bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of sediment in the marine C cycle—insights from a coupled ocean-sediment model
Authors: Völker Christoph , Ye Ying , Butzin Martin , Köhler Peter , Munhoven Guy
Published: March 2020

Fluxes of particles and solutes between deep ocean and marine sediment are essential in the biogeochemical cycles of carbon and nutrients, such as nitrogen, silicon and iron. On a millennial time scale, sediment accumulation connects the ocean with the surface lithosphere which impacts the climate through weathering. Despite the importance of sediments in the climate system, fluxes between ocean and sediment are poorly constrained and most of the ocean models use very simplified parameterisation based on some measurements on shelves.

Here we like to present the coupling of the marine biogeochemical model REcoM2 (Regional Ecosystem Model, version2) coupled with the sediment model MEDUSA (Model of Early Diagenesis in the Upper Sediment with Adaptable complexity) for a better understanding of the role of sediments in the marine carbon cycle. MEDUSA resolves chemical reactions and physical processes within the marine sediments. As REcoM allows deviations from the Redfield C:N ratio both in phytoplankton production and remineralisation, the molar ratio of carbon and nitrogen in sinking fluxes vary with time and depth. Our MEDUSA set-up is made to be able to deal with flexible stoichiometry in sinking fluxes by resolving two classes of organic matter with different C:N ratios and degradation rates. We performed model-data comparisons of calcite, opal and particulate organic matter in sediment for present-day to constrain the biological productivity and sinking behaviour of particles in water column, and studied the role of the marine carbon cycle for glacial carbon storage and the drawdown of atmospheric CO2 in simulations under glacial climate conditions. 
Warmer climate projections in CMIP6: the role of changes in the greenhouse gas concentrations from CMIP5 to CMIP6
Authors: Wyser Klaus , Kjellström Erik , Koenigk Torben , Martins Helena , Döscher Ralf
Published: March 2020

Many modelling groups have contributed with CMIP6 scenario experiments to the CMIP6 archive. The analysis of CMIP6 future projections has started and first results indicate that CMIP6 projections are warmer than their counterparts from CMIP5. To some extent this is explained with the higher climate sensitivity of many of the new generation of climate models. However, not only have models been updated since CMIP5 but also the forcings have changed from RCPs to SSPs. The new SSPs have been designed to have the same instantaneous radiative forcing at the end of the 21st century. However, we find that in the EC-Earth3 model the effective radiative forcing differs substantially when the GHG concentrations from the SSP are replaced by those from the corresponding RCP with the same nameplate RF. We estimate that for the SSP5-8.5 and SSP2-4.5 scenarios 50% or more of the stronger warming in CMIP6 than CMIP5 for the EC-Earth model can be explained by changes in GHG gas concentrations. Other changes in the forcing datasets such as aerosols only play a minor role for the additional warming. The discrepancy between RCP and SSP forcing datasets needs to be accounted for when comparing CMIP5 and CMIP6 climate projections and should be properly conveyed to the climate impact, adaptation and mitigation communities.
Identification of droughts from monitored and modelled vegetation condition for improved water management in semi-arid areas
Authors: Bayer Anita , Mihalyfi-Dean Christine , Behling Robert , Lorenz Christof , Foerster Saskia , Roessner Sigrid , Arneth Almut
Published: March 2020

Semi-arid areas suffer from small amounts and a large variability in rainfall combined with an increasing risk of droughts under climate change. These long and short-term changes in water availability directly affecting regional livelihoods are depicted in the condition of the rather sparse vegetation. In this study, seasonal and long-term trends in indicators of the vegetation condition related to water availability and droughts (NDVI vs. fAPAR, NPP, soil water content, excess water) are identified from remote sensing data (MODIS) and a process-based dynamic vegetation model (LPJ-GUESS) for at least two semi-arid river basins. Identified trends of both methods are compared and evaluated based on the underlying processes and related to knowledge of past drought events. Finally, we answer the question, which methods and indicators are suitable to identify changes in the vegetation condition preceding a drought and during drought phases considering the methods and indicators as above plus simple precipitation-based drought indicators (e.g. standardized precipitation index, SPI) and enhanced drought indicators applying multiple indicators theirselves (e.g. combined drought indicator, CDI). The study is imbedded in the SaWaM project (Seasonal Water Management for semi-arid areas) and contributes to improved water management in the project regions by the integrated analysis of remote sensing and ecosystem modelling results that are made available to regional stakeholders tasked with water management in an online tool .
The overwhelming jungle of climate information and the role of climate services.
Authors: Buontempo Carlo
Published: March 2020

Climate adaptation often requires high resolution information about the expected changes in the statistical distribution of user-relevant variables. Thanks to targeted national programmes, research projects and international climate service initiatives  this kind of information is not only becoming more easily available but it is also making its way into building codes, engineering standards as well as the risk assessments for financial products.  If such an increase in the use of climate data can be seen as a positive step towards the construction of a climate resilient society, it is also true that the inconsistencies that exist between the information derived from different sources of information, have the potential to reduce the user uptake, increase the costs of adaptation and even undermine the credibility of both climate services and the underpinning climate science.

This paper offers a personal reflection on the emerging user requirements in this field. The presenation also aims at suggesting  some prelimimary ideas in support of the development of appropriate methodologies for extracting robust evidence from different sources in a scalable way.
How syn-rift sedimentation promotes the formation of hyper-extended margins
Authors: Buiter Susanne
Published: March 2020

Seismic observations show that some rifted continental margins may have substantial amounts of offshore sediments. For example, sediment layers of several kilometres thick are found on the margins of Mid Norway, Namibia and Angola. Intriguingly, these margins are wide, being characterised by distances of several hundreds of kilometres from typical continental crustal thicknesses of 30-40 km to clearly identifiable oceanic crust. On the other hand, some margins that are sediment-starved, such as Goban Spur, Flemish Cap and Northern Norway, have short onshore-to-offshore transitions. Variations in the amount of sediments not only impact the development of offshore sedimentary basins, but the changes in mass balance by erosion and sedimentation can also interact with extensional tectonic processes. In convergent settings, such feedback relationships between erosion and tectonic deformation have long been highlighted: Erosion reduces the elevation and width of mountain belts and in turn tectonic activity and exhumation are focused at regions of enhanced erosion. But what is the role played by surface processes during formation of rifted continental margins?

I use geodynamic finite-element experiments to explore the response of continental rifts to erosion and sedimentation from initial rifting to continental break-up. The experiments predict that rifted margins with thick syn-rift sedimentary packages are more likely to form hyper-extended crust and require more stretching to achieve continental break-up than sediment-starved margins. These findings imply that surface processes can control the style of continental break-up and that the role of sedimentation in rifted margin evolution goes far beyond the simple exertion of a passive weight.
Climatic Drivers of Greening Trends in the Alps
Authors: Cremonese Edoardo , Filippa Gianluca , Galvagno Marta , Morra di Cella Umberto , Migliavacca Mirco
Published: March 2020

Since the 1980s, vegetated lands have experienced widespread greening at the global scale. Spatial patterns and mechanisms of this phenomenon were extensively investigated, especially in the Arctic and sub-Arctic regions. Greening trends in the European Alps have received less attention, although this region has experienced strong climate and land-use changes during recent decades. We investigated the rates and spatial patterns of greening in an inner-alpine region of the Western Alps. We used MODIS-derived normalized difference vegetation index (NDVI) at 8-day temporal and 250 m spatial resolution, for the period 2000–2018, and removed areas with disturbances in order to consider the trends of undisturbed vegetation. We had two objectives :

(i) quantify trends of greening in a representative area of the Western Alps; and (ii) examine mechanisms and causes of spatial patterns of greening across different plant types.

Sixty-three percent of vegetated areas experienced significant trends during the 2000–2018 period, of which only 8% were negative. We identify (i) a climatic control on spring and autumn phenology with contrasting effects depending on plant type and elevation, and (ii) land-use change dynamics, such as shrub encroachment on abandoned pastures and colonization of new surfaces at high elevation.

Below 1500 m, warming temperatures promote incremental greening in the transition from spring to summer, but not in fall, suggesting either photoperiod or water limitation. In the alpine and sub-alpine belts ( > 1800 m asl), snow prevents vegetation development until late spring, despite favorable temperatures. Instead, at high elevation greening acts both in summer and autumn. However, photoperiod limitation likely prevents forested ecosystems from fully exploiting warmer autumn conditions. We furthermore illustrate two emblematic cases of prominent greening: recent colonization of previously glaciated/non vegetated areas, as well as shrub/tree encroachment due to the abandonment of agricultural practices. Our results demonstrate the interplay of climate and land-use change in controlling greening dynamics in the Western Alps.
Modelling the surface mass balance of the Greenland Ice Sheet from 6000 BP to the year 2200
Authors: Krebs-Kanzow Uta , Xu Shan , Yang Hu , Gierz Paul , Lohmann Gerrit
Published: March 2020

The surface mass balance scheme dEBM (diurnal Energy Balance Model) provides a novel interface between atmosphere and land ice for Earth System modelling, which is based on the energy balance of glaciated surfaces. In contrast to empirical schemes, dEBM accounts for changes in the Earth’s orbit and atmospheric composition. The scheme only requires monthly atmospheric forcing (precipitation, temperature, shortwave and longwave radiation and cloud cover) and is computationally inexpensive, which makes it particularly suitable to investigate the response of ice sheets to long term climate change.
Here, we analyze the surface mass balance of the Greenland Ice Sheet (GrIS)  based on a climate simulation which covers the last 6000 years and a climate projection which extends to the year 2200. We validate our results with recent surface mass balance estimates from observations and regional modelling. Our model results allow to compare two distinctly different warm periods: the Mid Holocene (approx. 6000 years before present), which is characterized by intensified summer insolation, and the next centuries,  which will be characterized by reduced outgoing long wave radiation. We also investigate whether the temperature - melt relationship, as used in empirical  schemes, remains stable under changing insolation and atmospheric composition.

Krebs-Kanzow, U., Gierz, P., & Lohmann, G. (2018). Brief communication: An ice surface melt scheme including the diurnal cycle of solar radiation. The Cryosphere, 12(12), 3923-3930.
Electrical resistivity variation connected to volcanic earthquake in the Campi Flegrei, Italy
Authors: tarallo daniela , Cavuoto Giuseppe , Di Fiore Vincenzo , Pelosi Nicola , Punzo Michele , Milano Maurizio , Contiero Massimo , Iavarone Michele , Iorio Marina
Published: March 2020

In this study we show an 2D Electrical Resistivity Tomography (ERT) survey acquired in Agnano site pre (Dec 5th, 2019) and post (Dec 12th, 2019) earthquake events occurred in Pisciarelli-Solfatara areas. This earthquake swarm consisted of sequence of 34 earthquakes with Magnitude (Md) -1.1≤Md≤2.8 at depths between 0.9 and 2.3 km. In particular, the earthquake of Dec 06th, 2019 at 00:17 UTC with Md = 2.8 (depth 2 km) was the maximum recorded event since bradyseismic crisis began in 2005.

The ERT survey allow us to identify the main structural boundaries (and their associated fluid circulations) defining the shallow architecture of the Agnano volcano. The hydrothermal system is identified by very low values of the electrical resistivity (<20 Ω m). Its downwards extension is clearly limited by the lava and pyroclastic fragments, which are relatively resistive (>100 Ω m). The resistivity values are increased after the main shock. This increase in resistivity may have been caused by a change in the state of stress and a decrease in pore pressure (subsequent depressurization). Previously to the earthquake, an increase in pressurized fluids has been observed which have reduced the resistivity values. The present observation suggests that the temporal variation of the resistivity values is related to the variation of the pore fluid pressure in the source area of the swarm, facilitated by earthquake and the subsequent fluid diffusion. The combination of these qualitative results with structural analysis leads to a synthetic model of magmatic and hydrothermal fluids circulation inside the Agnano area, which may be useful for the assessment of potential hazards associated with a renewal of fluid pressurization, and a possibly associated partial flank-failure.
A Sentinel-1 based European crop parcel map using 2018 in-situ LUCAS Copernicus observations
Authors: Astrid Verhegghen , Raphaël d'Andrimont , Guido Lemoine , Peter Strobl , Marijn van der Velde
Published: March 2020

Efficient near-real time and wall-to-wall land monitoring is now possible with unprecedented detail because of the fleet of Copernicus Sentinel satellites. This remote sensing paradigm is the consequence of the freely accessible, global, Copernicus data, combined with affordable cloud computing. However, to translate this capacity in accurate products, and to truly benefit from the high spatial detail (~10m) and temporal resolution (~5 days in constellation) of the Sentinels 1 and 2, high quality and timely in-situ data remains crucial. Robust operational monitoring systems are in need of both training and validation data. 

Here, we demonstrate the potential of Sentinel 1 observations and complementary high-quality in-situ data to generate a crop type map at continental scale. In 2018, the Land Cover and Land Use Area frame Survey (LUCAS) carried out in the European Union contained a specific Copernicus module corresponding to 93.091 polygons surveyed in-situ. In contrast to the usual LUCAS point observation, the Copernicus protocol provides data on the extent of homogeneous land cover for a maximum size of 100 x 100 m, making it meaningful for remote sensing applications. After filtering the polygons to retrieve only high quality sample, a sample was selected to explore the accuracy of crop type maps at different moments of the 2018 growing season over Europe. The time series of 10 days VV and VH were classified using Random Forest models. The crops that were mapped correspond to the 13 major crops in Europe and are those that are monitored and forecast by the JRC MARS activities (soft wheat, maize, rapeseed, barley, potatoes, ...). Overall, reasonable accuracies were obtained (~80%). Although no a priori parcel delineation was used, it was encouraging to observe the relative homogeneity of pixel classification results within the same parcel. In the context of forecasting, we specifically assessed at what time in the growing season accuracies moved beyond a set threshold for the different crops. This ranged from May for winter crops such as soft wheat, and September for summer crops such as maize. 

Our results contribute to the discussion regarding the usefulness, benefits, as well as weaknesses, of the newly acquired LUCAS Copernicus data. Doing so, this study demonstrates the potential of in-situ surveys such as LUCAS Copernicus module  specifically targeted for Earth Observation applications. Future improvements to the LUCAS Copernicus survey methodology are suggested. Importantly, now that LUCAS has been postponed to 2022, and aligned with the Copernicus space program, we advocate for a European Union wide systematic and representative in-situ sample campaign relevant for Earth Observation applications, beyond the traditional LUCAS survey. 
Radiation Characteristics of Seismic Source Arrays
Authors: Trabi Bernd , Tauchner Cornelia , Bleibinhaus Florian
Published: March 2020

Blasting operations in quarries are accompanied by ground vibrations which can endanger buildings nearby. A production blast is made of several holes with a small distance to each other, which are blasted with a time delay, to reduce the ground vibrations. These production blasts produce a specific radiation pattern. It would be favorable to focus the ground vibrations to a less dangerous direction or area. To optimize the radiation pattern of seismic waves the blast configuration can be modified. For the optimization an analytic solution, based on Fourier shift theorem can be used. This assumes a model with a homogeneous half space and similar source wavelets for low frequencies. Because we want to predict the ground vibrations for a more realistic inhomogeneous case, a numerical forward modeling on a 3D model of mount Erzberg was performed with a 3D elastic code with topography. The 3D model of mount Erzberg is the result of a tomographic travel time inversion. One problem is that the spectral response of a single blast is unknown and therefore we had to find a transfer function which transfers the numeric spectral response to the observed spectral response. After applying the transfer function the amplitude spectra of the numeric solution show a good match to the amplitude spectra of the observed production blasts. The main goal is to reduce the ground vibrations at sensitive areas. This is achieved by blasting simultaneously two blast arrays with a greater distance to each other with optimized time delays. To optimize the time delays we developed a global search algorithm, based on Marcov chain Monte Carlo method which finds potential blast configurations, with minimum impact to critical locations nearby the quarry. These blast configurations serve as proposal for real production blasts at mount Erzberg. This study is part of the EU-funded project SLIM (Sustainable Low Impact Mining, www.slim-project.eu).
Modeling the impacts of cave ventilation and CO2 dynamics on speleogenesis
Authors: Covington Matthew , Gabrovšek Franci
Published: March 2020

Approximately 10 years worth of field observations of dissolved and gaseous CO2 within caves and karst springs across a variety of settings suggest that CO2 dynamics provide a first-order control on both the spatial and temporal variability in dissolution rates within karst systems. Three primary effects emerge from the field studies: 1) Changes in stream slope, sediment characteristics, and resulting CO2 production and exchange can drive longitudinal variability in dissolution rates along cave streams; 2) Cave airflow patterns, and resulting cave gaseous CO2 concentrations, can be the primary control on the variability of in-stream dissolution rates over storm to seasonal timescales; 3) The maturation of karst systems and resulting increases of permeability within the vadose zone can increase ventilation of the subsurface, reduce the PCO2 of water flowing through cave passages, and ultimately reduce dissolution rates within these passages. While these effects are evident from the field data, it is difficult to quantify the long-term impacts of these effects on the evolution of karst systems using field data alone. The processes of CO2 production, cave ventilation, and CO2 exchange between gas and liquid phases have not been included in previous numerical models of speleogenesis. Here we extend existing models of speleogenesis to incorporate a suite of processes that are relevant for simulating physically realistic CO2 dynamics. We use this new model to explore the impacts of ventilation and CO2 exchange over timescales relevant for the evolution of karst aquifers. 

 
The water-food-energy-land nexus: Hotspots and scenario-dependency of competition for water between energy, food and nature
Authors: de Vos Lotte , Biemans Hester , Doelman Jonathan , Stehfest Elke
Published: March 2020

Freshwater is a shared resource needed both for food and energy production, and to sustain  ecosystems worldwide. Freshwater ecosystems are already experiencing biodiversity declines that are higher than in most terrestrial systems. With climate change and an expected increase in global population and income, the trade-offs between societal demand and nature become even more stringent. Insight in how these developments might impact future water use helps to identify strategies to ensure a healthy environment while still meeting global water demands. 

This study evaluates competition for water within the food-water-energy nexus, while explicitly accounting for the amount of water required by nature. It does so by implementation of Environmental Flow Requirements (EFRs), which are in this case defined as the quantity and timing  of  water  flows  required  to  sustain  freshwater  and  estuarine ecosystems. Simulations are performed with the integrated assessment model framework IMAGE, which includes the global vegetation and hydrology model LPJmL.  This framework combines regional agro-economic, energy and climate policy modelling with land-use, dynamic vegetation and hydrological modelling. 

Different pathways of socio-economic developments (Shared Socio-economic Pathways (SSPs)) are evaluated up until the year 2100, including a climate change mitigation scenario aiming for the long-term mitigation target of 2 °C. Earlier studies for SSP-1, SSP-2 and SSP-3 have already shown that while global water withdrawals are expected to increase for all cases, the demands for SSP-3 are generally higher than the demands for SSP-1. This study adds to this by showing how water demands affect environmental flows, or vice versa. The results present an overview of hotspots where future water demand for food, energy and nature might still compete, and where the effects are ameliorated if the world will develop towards a more sustainable path. Additionally, the results present how irrigation efficiency improvements and climate change mitigation measures can help alleviate the pressure in the food-water-energy nexus, although the latter depends on the choice of mitigation pathway. 
Far-ultraviolet Ionospheric Photometer
Authors: Peng Ruyi , Fu Liping
Published: March 2020

As a space-based optical remote sensing method, Far-ultraviolet Ionospheric Photometer with small size, low power consumption, high sensitivity is an important means to detect physical parameters of the ionosphere. Using the Far-ultraviolet Ionospheric Photometer to detect the intensity of ionospheric 135.6nm night airglow can obtain the ionospheric TEC, F2 layer peak electronic density(NmF2), which can be used to study the information on changes in ionospheric space environment,and the impact of the ionosphere on the radio communications, etc.; The ionospheric 135.6nm day airglow and the LBH radiation radiance can be used to obtain the ionospheric O / N2 ratio information, which can be used to study the space weather events and monitor the electromagnetic environment changes in the Earth's space. The FY3-D Ionospheric Photometer(IPM), launched on November 15, 2017, has a detection sensitivity which is greater than 150 counts / s / Rayleigh and a spatial field of view of 1.6 × 3.5 ° with high horizontal spatial resolution that will help to achieve the fine detection of the ionosphere. This report will analyze the FY3-D IPM detection results.At the same time,the report will introduce our research team’s work on the development and application of other payloads in the far ultraviolet band
Impact of weather regimes on wind power variability in western Europe
Authors: García-Herrera Ricardo , Garrido-Perez Jose M. , Ordóñez Carlos , Barriopedro David , Paredes Daniel
Published: March 2020

We have examined the applicability of a new set of 8 tailored weather regimes (WRs) to reproduce wind power variability in Western Europe. These WRs have been defined using a substantially smaller domain than those traditionally used to derive WRs for the North Atlantic-European sector, in order to maximize the large-scale circulation signal on wind power in the region of study. Wind power is characterized here by wind capacity factors (CFs) from a meteorological reanalysis dataset and from high-resolution data simulated by the Weather Research and Forecasting (WRF) model. We first show that WRs capture effectively year-round onshore wind power production variability across Europe, especially over northwestern / central Europe and Iberia. Since the influence of the large-scale circulation on wind energy production is regionally dependent, we have then examined the high-resolution CF data interpolated to the location of more than 100 wind farms in two regions with different orography and climatological features, the UK and the Iberian Peninsula.

The use of WRs allows discriminating situations with varied wind speed distributions and power production in both regions. In addition, the use of their monthly frequencies of occurrence as predictors in a multi-linear regression model allows explaining up to two thirds of the month-to-month CF variability for most seasons and sub-regions. These results outperform those previously reported based on Euro-Atlantic modes of atmospheric circulation. The improvement achieved by the spatial adaptation of WRs to a relatively small domain seems to compensate for the reduction in explained variance that may occur when using yearly as compared to monthly or seasonal WR classifications. In addition, our annual WR classification has the advantage that it allows applying a consistent group of WRs to reproduce day-to-day wind speed variability during extreme events regardless of the time of the year. As an illustration, we have applied these WRs to two recent periods such as the wind energy deficit of summer 2018 in the UK and the surplus of March 2018 in Iberia, which can be explained consistently by the different combinations of WRs.
Development of satellite-based Surface water stress index considering surface water balance
Authors: Yun Ye-Seul , Lee Yang-Won
Published: March 2020

The IPCC presented accelerated climate change and an increase in abnormal climate phenomena in the 21st century. This abnormal climate increases the frequency and intensity of extreme precipitation, resulting in changes in the water balance, such as precipitation and evaporation. Droughts are caused by prolonged water shortages, and it usually occurs in areas with subaverage rainfall. Drought is difficult to point precisely at the start and end, so its monitoring and forecasting are important to prepare for damage and mitigate impact. And although various satellite-based drought indices are being developed and used, it is still difficult to define drought quantitatively and to select a drought index suitable for the local situation. Currently, the drought indices used in Republic of Korea include SPI, which deals only with the water supply, and SPEI using the simple difference between precipitation and evapotranspiration. However, no standardized system of drought monitoring suitable for agricultural drought situations, such as the supply, consumption and impact of vegetation, has been established. However, it does not have a standardized system for monitoring drought agricultural drought suitable for situations such as the supply and demand of water and the impact on vegetation. this study tried to shows a new drought index that best expresses the drought in Korean cropland using long-term satellite data.
A novel nano-formulation to reduce the environmental dispersion of herbicides
Authors: Tosco Tiziana , Granetto Monica , Re Lucia , Audino Aurora , Serpella Luca , Fogliatto Silvia , Vidotto Francesco
Published: March 2020

The use of pesticides in agriculture has numerous advantages but also significant environmental drawbacks; The uncontrolled or excessive use of agrochemicals has progressively contributed to the contamination of environmental matrices, and in particular of soils and groundwater. To contribute solving these issues, an eco-compatible nano-formulation was recently developed by the authors to help controlling the environmental dispersion of Dicamba, a herbicide widely used to control broadleaf weeds; Dicamba is highly soluble and moderately volatile, but is less toxic and persistent compared to other competing herbicides. The proposed nano-formulation was developed using eco-compatible, low-cost materials, including natural clays an biopolymers, with the aim to reduce Dicamba volatilization (thus reducing dispersion in air, and consequently potential impacts on both workers and neighboring crops) and solubility (thus reducing infiltration during and after application, and consequently uncontrolled dispersion in the subsoil).  In this work, the results of laboratory and greenhouse tests are discussed, comparing the efficacy of the nano-formulation against the pure herbicide compound and a commercial Dicamba-based product, in terms of volatilization, mobility in porous media (both saturated and unsaturated) and efficacy in weed control. The column tests results are modeled using colloid transport software (namely MNMs and Hydrus) and used for the development of a preliminary field-scale model of herbicide application and dispersion in the subsoil. The work was developed in the framework of the project Nanograss, co-funded by Compagnia di San Paolo Foundation.
The RPW Time Domain Sampler (TDS) on Solar Orbiter: In-flight performance and first data
Authors: Soucek Jan , Uhlir Ludek , Lan Radek , Pisa David , Kolmasova Ivana , Santolik Ondrej , Krupar Vratislav , Kruparova Oksana , Maksimovic Milan , Kretzschmar Matthieu , Khotyaintsev Yuri , Chust Thomas
Published: March 2020

The Radio and Plasma Wave instrument (RPW) for Solar Orbiter includes a Time Domain Sampler sub-unit (TDS) designed to capture electromagnetic waveform measurements of high-frequency plasma waves and antenna voltage spikes associated with dust impacts. TDS will digitize three components of the electric field and one magnetic component at 524 kHz sampling rate and scan the obtained signal for plasma waves and dust impact signatures. The main science target of TDS are Langmuir waves observed in the solar wind in association with Type II and Type III solar bursts, interplanetary shocks, magnetic holes, and other phenomena. In this poster, we present the scientific data products provided by the TDS instrument and discuss the first data obtained during the commissioning phase. The first data will be used to evaluate the actual performance of the RPW TDS instrument.
MED-Star: Strategies and measures to reduce wildfire risk in the Mediterranean area
Authors: Salis Michele , Arca Bachisio , Pellizzaro Grazia , Ventura Andrea , Canu Annalisa , Casula Marcello , Del Giudice Liliana , Scarpa Carla , Schirru Matilde , Duce Pierpaolo
Published: March 2020

Wildfires represent a major threat to Mediterranean ecosystems and are responsible for relevant impacts to environmental, economic and social values. In the period 2010-2016, the cross-border Interreg Italy-France Maritime territory, which includes Sardinia, Corsica, Tuscany, Liguria and PACA Regions, had about 20,000 wildfire ignitions and a total burned area of about 122,000 ha. In the face of social and environmental conditions and risks of the Maritime Regions, strengthening and developing innovative common guidelines and systems of wildfire management, from the monitoring and forecast to suppression, can provide more effective solutions to the wildfire problem, and can help strengthen cross-border cooperation in case of days with high risk. This work is devoted to introduce the MED-Star project, and to describe his main activities and results, with a focus on the tasks and activities coordinated by the National Research Council of Italy, Institute of BioEconomy (CNR-IBE) of Sassari. MED-Star is a 3-years strategic project supported by the Interreg Italy-France Maritime Program 2014-2020, which is co-financed by the European Regional Development Fund (ERDF). MED-Star is closely linked to 4 joint simple projects (Intermed; Med-Coopfire; Med-Foreste; Med-PSS), which mainly focus on investments in small infrastructures for wildfire risk prevention and support to wildfire suppression operations. The MED-Star project aims to share and discuss fire management policies and the most advanced strategies that can reduce the risk associated with wildfires, also through the combination of joint action plans and pilot / demonstration actions. The partnerships of MED-Star and the related 4 simple projects include the main actors competent at the administrative, technical and scientific level on the wildfire topic in the Maritime area of cooperation, and are able to meet the abovementioned challenges, contributing to 1) the reduction of wildfire risk in the five Regions involved, 2) the definition of strategic and operational solutions, 3) the implementation of operational actions and investments for wildfire prevention, monitoring, forecast and suppression, and 4) the strengthening of joint early warning and risk monitoring systems.
Climate scenarios of the Gulf of Bothnia using a high-resolution regional ocean model (NEMO-SCOBI)
Authors: Fredriksson Sam , Siiriä Simo , Oikkonen Annu , Roiha Petra , Särkkä Jani , Hordoir Robinson , Höglund Anders , Hieronymus Jenny , Eilola Kari , Ruvalcaba Baroni Itzel , Arneborg Lars
Published: March 2020

How will the Gulf of Bothnia be impacted by future climate change? A changing climate will, in addition to warming, reduce the ice-season, change the salinity, sea level, and wave and current conditions. This will in turn have implications for eco systems, habitats, biodiversity, as well as human activities such as fishing, aquaculture, and wind parks. The SmartSea project aims to estimate the climate change impacts in this area. This study, which is part of the project SmartSea, assesses the changing physical and biogeochemical properties up to year 2059 using numerical experiments with forcing from two different Representative Concentration Pathways (RCP 4.5 and RCP 8.5) and four different global climate models. Here NEMO3.6 with LIM3 sea ice model is coupled to the biogeochemical model SCOBI. The model comprises the Gulf of Bothnia with a horizontal resolution of approximately one nautical mile.

The preliminary results comparing periods 1975-2005 and 2030-2059 and the pathway RCP4.5 and RCP8.5 show significant changes in sea ice conditions including a decrease of the ice season length, annual maximum ice volume, and extent of ice cover. In addition, the annual maximum ice volume is seen to arise earlier in the season. The temperature increases consistently, although the actual increase between the different simulations varies considerably. A general trend of decreasing salinity can also be seen. This is, however, less systematic than for ice conditions and temperature. The simulations indicate that the changes in both temperature and salinity are not spread evenly, but some areas will be affected more than others. The flow speed trends have been studied by comparing simulations for the period 1980-2005 and the pathway RCP4.5 and RCP8.5 for 2040-2059. The simulations indicate a rise in both local maximum flow speeds, as in average flow speeds, both in surface currents and depth averaged currents (barotropic currents).
Modelling of airborne Full Tensor Magnetic Gradiometry using data from the INFACT project
Authors: Nevalainen Jouni , Kozlovskaya Elena , Ranta Jukka-Pekka , Blanco Joan Marie , Kirsch Moritz , Gloaguen Richard , Schneider Michael , Kobow Jens
Published: March 2020

The measurement of the magnetic field has been a “backbone” geophysical method in mineral exploration since the 17th century. The existing instrumentation that measures Total Magnetic field Intensity (TMI) are a routinely used in ground, borehole and airborne surveys. In the TMI intensity data it is possible to observe certain signatures of magnetised objects, but retrieval of both magnetisation intensity and shape of 3-D magnetised objects from TMI can be difficult due to the vector nature of magnetisation and fundamental non-uniqueness of potential fields interpretation. Moreover, the presence of magnetic material in the host rock and/or presence of remanent magnetisation are challenges for TMI data interpretation.

Full Tensor Magnetic Gradiometry (FTMG) measurements provide the complete description of the magnetic field and hence an opportunity to get more information on the size, shape and material property of the magnetic rock mass. This is because the signatures in magnetic field originating from a specific magnetic object is observed in all independent components of magnetic field gradient tensor and thus, joint analysis of these tensor components constrains the number of possible magnetic models that fit the same data. In addition, observing the full tensor of magnetic field makes it possible to estimate the remanent magnetization with respect to the induced magnetization field if no a-priori information of remanent magnetization is available.

Highly sensitive magnetometers based on SQUID (Superconducting QUantum Interference Devices) technology has been successfully adopted in FTMG airborne measurements during the past decade. This achievement has given magnetic methods a new opportunity in terms of purely magnetic data modelling. In our work the benefits of interpretation of tensor airborne FTMG data are demonstrated through forward modelling and inversion with the grid search multiobjective global optimisation. As a case study, we consider airborne FTMG data measured with Supracon® JESSY STAR system in Northern Finland during the INFACT project.

Acknowledgements: This study has been done in the framework of EU Horizon 2020 funded INFACT project (webpage: https://www.infactproject.eu).
A user-friendly probabilistic earthquake source inversion framework for joint inversion of seismic, geodetic, and gravitational signals - The Grond toolkit
Authors: Heimann Sebastian , Isken Marius , Kühn Daniela , Vasyura-Bathke Hannes , Sudhaus Henriette , Steinberg Andreas , Petersen Gesa , Kriegerowski Marius , Daout Simon , Cesca Simone , Dahm Torsten
Published: March 2020

Seismic source and moment tensor waveform inversion is often ill-posed or non-unique if station coverage is poor or signals are weak. Three key ingredients can help in these situations: (1) probabilistic inference and global search of the full model space, (2) joint optimisation with datasets yielding complementary information, and (3) robust source parameterisation or additional source constraints. These demands lead to vast technical challenges, on the performance of forward modelling, on the optimisation algorithms, as well as on visualisation, optimisation configuration, and management of the datasets. Implementing a high amount of automation is inevitable.

To tackle all these challenges, we are developing a sophisticated new seismic source optimisation framework, Grond. With its innovative Bayesian bootstrap optimiser, it is able to efficiently explore large model spaces, the trade-offs and the uncertainties of source parameters. The program is highly flexible with respect to the adaption to specific source problems, the design of objective functions, and the diversity of empirical datasets.

It uses an integrated, robust waveform data processing, and allows for interactive visual inspection of many aspects of the optimisation problem, including visualisation of the result uncertainties. Grond has been applied to CMT moment tensor and finite-fault optimisations at all scales, to nuclear explosions, to a meteorite atmospheric explosion, and to volcano-tectonic processes during caldera collapse and magma ascent. Hundreds of seismic events can be handled in parallel given a single optimisation setup.

Grond can be used to optimise simultaneously seismic waveforms, amplitude spectra, waveform features, phase picks, static displacements from InSAR and GNSS, and gravitational signals.

Grond is developed as an open-source package and community effort. It builds on and integrates with other established open-source packages, like Kite (for InSAR) and Pyrocko (for seismology).
Relationship Between Ionosphere VTEC and Space Weather Indices for Machine Learning-based Model Development
Authors: Natras Randa , Schmidt Michael
Published: March 2020

Space weather can be the source of severe disturbances in the ionosphere, which can influence the performance and reliability of GNSS (Global Navigation Satellite Systems) technology and applications. In order to forecast and minimize these effects, accurate corrections need to be provided. This goal can be achieved by employing a precise model to describe the complex chain of space weather processes and the non-linear spatial and temporal variability of the Vertical Total Electron Content (VTEC) within the ionosphere, as well as, to include a forecast component considering space weather events in order to provide an early warning system. This is a challenging but important task of high interest for the GNSS community.

Artificial intelligence applications, such as Machine Learning (ML), are able to find and learn patterns from historical data to solve problems, which are too complex and/or too vast for humans. To develop an effective and high performance ML algorithm special consideration needs to be given to the selection of the input data. Data need to be selected in order to have sufficient information to describe and predict ionosphere VTEC variability accurately. Therefore, the study of space weather impacts for the integration of space weather information in forecast ionosphere models is of crucial importance.

In this study, the relationship between various indices, describing space weather and space climate, and ionosphere VTEC variability in different latitudes during longer time periods within the solar cycle 24 is examined. Conditions in space weather are described by solar wind, the magnetic field and plasma data, energetic proton fluxes, geomagnetic and solar activity indices provided by worldwide distributed observatories. VTEC data are derived from GNSS measurement from permanent stations, belonging to the EPN (EUREF Permanent Network) and the IGS (International GNSS Service) networks and selected in latitudinal range from 0° to 60°N. The period from year 2014 to year 2017 is used to relate space weather indices to VTEC variability, as well as, to train the ML model. In addition, periods of intense geomagnetic storms caused by different sources (coronal mass ejections and high-speed streams of solar wind from coronal holes), occurred during different seasons in this period are analyzed. The evolution and severity of storms are investigated in relation to the conditions in the solar activity, solar wind speed, interplanetary magnetic field and geomagnetic field together with their impact on the ionosphere VTEC. Obtained results of this investigation will be presented, as well as the methodology, goals and challenges for ML model development including preliminary results of an initial ML model.
Nonstationary Compound Weather Extremes in Canada based on Large Ensemble Climate Simulations
Authors: Najafi Mohammad Reza , Singh Harsimrenjit , Cannon Alex
Published: March 2020

Compound weather extremes including warm-wet and warm-dry events can lead to catastrophes such as wildfires, droughts and flooding. We use three large ensembles (3 × 50 members) of climate simulations to study the non-stationarity of compound events based on an ensemble pooling approach: the Canadian Regional Climate Model Large Ensemble (CanRCM4-LE), and the Canadian Large Ensembles Adjusted Datasets (CanLEAD1&2). The CanLEAD products include daily precipitation, maximum and minimum temperature from CanRCM4-LE that are bias-corrected using a novel statistical approach, which preserves the multivariate structure of the climate variables and corrects for univariate biases. Each ensemble member is validated against the NRCANmet observed data over Canada for 1951-2000 using a hierarchical Bayesian framework. Additionally, the performance of the models to mimic the dependence structure of the observation is tested using copulas. Extreme climate indices are estimated for a baseline period and changes in extremes are explored across four future warming scenarios corresponding to +1.5°C, +2.0°C, +3.0°C and +4.0°C warming above the pre-industrial period of 1850-1900. The ensemble pooling approach allows for the quantification of changes in the dependence structure and its subsequent effects on compound extremes in the future. 

Results show that the CanLEAD products can reduce warm and wet biases in CanRCM4-LE over the majority of Canadian regions in all seasons except for winter. The ensembles unanimously project significant warming and wetting trends over most of southern Canada excluding the Canadian Prairies in summer, which show a drying trend towards the end of the 21st century. The overall trend shows an increase in hot extremes in central and southeastern Canada and a significant increase in wet extremes in western coastal regions. Results from compound extreme analysis show that there is significant under-estimation of extremes when the dependence between temperature and precipitation is ignored. For example, a 100-year hot and dry event under the assumption of independence becomes a ~60-year event when the dependence is characterized using copulas.