentrations by ~2 μg m-3 on a daily mean basis during the campaign. Overall, the enhanced conversion of NO to NO2 driven by ClNO2 chemistry contributes to higher oxidant concentrations in the model. As a result, the updated model shows a better agreement with the observations in Korea during the KORUS-AQ campaign.
Aircraft measurements of nitrous acid in excess of model predictions in the boundary layer and free troposphere
Authors: Schreiner Benjamin , Pfeilsticker Klaus , Kluge Flora , Rotermund Meike , Zahn Andreas , Ziereis Helmut , Bohn Birger , Schneider Johannes , Kaiser Katharina , Pozzer Andrea , Mertens Mariano
Published: March 2020

Middle and long-term  photo-chemical effects of local and regional pollution are not well quantified and are an area of active study. NOx (here defined as NO, NO2, and HONO) is a regional pollutant, which influences atmospheric oxidation capacity and ozone formation. Airborne measurements of atmospheric trace gases from the HALO (High Altitude Long Range) aircraft, particularly of NO, NO2, and HONO were performed as part of the EMeRGe (Effect of Megacities on the Transport and Transformation of Pollutants on the Regional to Global Scales) campaign over continental Europe and southeast Asia in July 2017 and April 2018, respectively. NO (and NOY), O3, and the photolysis frequencies of NO2 and HONO were measured in-situ. NO2 and HONO were inferred from Limb measurements of the mini-DOAS (Differential Optical Absorption Spectroscopy) instrument, using the novel scaling method (Hüneke et al., 2017). These measurements were compared with simulations of the MECO/EMAC models. In relatively polluted air-masses in the boundary layer and free troposphere, HONO measured in excess of model predictions (and previous measurements) suggests an in-situ formation and a significant source of OH as well as a pathway for re-noxification. Aerosol composition simultaneously measured  by the C-Tof-AMS instrument may reveal potential reaction mechanisms to explain the discrepancy. 
The magnetic signatures of oceanic tides in satellite data: A virtual-observatory approach
Authors: Velímský Jakub , Hammer Magnus D. , Finlay Christopher C.
Published: March 2020

The magnetic signatures of the M2, and more recently also the N2, and O1 oceanic tides have been successfully extracted from satellite observations (Grayver & Olsen, 2019). The traditional method uses the spatial representation of the tidal signals by spherical harmonics. Here we present an alternative approach based on the concept of virtual observatories, motivated by similar development in the analysis of the core field (Mandea & Olsen 2006). All quiet-time, night-side vector magnetic field values observed by the satellite(s) in the proximity of a selected virtual observatory are parameterized by a scalar magnetic potential represented by a cubic harmonic polynomial in a local Cartesian coordinate system. The time-dependence of the polynomial coefficients is constrained by selected tidal frequency, taking into account also the phase and amplitude corrections. The local approach offers several advantages over the use of the global spherical-harmonic base. The disturbances from external field in the polar areas have no impact on the inversion at lower latitudes, and local error estimates can be also provided. In this initial report, we will explore the possibilities of the new technique in terms of resolution, the combination of datasets from multiple satellites and the use of NS and EW field differences from the Swarm A-C pair.
Projecting the Reoccurrence of one in 100-year Caribbean Hurricanes under the Paris Agreement Goals
Authors: Vosper Emily , Lo Eunice , Mitchell Dann , Emanuel Kerry
Published: March 2020

Hurricanes are among the most destructive extreme weather events affecting humanity, in both social and economic terms. Hurricane Dorian (2019) caused widespread devastation when it stalled over the Bahamas as a category five hurricane bringing the most rainfall to the country from a hurricane in the reliable observation period, whilst secondary events such as flooding, landslides and disease left tens of thousands of people homeless. Climate change has been shown to influence hurricane activity, but so far there have been few studies that have explored hurricane response under the Paris Agreement goals especially in the case of stalling hurricanes. Here we show that extreme hurricane rainfall events, which affect the Caribbean region, are more likely in both of the Paris Agreement scenarios compared to the present climate with five of the six 100-year hurricanes studied occurring more often in these simulations. In particular, we show a currently one in 100-year rainfall event affecting the Bahamas is at least three times as likely under the Paris Agreement goals compared to the present climate.
Growth rate evaluation for the decay instability in space plasmas
Authors: Comisel Horia , Narita Yasuhito , Motschmann Uwe
Published: March 2020

Here we evaluate for the first time the growth rate of the decay instability in the 2-D wavevector domain spanning the parallel and perpendicular directions to the mean magnetic field. The growth rate is computed for the density perturbations based on the Hall MHD wave-wave coupling theory, which serves as a proxy for the energy spectrum of the compressive magnetic field fluctuations. The growth rate is then also determined for the daughter waves by considering the conservation of the frequencies and the wavevectors for the wave transmission (additive wave-wave coupling) and the wave reflection (subtractive wave-wave coupling). The visualized growth rate is helpful in evaluating the maximum propagation angle to which the decay instability (of the parallel propagating pump Alfven wave) operates.
Drivers of fog and low stratus - a satellite-based evaluation with machine learning
Authors: Pauli Eva , Andersen Hendrik , Bendix Jörg , Cermak Jan , Egli Sebastian
Published: March 2020

In this study the distribution of fog and low stratus (FLS) relative to land cover and meteorological conditions in continental Europe is investigated using a state-of-the-art machine learning technique  and geostationary satellite data. While analyses of the spatial and temporal patterns of FLS exist, the relationships to land cover and meteorological conditions have not been studied explicitly, quantitatively and on a continental scale.
The machine learning model is built using daily means of a FLS dataset from Egli et al. (2017) as the predictand, and different land surface and meteorological parameters as predictors over continental Europe from 2006-2015. The application of a machine learning approach provides the ability to explicitly, synchronously and quantitatively link suspected determinants of FLS to its occurrence.
The model shows good performance with R² values ranging between 0.5 and 0.9, depending on model grid size, season and further settings such as the exclusion of low pressure values and subtraction of seasonality. It is thus able to adequately represent the dynamics that drive FLS development. Based on a systematic analysis of this model, the most important features for FLS prediction are mean surface pressure, wind speed, and FLS on the previous day. High mean surface pressure, high FLS cover on the previous day, low evapotranspiration, wind speed and land surface temperature lead to higher predicted FLS values.
Generally the results show that it is possible to predict FLS occurrence over continental Europe using meteorological as well as land surface parameters with good performance indicating the benefits of using machine learning in the analysis of non-linear, multivariate systems such as the land-atmosphere system. Further studies will integrate the machine learning model into a land surface based model grid and implement fog and low cloud properties as predictands.