bluuebunny/crossref_metadata_2025 huggingface dataset:
NEMO in Caribbean archipelago
Authors: Bezaud Marion , Deshayes Julie , Pous Stéphane , Jouanno Julien
Published: March 2021

Recently, the ocean dynamics of the Caribbean region has seen growing interest due the societal consequences of Sargassum beaching and storm surges, among other occasional extreme phenomena. Understanding the hydrodynamics in this area (mean currents and water mass properties, and mechanisms of variability) becomes urgent, to support operational developments forecasting the occurrence of such extreme phenomena, and also before one can foresee the local impacts of climate change. Building from an existing regional configuration at 1/12º (~10km), we implemented version 4.0.5 of NEMO to study the ocean dynamics of the Caribbean archipelago. This preliminary configuration is used to support sensitivity studies to atmospheric conditions, over the past 20 years. It also hosts AGRIF zooms to refine grid resolution up to 1km in the vicinity of the French islands, to enable a better understanding of the local dynamics.
Wildfire impact assessment through air quality monitoring in natural conservation areas and WRF-HYSPLIT coupled modelling
Authors: Castagna Jessica , Senatore Alfonso , Bencardino Mariantonia , D'Amore Francesco , Sprovieri Francesca , Pirrone Nicola , Mendicino Giuseppe
Published: March 2021

In the Mediterranean region, climate change-induced effects (i.e., increasing drought and heatwaves) are intensifying wildfire occurrences and severity. During 2017 the administrative region of Calabria (southern Italy) was affected by an exceptional wildfire season. This study evaluates the wildfire impact on some air quality parameters in two National Parks, located in the north and south of the region, respectively. Two sampling stations were considered for the impact assessment, namely the Monte Curcio Global Atmosphere Watch (GAW) regional station, located in the Sila National Park, and the Mammola rural-regional background station of the Regional Environmental Protection Agency of Calabria (ARPACal), in the Aspromonte National Park. To evaluate wildfire impact, a method based on the integration of ground-based observations (i.e., PM2.5, PM10, EBC, CO, and fire location) and WRF-HYSPLIT back-trajectories was applied. The WRF-HYSPLIT coupling allowed to reproduce high-resolution back-trajectories, improving the model accuracy in a complex orographic region such as the study area. Furthermore, wildfire impact on human health was qualitatively evaluated in terms of passively smoked cigarettes (PSC), related to the measured PM2.5 concentrations. During the examined period (summer 2017), the exposure to wildfire emissions resulted equivalent to approximately 6 PSC per day, for both stations. These outcomes, obtained at the regional scale in southern Italy, highlight that wildfire emissions, whose associated risks are still underestimated, are of concern for human health even in protected areas. Future studies, based on a more thorough chemical characterization and source apportionment methods, should be oriented towards assessing the wildfire contribution to air quality deterioration.
Historic simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model
Authors: Reese Ronja , Jenkins Adrian , Bull Christopher , Hellmer Hartmut , Winkelmann Ricarda
Published: March 2021

Large uncertainties in Antarctic sea level projections are related to ocean-driven melting (Seroussi et al., 2020; Jourdain et al., 2020; Reese et al., 2020; Edwards et al., in press) and the marine ice sheet instability (Robel et al., 2019). ‘Hindcasting’ simulations that follow the trajectory of the Antarctic Ice Sheet from pre-industrial conditions to present-day, are a useful tool to better constrain such uncertainties. We here perform historic simulations with the Parallel Ice Sheet Model. The simulations are forced by changes in the ocean and atmosphere from GCM output of CMIP5 as selected for ISMIP6 (Barthel et al., 2020). Sub-shelf melting is modeled using PICO (Olbers & Hellmer, 2010; Reese et al., 2018), with careful consideration of PICO’s parameters: the parameters for heat exchange across the ice ocean interface as well as the overturning strength are fitted with estimates of the melt sensitivity based on observations (Jenkins et al., 2018). Present-day observation of sub-shelf melting and mass loss inform parameter selection using an ensemble approach (Albrecht et al., 2020; Reese et al., 2020). The historic simulations provide an important basis to assess the future evolution and stability of Antarctic grounding lines. This work is done in the framework of the H2020 TiPACCs project.
Near-real-time flood forecasting for an urban coastal catchment: An approach in combination of numerical weather and 3-way coupled hydrodynamic flood modelling
Authors: Ghosh Mousumi , Paul Supantha , Karmakar Subhankar , Ghosh Subimal
Published: March 2021

The rapid increase in heavy precipitation flooding events highlights the need for efficient flood forecasting techniques to facilitate flood hydrological research and effective flood management by civic bodies. The current study aims to develop a near-real-time flood forecasting framework by integrating a 3-way coupled hydrodynamic flood model framework with numerical weather modelling based rainfall forecasts. The proposed framework has been demonstrated over Mumbai city in India, which is subjected to flooding every year during the monsoon months. A fine-resolution atmospheric simulation with the Weather Research and Forecasting (WRF) model has been performed for rainfall forecasts, which serve as an input to the flood model. To access the impact of urbanization on rainfall extremes, three scenarios are considered in the WRF simulations, i.e., WRF model: (1) without Urban canopy model (WRF-NoUCM), (2) coupled with a single-layer Urban canopy model (WRF-SUCM), and (3) coupled with a multi-layer Urban canopy model (WRF-MUCM). Further, a three-way coupled flood model has been developed where the MIKE 11 model (streamflow) with the drainage network (stormwater drains) and the MIKE 21 model (overland flow) have been considered for flood inundation and subsequently hazard mapping. In addition, the tidal elevation is provided along the coastline in the model setup. The flood maps developed by three WRF forecasted rainfall scenarios have been compared with that of the maps developed with observed rainfall. The extent to which the scenarios have been able to imitate the pattern and extent of flooding generated by observed rainfall has been investigated to decide the best scenario to be adapted in the comprehensive flood forecasting network. This state-of-art flood forecasting approach may be implemented in other flood-prone coastal regions as a major non-structural flood management strategy to reduce flood risk and vulnerabilities for the people dwelling in those regions.
Reliability tests of moment tensor inversion of anthropogenic seismicity
Authors: Tymińska Anna , Lizurek Grzegorz
Published: March 2021

Seismic moment tensor becomes part of basic seismic data processing. For anthropogenic events mostly common and available method to determine mechanism is amplitude inversion. However essential for correct amplitude inversion are good quality data. Factors commonly occurring in anthropogenic seismicity like high noise to signal ratio, low magnitude and shortage of seismic stations with unfavorable focal coverage can introduce undetected errors to inversion solution. In this work, synthetic tests for two seismic networks are presented to examine the reliability of P-wave first peak amplitude inversion for these areas. The synthetic tests of the noise influence on the results of full MT solutions were carried out for two surface networks monitoring anthropogenic seismicity: VERIS network in Vietnam and LUMINEOS network in Poland. Various mechanisms with double couple component variability from 10% to 100% were considered to take into account mechanisms caused by different types of human activity. High variability of solutions in tests shows that some spurious components cannot be avoided in full moment tensor solutions obtained for presented networks in certain cases.

This work was partially supported by research project no. 2017/27/B/ST10/01267, funded by the National Science Centre, Poland, under agreement no. UMO-2017/27/B/ST10/01267.
A compiled open-access geological map of Dronning Maud Land, Antarctica
Authors: Abu-Alam Tamer , Elvevold Synnøve
Published: March 2021

Geological mapping and investigation of the mountain chain in Dronning Maud Land (DML) has been carried out by a number of geologists from South Africa, Japan, India, Germany, Russia and Norway over the last 40-50 years. The produced geological maps of these teams are, for a large part, based on fairly old data which makes these maps inhomogeneous. The maps are at different scales, contain different levels of details, and the standards for classification of the rock units may also differ between the maps. This limits the ability to use these maps to draw an overview tectonic model of the evolution of Dronning Maud Land.

In this contribution, we present a newly compiled geological map and GIS database of the Dronning Maud Land. The map will be available soon as an open-access database, but the readers can test a test version of it at: https://geokart.npolar.no/Html5Viewer/index.html?viewer=Geology_DML. The geological importance of the Dronning Maud Land to understanding the evolution of the southern parts of the Gondwana supercontinent was the main motivation factor as the DML is considered as the missing link between the geology of South Africa, Australia and Indian subcontinent.

The new database covers the area between 20o W and 45o E and was compiled at a scale level of 1:250 000. However, the database provides another scale level of 1:5 000 000 to put the DML in the regional framework of the Gondwana. The geological map is descriptive based on the new topographic dataset of the Landsat 8. The project was based at the Norwegian Polar Institute from 2014 to 2018 and supported by a research grant from the Ministry of Foreign Affairs, Norway.
The Estrela UNESCO Global Geopark Science and Education Network for Sustainable Development
Authors: Gomes Hugo , Castro Emanuel , Vieira Gonçalo , Mora Carla , Echeverria Susana , Freitas Helena
Published: March 2021

The Network of Science and Education for Sustainable Development of the Estrela UNESCO Global Geopark, implemented in 2019, aims at supporting and fostering applied research in the Estrela Geopark’s territory, based on an articulated set of interdisciplinary working Groups with close links to the Higher Education Institutions and the national scientific and technological system, highlighting the entities that carry out research in mountain regions. Besides, it will also serve as a catalyst for the new generation of scientists who will benefit from the more than 2,200 km2 of this territory as a living laboratory.

The Network presents a dynamic structure, through a set of nuclei (working groups), promoting science and education, and developing scientific research in complementary areas. Each Nucleus is coordinated by a Responsible Researcher (RR) and includes a team appointed by him. The Nuclei develop their R & D activity in articulation with public and private research units and technology centres, whose activity is developed in lines and projects closely related to the Estrela Geopark. Its priority activities will be defined within the framework of the Estrela Geopark’s Strategic Plan for Science, as well as within the premises of UNESCO, with priority in the following areas: Geology and Geomorphology, Landscape, Culture and Heritage, Climate and Climate Change, Biodiversity and Ecology, Environment and Natural Resources, Territory Planning and Risks, Tourism, Leisure and Sustainable Development.

Thus, this network aim at creating activities that promote science, education and scientific knowledge, in a collaborative way, based on the establishment of medium and long-term strategic partnerships between different actors of the territory and institutions that carry out research in the several themes, having as main objectives the cooperation in the identification of challenges, joint planning of activities, the definition of projects, the development of studies on the territory of the Estrela, the sharing of resources and infrastructures and the mobility and / or exchange of resources, with the aim of transferring, sharing and disseminating knowledge.

This Network promotes 5 working groups of science and education in: Climate Change; Water Resources; Biodiversity and Ecology; Tourism and Sustainability; Geodiversity and Geoconservation.

This holistic strategy aims at putting scientific knowledge at the service of the communities, through an effective citizen science, implementing various activities with the direct involvement of the communities and its promotion.
Temporal seismic velocity changes during the 2020 rapid inflation at Mt. Thorbjorn-Svartsengi, Iceland, using ambient seismic noise
Authors: Cubuk Sabuncu Yesim , Jonsdottir Kristin , Caudron Corentin , Lecocq Thomas , Parks Michelle Maree , Geirsson Halldor , Mordret Aurelien
Published: March 2021

The Reykjanes peninsula, SW Iceland, was struck by intense earthquake swarm activity that occurred in January-July 2020 due to repeated magmatic intrusions in the Reykjanes-Svartsengi volcanic system. GPS and InSAR observations confirmed surface deformation centered near Mt. Thorbjorn, and during the unrest period, approximately ~14,000 earthquakes (-2≤M≤4.9) were reported at the Icelandic Meteorological Office (IMO). We investigate the behavior of the crust as a response to these repeated intrusions to provide insights into volcanic unrest in the Reykjanes peninsula. Our study presents temporal seismic wave velocity variations (dv/v, in percent) based on ambient noise seismic interferometry using continuous three-component waveforms collected by IMO, (http://www.vedur.is) for the period from April 2018 to November 2020. The state-of-the-art MSNoise software package (http://www.msnoise.org) is used to calculate cross-correlations of ambient seismic noise and to quantify the relative seismic velocity variations. We observe that magmatic intrusions in the vicinity of Mt. Thorbjorn-Svartsengi have considerably reduced the seismic wave velocities (dv/v, -1%) in the 1-2 Hz frequency band. Seismic velocity changes were compared with local seismicity, GPS and InSAR data recorded close to the repeated intrusions, and modelled volumetric strain changes. We found a good correlation between the dv/v variations and the available deformation data. The Rayleigh wave phase-velocity sensitivity kernels showed that the changes occurring at depths down to ~3-4 km in the crust were captured by our measurements. We interpret the relative seismic velocity decrease to be caused by crack opening induced by intrusive magmatic activity. Monitoring the Mt. Thorbjorn-Svartsengi volcanic unrest is crucial for successful early warning of volcanic hazards since the center of uplift is only 2km away from a fishing village and major infrastructure in the area, such as water supply and geothermal power. For the first time in Iceland, we have provided near-real-time dv/v variations to obtain a more complete picture of this magmatic activity. Our findings are supported by the analysis of other primary monitoring streams. We propose that this technique may be useful for early detection of future intrusions/increased magmatic activity. This study is supported by the Icelandic Research Fund, Rannis (Grant No: 185209-051).
Detailed Calibration of the Off-Axis Optical Characteristics for the X-Ray Telescope onboard Hinode
Authors: Shin Junho , Kano Ryouhei , Sakurai Takashi , Kim Yeon-Han , Moon Yong-Jae
Published: March 2021

The X-Ray Telescope (XRT) onboard the Hinode satellite has a specially designed Wolter type grazing-incidence (GI) optics with a paraboloid-hyperboloid mirror assembly to measure the solar coronal plasma of temperatures up to 10 MK with a resolution of about one arc sec. One of the main purposes of this scientific mission is to investigate the detailed mechanism of energy transfer processes from the photosphere to the upper coronal region leading to its heating and the solar wind acceleration. An astronomical telescope is in general designed such that the best-focused image of an object is achieved at or very close to the optical axis, and inevitably the optical performance deteriorates away from the on-axis position. The Sun is, however, a large astronomical object and thus targets near the limb of full-disk images are placed at the outskirt of the field of view. The design of a solar telescope should thus consider the uniformity of imaging quality over a wide FOV, and it is particularly so for X-ray telescopes whose targets can be in the corona high above the limb.

 

We will explain in this presentation the importance of detailed calibration of the off-axis optical characteristics for Hinode/XRT. It have been revealed that the scattered light caused by the GI mirror surface has a power-law distribution and shows an energy dependence. We will also introduce the basic scheme of how the level of scattering wing is determined and connected to the core from the analysis of highly saturated in-flight data. Vignetting is another important optical characteristics for describing the telescope's performance, which reflects the ability to collect incoming light at different locations and photon energies. We have evaluated the vignetting effect in Hinode/XRT by analyzing the ground experimental data and found that the degree of vignetting varies linearly from the optical center and its pattern shows an energy dependence. Many interesting results on the calibration of Hinode/XRT optical characteristics will be introduced and discussed thoroughly. 
Reconstruction constraints on the Estero Parraguirre ice-rock avalanche in 1987, Central Andes of Chile: New insights from remote sensing and numerical modeling.  
Authors: Bruckner Thomas , Farías-Barahona David , Fürst Johannes , Mergili Martin , Sepulveda Sergio , Pena Humberto , Casassa Gino , Braun Matthias
Published: March 2021

 On 29th of November of 1987, a large ice-rock avalanche occurred in a permafrost area of the central Andes of Chile. This event has been considered one of the most destructive events in that area in the last decades. The ice-rock avalanche initiated at an elevation of 4350 m, above the Estero Parraguirre. Due to the large amounts of ice and snow and the high potential energy, this avalanche developed into a debris flow propagating down the valley, reaching a travel distance of approx. 57 km after 2 hours. On the way, many people lost their lives, and two hydroelectric power plants were destroyed. The avalanche was likely triggered by warm temperature anomalies and snow build-up at high elevation linked to the concurrent and strong El Nino event in 1987.

In this study, we use old topographic maps and aerial photographs, acquired just a few days after the event, and satellite imagery to constrain the trigger volume and to accurately compute the general mass displacement. A physically-based multi-phase mass flow model is employed to retrace the dynamics and characteristics of this debris-flow event. Previous studies suggested a trigger volume of about 6 x 106 m3. After entrainment along the flow path, the debris flow reached a total volume of 15 x 106 m3. First results of our study suggest that the trigger volume was significantly larger than previously thought. The next step is to shed light on possible entrainment scenarios, which will be constrained by and assessed against the observed elevation changes/mass displacement.

The reconstruction of this event is crucial to better assess future events and thus to develop successful mitigation strategies.
Nonlinear Fourier Analysis for Two-Dimensional Ocean Surface Waves Described by the Zakharov Equation
Authors: Osborne Alfred R.
Published: March 2021

The physical hierarchy of two-dimensional ocean waves studied here consists of the 2+1 nonlinear Schrödinger equation (NLS), the Dysthe equation, the Trulsen-Dysthe equation, etc. on to the Zakharov equation. I call this the SDTDZ hierarchy. I demonstrate that the nonlinear Schrödinger equation with arbitrary potential is the natural way to treat this hierarchy, for any member of the hierarchy can be determined by an appropriate choice of the potential. Furthermore, the NLS equation with arbitrary potential can be written in terms of two bilinear forms and thereby has one and two-soliton solutions. To access the inverse scattering approach, I find a nearby equation which has N-soliton solutions: Such an equation is completely integrable by the IST on the infinite plane and by finite gap theory for periodic boundary conditions. In this way the entire SDTDZ hierarchy is closely related to a nearby integrable hierarchy which I refer to as the iSDTDZ hierarchy. Every member of this hierarchy has solutions in terms of ratios of Riemann theta functions and therefore every member has general spectral solutions in terms of quasiperiodic Fourier series. This last step occurs because ratios of theta functions are single valued, multiply periodic meromorphic functions. Once the quasiperiodic Fourier series are found, one can then invert these to determine the Riemann spectrum, namely, the Riemann matrix, wavenumbers, frequencies and phases. This means that the solutions of the nonlinear wave equations of the iSDTDZ hierarchy are generalized Fourier series indistinguishable from those of Paley and Weiner [1935] and therefore allows one to classify nonlinear wave motion in terms of a linear superposition of sine waves. How do the generalized quasiperiodic Fourier series differ from ordinary, standard periodic Fourier series? This can be seen by recognizing that the frequencies are incommensurable, and the phases can be phase locked. The nonlinear Fourier modes are Stokes waves and the coherent structure solutions are nonlinearly interacting, phase-locked Stokes waves, including breathers and superbreathers. Other types of coherent packets include fossil breathers and dromions. Techniques are developed for (1) numerical modeling of ocean waves (a fast algorithm for the Zakharov equation) and for (2) the nonlinear Fourier analysis of two-dimensional measured wave fields and space/time series (a 2D nonlinear Fourier analysis, implemented as a fast algorithm called the 2D NFFT). Examples of both applications are discussed.
Joint ESA and NASA Imaging Spectrometer Airborne Campaign to Support CHIME and SBG
Authors: Green Robert , Rast Michael , Schaepman Michael , Hueni Andreas , Eastwood Michael
Published: March 2021

In 2018 a joint ESA and NASA airborne campaign was orchestrated with the University of Zurich to advance cooperation and harmonization of algorithms and products from imaging spectrometer measurements.  This effort was intended to benefit the future candidate European Copernicus Hyperspectral Imaging Mission for the Environment (CHIME) and NASA Surface Biology and Geology mission. For this campaign, the Airborne Visible/Infrared Imaging Spectrometer Next Generation was deployed from May to July 2018.  Twenty-four study sites were measured across Germany, Italy, and Switzerland.  All measurements were rapidly calibrated, atmospherically corrected, and made available to NASA and ESA investigators.  An expanded 2021 campaign is now planned with goals to: 1) further test and evaluate new state-of-the-art science algorithms: atmospheric correction, etc; 2)  grow international science collaboration in support of ESA CHIME and NASA SBG; 3) test/demonstrate calibration, validation, and uncertainty quantification approaches;  4) collect strategic cross-comparison under flights of space missions: DESIS, PRISMA, Sentinels, etc.  In this paper, we present an overview of the key results from the 2018 campaign and plans for the 2021 campaign.

 
Prospecting urban rooftop solar farm potential in Dublin, Ireland
Authors: Verma Ankit , Connolly John , O'Connor Noel
Published: March 2021

The development of a sustainable and renewable energy system is a significant challenge for Ireland. In line with UN and EU policies, Ireland aims to transition to a competitive, low carbon, climate-resilient and environmentally sustainable economy by 2050 (Project Ireland 2040 National Planning Framework). Ireland is committed to an aggregate reduction in CO2 emissions of at least 80% (compared to 1990 levels) by 2050 across the electricity generation, built environment and transport sectors. Renewable energy can help Ireland reduce GHG emissions and carbon footprint as energy demands grow. It also reduces dependencies on fossil fuels as well as increases energy supply security.

According to the Sustainable Energy Authority of Ireland’s “Energy in Ireland 2020” report, 36.5% of electricity demand was met by renewable energy sources in 2019. Wind energy contributes 32% while solar energy contributes to <1%. Significant investment has been made in Ireland’s wind sector; however, the solar energy sector is relatively new. Ireland has the second-lowest total installed and cumulated solar photovoltaic (PV) capacity in the EU with just 36 MW or 7.3 W per inhabitant. (EurObserv'ER 2019).

Solar prospecting is necessary to identify optimum locations where solar farms can be established. Commercial and industrial building rooftops in urban areas offer a suitable location for establishing rooftop solar farms due to good connectivity with the electricity grid and proximity to users. Here we present an urban solar prospecting study in Dublin, Ireland.

A very high-resolution geospatial dataset was acquired for 47 industrial areas covering 53.3 km2. The data comprises of very high-resolution aerial images (12.5 cm/pixel) and digital surface model (DSM) (25 cm/pixel).

The high-resolution DSMs were used to model solar irradiation on building rooftops in ArcGIS Pro using the area solar analyst tool. These models were optimised for Irish conditions using Met Éireann solar radiation data for Dublin. The maximum solar insolation received in Dublin is 1000-1050 kWh/m2. The results demonstrate that there is potentially a large amount of commercial and industrial rooftop surface area available for PV installation in Dublin. These rooftops can generate a significant amount of electricity and help to offset CO2 emissions.

 
Water Sensitive Cities: integrated approach to enhance urban flood resilience in Parma (Northen Italy)
Authors: Dada Arianna , Urich Christian , Pezzagno Michèle , Grossi Giovanna
Published: March 2021

The climate change of the last half century is globally causing an increasingly in violent meteorological phenomena. Cities are experiencing the pressures of these phenomena and they are facing many challenges - economic, social, health and environmental.

Over the coming decades the population growth and the rapid urbanization will bring to a tumultuous growth of the cities that will become more and more vulnerable, especially to flood hazards.

In order to make our urban water systems more effective to these challenges new water management strategies must be developed. The complexity of this challenge calls for the integration of knowledge from different disciplines and collaborative approaches.

The concept of Water Sensitive Cities is one of the starting points for developing new techniques, strategies, policies, and tools to ensure a better liveability, sustainability, and resilience of the cities.

In this study, the DAnCE4Water model to promote the development of Water Sensitive Cities, was applied to Parma, an Italian town that faced serious water issues in the last years. Through the model the efficiency of new decentralized technologies, as green roofs and porous pavement, and their integration with the existing centralized technologies (sewerage), was estimated.

The first phase of the study concerned the analysis of the current state of the sewerage network and the relative critical issues. Flow rates and the amount of surface runoff were calculated using the SWMM modelling software.

In the second phase three hypothetical different scenarios were created by adopting different intervention strategies. The first scenario was created by using green roofs for a percentage of existing buildings in the urban area equal to 30%; the second scenario was created by adopting the porous pavement technology. For the third scenario, a possible urban development was simulated, with its consequent population, without adopting any flood risk mitigation strategy. A hydraulic study was carried out for each scenario highlighting the differences in terms of runoff formation and percentage of infiltration.

The integrated approach enables a city to test its current water management practices and policy, it helps cities to identify their short and long term goals to enhance water sensitivity, it gives a quantification of benefits and costs and it provides an estimate,  still in the design phase, of the effectiveness of possible strategies under different scenarios like climate changes, changes in the societal needs and urban changes by modelling the complex dynamics between societal system, urban environment and the urban water system.
Intraplate deformations, topographic evolution and sediment production of Western Europe from 40 to 5 Myrs
Authors: Guillocheau Francois , Robin Cécile
Published: March 2021

Western Europe experienced a major rift system initiated during Bartonian times (41 Ma). This evolution is coeval with long wavelength deformations (several hundreds of kilometers) that control the topography and the sediment production beyond the rift. The climate during this time interval was first increasingly arid and then wetter.

This study is based on both landform and sediment analysis of southern England, France, Belgium and western Germany. The landforms are mainly large pediments, dated by the intersection with sediments deposited in low to high subsiding areas and volcanism. A set of paleogeographic maps with paleotopographic reconstructions, is used to constrain the uplifting and subsiding areas, their wavelength and the critical periods of intraplate deformations.

The main periods of deformations and sedimentary systems changes area as follow.

41Myrs (base Bartonian) was the beginning of a major tilting of Western Europe with subsidence of France and uplift of the Brabant/Ardennes/Rhenish Massif. Even a dense network of basement faults was reactivated, biochemical sedimentation prevailed.

35-31Myrs (Late Priabonian-Early Rupelian) initiated a period of general subsidence even along the Ardennes/Rhenish Massif and the French Massif Central. Two major marine floodings are recorded, with a differential preservation according to the balance between deformation and eustasy.

27-25Myrs (Chattian) was a period of uplift of Western Europe except the Aquitaine Basin, followed by a relaxation favoring eustatic floodings in (very) low subsiding domains. Chattian siliciclastic deposits are preserved as lowstand wedges in the surrounded basins (North Sea, Atlantic Margin).

14-11Myrs (Serravallian-Early Tortonian) initiated the overall uplift of Western Europe, still operating today. This is the beginning of a period of major denudation in southern England, Western Germany (SW Germany flat - “Stufenland”) and along the southern limb of the Franch Massif Central.

The causes and the consequences in term of sediment production are discussed.
Improving understanding of hydrological and biogeochemical processes controlling the effectiveness of two-stage ditches in reducing eutrophication
Authors: Hallberg Lukas , Bieroza Magdalena
Published: March 2021

Combating eutrophication requires holistic mitigation measures aimed at reducing agricultural losses of nitrogen (N) and phosphorus (P) from field sources to aquatic systems. This need will become critical in the future as increased flashiness, expected from changing climate and growing food demand, will further accelerate N and P pollution. Agricultural headwater streams are the main entry point of diffuse nutrient and particulate losses to stream networks. These streams are often channelized with a trapezoidal design, which effectively convey excess water from fields but also nutrients and soil particles to recipient water bodies. In addition, trapezoidal ditches with steep stream banks are sensitive to erosion and require routinely dredging to maintain their drainage function.

This project will advance the knowledge of processes governing nutrient and sediment retention in agricultural streams in Sweden by focusing on two-stage ditches (SDs) which are new type of mitigation measure. In SDs, the stream channel is surrounded by incised floodplains that increase the hydrological connectivity between stream and riparian zone during high flows. When floodplains are inundated, water residence time increases which allow deposition of suspended particles and biogeochemical processing of nutrients and organic matter. With slower water velocities in SDs at high flows, bank erosion may also be minimized. Existing studies in the US and Finland have found that SDs can mitigate N, P and sediment losses, compared with traditional trapezoidal ditches. This project is the first of its kind to evaluate the efficiency and stability of 10 different SDs in Swedish conditions over 3 years, situated in catchments with diverse agricultural land use and soil characteristics.

In this presentation, we show the details of experimental setup and preliminary results. A sampling has been setup in SD reaches to monitor seasonal sedimentation rate and aggradation since construction. This is coupled with both low- and high-frequency water quality monitoring and measurements of nitrogenous gas emissions from denitrification in sediments. We discuss the success factors in terms of placement and design of SDs to enhance ecosystem functions (self-purification, erosion and flood prevention). These factors determine SDs’ effectiveness in retention of water, N, P and sediments and their suitability as mitigation measure.
Direct numerical simulation of droplet-mediated exchange fluxes in the marine atmospheric boundary layer
Authors: Druzhinin Oleg
Published: March 2021

Now it is a common knowledge that at sufficiently strong winds, sea-spray droplets interfere with  turbulent exchange processes occurring between atmosphere and hydrosphere. The results of field and laboratory experiments show that mass fraction of air-borne spume water droplets increases with the wind speed and their impact on the marine atmospheric boundary layer may become significant. The contribution of droplets to the momentum and sensible and latent heat fluxes may be crucial for our understanding of conditions favorable for the development of anomalous weather phenomena such as tropical hurricanes and polar lows. Phenomenological models and bulk algorithms are mostly based on hypothetical assumptions concerning the properties of droplet-air interaction which strongly influence the accuracy of their forecast. Lagrangian stochastic modeling also requires an adhoc knowledge of the properties of turbulent fields ‘seen’ by the droplets along their trajectories. These details of droplet-air interaction are difficult to measure in lab conditions and can be gleaned via direct numerical simulation (DNS). DNS solves primitive equations for the carrier air in the Eulerian frame and of droplets motion in a Lagrangian frame and accounts for the two-way coupling of momentum, heat and moisture between the carrier and dispersed phases, and allows us to investigate the droplet contribution to the exchange fluxes under different injection conditions and flow bulk parameters. The results obtained for different conditions show us that droplets dynamics and their contribution to the momentum and heat fluxes are controlled by many factors including droplets velocity at injection, the gravitational settling velocity, surface wave slope, bulk relative humidity and temperature of the atmospheric boundary layer as compared to the sea surface conditions.

This work is supported by the Ministry of Education and Science of the Russian Federation (Task No. 0030-2019-0020). Numerical algorithms were developed under the support of RFBR (20-05-00322, 21-55-52005, 18-05-60299). Postprocessing was performed under the support of the Russian Science Foundation (No. 19-17-00209).
An evaluation of kilometre scale ICON simulations of mixed-phase stratocumulus over the Southern Ocean during CAPRICORN
Authors: Ramadoss Veeramanikandan , Pfannkuch Kevin , Protat Alain , Huang Yi , Siems Steven , Possner Anna
Published: March 2021

Stratocumulus (Sc) clouds cover between 25% to 40% of the mid-latitude oceans, where they substantially cool the ocean surface. Many climate models poorly represent these marine boundary layer clouds in the lee of cold fronts in the Southern Ocean (SO), which yields a substantial underestimation of the reflection of short wave radiation. This results in a positive mean bias of 2K in the SO. The representation of stratocumulus clouds, cloud variability, precipitation statistics, and boundary layer dynamics within the ICON-NWP (Icosahedral Nonhydrostatic – Numerical Weather Prediction) model at the km-scale is evaluated in this study over the SO.

Real case simulations forced by ERA5 are performed with a two-way nesting strategy down to a resolution of 1.2 km. The model is evaluated using the soundings, remote sensing and in-situ observations obtained during the CAPRICORN (Clouds, Aerosols, Precipitation, Radiation, and Atmospheric Composition over the Southern Ocean) field campaign that took place during March and April 2016. During two days (26th to 27th of March 2016), open-cell stratocumuli were continuously observed by the shipborne radars and lidars between 47oS 144oE and 45oS 146oE (South of Tasmania). Our simulations are evaluated against the remote sensing retrievals using the forward simulated radar signatures from PAMTRA (Passive and Active Microwave TRAnsfer).

The initial results show that the observed variability of various cloud fields is best captured in simulations where only shallow convection is parameterised at this scale. Furthermore, ICON-NWP captures the observed intermittency of precipitation, yet the precipitation amount is overestimated. We further analyse the sensitivity of the cloud and precipitation statistics with respect to primary and secondary ice-phase processes (such as Hallett–Mossop and collisional breakup) in ICON-NWP. Both processes have previously been shown to improve ice properties of simulated shallow mixed-phase clouds over the Southern Ocean in other models.
Forecast based Financing for Food Security : from early warning to early action in Eastern Africa
Authors: Guimarães Nobre Gabriela , Wens Marthe , Van den Homberg Marc
Published: March 2021

The project “Forecast based Financing for Food Security” (F4S) aims to provide a deeper understanding of how key drivers of food insecurity can be forecasted early enough to enable the trigger of humanitarian action in pilot areas in Ethiopia, Kenya, and Uganda. In combination with the knowledge being produced about early warning and forecasting, F4S also wants to inform early action (e.g. ex-ante cash transfers) that can reduce the risk of food insecurity. F4S has been achieving this goal through three main pillars:  (i) modelling, (ii) local knowledge and (iii) cost-benefits analysis.

This PICO presentation shares the lessons learnt and results of the F4S project. Moreover, it  hopes to trigger the discussion on how the scientific community together with local stakeholders and communities can co-produce knowledge that is relevant to local action, focussing on three result areas.

(i) The impact-based forecasting model to understand the key drivers of food insecurity in agricultural, agro-pastoral, and pastoral regions. Simple to more complex Machine Learning algorithms have been developed, applied and benchmarked. These algorithms were used to forecast, 6 to 1 months ahead, key indicators of food insecurity such as the shortage of calories and the transitions in IPC classes. Local knowledge was used to inform the selection of the predictors of the Machine Learning algorithm.

(ii) The results of a household survey and individual choice experiments among 600 household members of vulnerable communities. The survey collected local knowledge on early warning (food insecurity triggers) and early actions traditionally taken to lessen food insecurity. The novel choice experiment consisted of giving potential beneficiaries of ex-ante cash transfers the choice between different timings and frequencies of cash transfers for different drought and food security scenarios. The results provided a better understanding of people’s willingness to invest in risk reduction actions and individual preferences on key design elements of cash transfer mechanisms.

(iii) The evaluation of the cost-effectiveness of different cash transfer mechanisms that investigates how cash transfer programs can achieve a significant reduction in costs if cash is disbursed prior to the food insecurity occurrence.

This knowledge, as produced on the three areas above, is being currently used to improve the design of ex-ante cash programs. In addition to yielding significant cost savings, the project has found that cash transfer programs can be a more dignified solution when disbursed early enough. Cash transfer programs have the potential to increase the range of early action by beneficiaries that ultimately can reduce the risk of food insecurity and possibly malnutrion in vulnerable communities.
Towards Inter-Technique Co-Location of GNSS and VLBI Observations
Authors: Herrera Pinzón Iván Darío , Rothahcer Markus
Published: March 2021

The current realisation of the ITRF2014, features the estimation of polar motion (x-pole and y-pole) based on the combination of the four space geodetic techniques, whereas polar motion rates are based on two techniques, and UT1-UTC and LOD are taken only from the solution of a single technique (VLBI). Moreover,the combination of troposphere parameters (from VLBI and GNSS) with tropospheric ties and the combination of common clocks at the fundamental sites are not yet exploited in this combination strategy. Therefore, a rigorous combination of all common parameter types, with consistent Earth Orientation Parameters (EOPs) and with appropriate inter-technique tropospheric and clock ties, is still a considerable way to go.

The guiding principle for a rigorous combination is that all parameter types common to more than one space geodetic observation technique should be combined, including their full variance-covariance information as well as the corresponding ties. Based on this fact, and keeping in mind that both, GNSS and geodetic VLBI are based on microwave frequencies, and that their physical models and their parameter types (site coordinates and velocities, troposphere estimates, EOPs and -possibly- clock estimates) are closely related, we used data from the CONT17 campaign to study the benefits to be expected from a more rigorous combination approach, and we developed a processing scheme, based on a tailored version of the Bernese V5.2 software, for the consistent estimation of all EOPs, with daily and sub-daily resolution of polar motion and UT1-UTC, and for realising inter-technique tropospheric ties. We discuss the challenges and results of this rigorous inter-technique combination of VLBI and GNSS observations, and provide evidence of the need of such an approach.
Tectonic influence of Large Igneous Provinces on source-to-sink systems, the case study of Shetland during the Palaeocene - Preliminary results
Authors: Albanese Valore Lucas , Haug Eide Christian , Oftedal Sømme Tor
Published: March 2021

The source-to-sink approach to sedimentology has become an increasingly valuable approach for addressing how external and internal forcing mechanisms are tied together in time and space. Processes that are initiated deep within the lower mantle can eventually propagate and affect shallow crustal sedimentary systems. This is important to predict the presence of reservoirs in areas of little data, and to interpret the sedimentary record in terms of climate and tectonic settings during deposition. To address this issue, we will study the Early Palaeogene succession of the East Shetland Platform in the North Sea, which was deposited during the emplacement of the Icelandic Plume. The plume’s activity is hypothesized to be the cause of a major uplift cycle in the continental source areas, which is coeval to a sharp increase in sedimentation rates recorded in the East Shetland Platform during the Palaeocene. However, this relationship is still in need of accurate constraints derived from data with better spatial and temporal resolution, particularly due to overlapping climatic and tectonic controls, regional-to-local variations in sediment supply systems and overall gaps in the sedimentary record. This correlation can benefit from high-quality 3D seismic data on the platform, especially due to an exceptional preservation of shelf-edge geometries that are absent elsewhere. Using different 3D and 2D seismic surveys, well data and biostratigraphic data from the Shetland Platform and the North Sea, we will quantify sediment volumes supplied through time. The observed sediment volumes will be investigated using models of dynamic topography, plume activity and paleoclimatic data to closely relate supplied volumes to changes in relief, catchment geometries, precipitation and other key forcing parameters. Ultimately, we aim to investigate the relative influence of both tectonics and climate, as both long term (mantle dynamics) and short term (Palaeocene-Eocene Thermal Maximum) have been interpreted to play an important role in this system.

 
Data-driven reservoir storage and release scheme parameterized for all large dams of the United States
Authors: Turner Sean , Voisin Nathalie , Steyaert Jennie , Condon Laura
Published: March 2021

Large-scale hydrological and water management models (LHMs) require reservoir operations schemes to simulate the influence of human systems on natural earth systems. A typical challenge for representing hundreds of reservoirs in a single LHM is creating consistent scheme capable of simulating realistic water storage and release amidst the diversity in the type of operations. We present a new dataset of observed reservoir operations that includes daily storage, inflow, outflow, evaporation, and elevation level time series for approximately 600 large reservoirs (> 0.1km3 storage) located throughout the conterminous United States. These data have been collected through a combination of mining water agencies databases and formal Freedom of Information (FOI) requests. The newly compiled data are used to derive data-driven simulation schemes, which we compare against contemporary, generic approaches adopted in state-of-the-art LHMs. With release-centric reservoir operations scheme usually more sensitive to biases in hydrologic simulations, we introduce a parsimonious scheme that defines storage targets using harmonic functions that can also be easily extrapolated to un-measured dams. This extrapolation allows us to develop realistic reservoir operations for all 1945 large reservoirs in the conterminous United States currently represented in the Global Reservoir and Dams database.