bluuebunny/crossref_metadata_2025 huggingface dataset:
INFÂNCIAS (IN) VISIBILIZADAS: REFLEXÕES SOBRE A CRIANÇA NEGRA NA HISTÓRIA DE VILHENA-RO
Authors: Rohden Josiane Brolo , Batista Daniella Cristina dos Santos de Souza , Silva Jaqueline Souza , Boing Vera Lucia Aquino , Silva Vanessa de Oliveira da
Published: March 2021

Esse trabalho busca promover a visibilidade da criança negra no cotidiano da história da Educação de Vilhena — RO, entre os anos de 1960 a 1980. Sabe-se que na história, as crianças não receberam a visibilidade merecida por seus papeis sociais, culturais, e nesse contexto, as crianças negras são praticamente ainda mais invisibilizadas. Poucos registros contam com a presença de crianças não brancas durante o processo de colonização e migração de Vilhena, como se não houvesse a presença de povos de diferentes etnias. A história contada é branca, sem pretos, pardos, sem os povos originários da floresta. Como se trata de uma pesquisa que também envolve o tema da diversidade cultural, essa investigação busca contribuir para a discussão de ruptura do modelo eurocêntrico na educação e sucessivamente na análise histórica e social da participação do afrodescendente na construção de uma educação multicultural na escola brasileira. A execução metodológica no âmbito da Nova História Cultural (NHC) se utiliza de fontes documentais e fotografias históricas de infâncias dos migrantes que vivenciaram tal experiência no cenário em estudo.
DIRETIVAS ANTECIPADAS DE VONTADE: O EXERCÍCIO DA AUTONOMIA EXISTENCIAL DO MENOR EM ESTADO TERMINAL
Authors: Torquato Jennifer Silveira , Soares Mirelle Fernandes
Published: March 2021

O presente trabalho se propôs a analisar o exercício da autonomia existencial do paciente menor de idade para elaborar uma Diretiva Antecipada de Vontade, tendo como objetivo verificar a possibilidade de garantir que a vontade da criança e do adolescente em estado terminal seja concretizada. Para tanto, foi utilizado o método hipotético-dedutivo, com coleta de dados em doutrinas, revistas, artigos, legislação e jurisprudência sobre o tema.
CONSTRUÇÃO DO PROJETO POLÍTICO PEDAGÓGICO DA ESCOLA NA PERSPECTIVA DO ORIENTADOR EDUCACIONAL
Authors: Campos Edineia Barros da Silva
Published: March 2021

O presente estudo tem como finalidade refletir sobre o papel do Orientador Educacional no contexto atual com vistas à construção do Projeto Político Pedagógico na escola. Entende-se que o Projeto Político Pedagógico é um documento norteador das ações sócio – pedagógicas desenvolvidas na instituição educacional e que o mesmo deve ser o resultado de um trabalho de reflexão coletiva. Ressalta-se que este trabalho não tem a pretensão de trazer orientações quanto à elaboração do Projeto Político Pedagógico, visto que há um vasto número de documentos que normatizam tal prática, mas tecer algumas considerações sobre o mesmo, na perspectiva do Orientador Educacional, no que se refere a elaboração do Projeto Político Pedagógico nas escolas públicas. Essa pesquisa buscou fazer uma revisão bibliográfica, pretende-se por meio desta, trazer um breve resgate histórico da Orientação Educacional e a atuação desse profissional da educação na atualidade, bem como o seu papel na construção do Projeto Político Pedagógico, tendo em vista que o Orientador Educacional tem a função de articulador junto à comunidade escolar, colaborando para que ocorra a participação de todos os envolvidos no processo educativo na construção coletiva e democrática do projeto da escola.
Effects of interactions between macroalgae and seagrass on the distribution of macrobenthic invertebrate communities at the Yellow River Estuary, China
Authors: Wang Xinyan , Yan Jiaguo , Bai Junhong , Shao Dongdong , Cui Baoshan
Published: March 2021

Algae-dominance in seagrass beds has been well recognized, however, the competitive relationship between seagrass and macroalgae along land-sea gradients and their ecological effects has received little attention. In this study, a field survey was conducted at the Yellow River Estuary to investigate the effects of macroalgal proliferation on seagrass and macrobenthic invertebrate communities. Our results suggested that strong competitive interaction existed between the two primary producers, and the positive or negative effects of macroalgae on seagrass growth varied along land-sea gradient. Furthermore, the dominant controlling factors on the biomass, density and diversity of macrobenthic invertebrate communities were found to vary accordingly, i.e., from features of the primary producers in the nearshore where macroalgae suppressed seagrass growth to hydrodynamic disturbance in the offshore where macroalgae facilitated seagrass growth. Our study emphasizes the importance to integrate interspecific competition into ecosystem-based management of seagrass ecosystem, and provides references for additional ecological indicators.
Crust formation on sandy savanna cropland soils and their potential to reduce dust emissions
Authors: Vos Heleen , Fister Wolfgang , Eckardt Frank , Palmer Anthony , Kuhn Nikolaus
Published: March 2021

After the conversion to cropland, dust emissions can lead to the degradation of agricultural soil. There are also offsite effects of dust emission due to the impact of dust on climate, human health, and global biogeochemistry. The sandy croplands in the Free State of South Africa have been identified by Eckardt et al. (2020) as one of the main dust sources in South Africa. The Free State is a semi-arid province that is dominated by grassland plains and 31% of the land is utilized for agriculture. The emission of dust from sandy Luvisols and Arenosols, which are typically used for crop farming, is mainly controlled by the cropping cycle. In general, the fields are left bare from at least July until December. When the fields have low surface roughness and stubble cover, the presence of physical soil crusts could be one of the main factors protecting the surface against wind erosion. Crusts can form before or during the growing season, before the vegetation cover is too extensive and protects the soil from raindrop impact. The aim of this study was to investigate the occurrence and strength of physical soil crusts on cropland soils in the Free State, to identify the rainfall required to form a stable crust, and to test their impact on dust emissions. Crust strength was measured using a fall cone penetrometer and a torvane, while laboratory rainfall simulations were used to form experimental crusts. Dust emissions from non-crusted and crusted soils were measured and compared with a Portable In-Situ Wind Erosion Laboratory (PI-SWERL).

Our results show that crusts with sufficient strength to limit dust emissions form on bare Arenosols and Luvisols in the field, illustrating their potential impact on dust emissions. The laboratory rainfall simulations showed that stable crusts could be formed on these soils by 15 mm of rainfall, which is a common amount for single events during the rainy season in the Free State. The PI-SWERL experiments illustrated that the PM10 emission flux of such crusted soils is between 0.14% and 0.26% of that of a non-crusted Luvisol and Arenosol, respectively. The presence of loose sand on the crust acts as an abrader and can increase the emissions up to 4% and 8 % of the non-crusted dust flux. Overall, our study shows that crusts in the field are potentially strong enough to protect the soil surfaces against wind erosion during a phase of the cropping cycle when the soil surface in not protected by plants. These conclusions are not limited to the converted grasslands in the Free State. This indicates that applying farming techniques on croplands that protect crusts or enhance crust formation could be considered as soil management approach to minimize dust emission from dryland sandy soils.
Flood simulation errors show an unexpected seasonal trend: results obtained on a set of 229 catchments and 11,054 flood events
Authors: Astagneau Paul C. , Bourgin François , Andréassian Vazken , Perrin Charles
Published: March 2021

To improve the predictive capability of a model, one must identify situations where it fails to provide satisfactory results. We tried to identify the deficiencies of a lumped rainfall-runoff model used for flood simulation (the hourly GR5H-I model) by evaluating it over a large set of 229 French catchments and 11,054 flood events. Evaluating model simulations separately for individual flood events allowed us identifying a seasonal trend: while the model yielded good performance in terms of aggregated statistics, grouping results by season showed clear underestimations of most of the floods occurring in summer. The largest underestimations of flood volumes were identified when high-intensity precipitation events occurred and when the precipitation field was highly spatially variable. Low antecedent soil moisture conditions were also found to be strongly correlated with model bias. Overall, this study pinpoints the need to better account for short-duration processes to improve the GR5H-I model for flood simulation.
From static alteration to mylonitization: a nano- to micrometric study of chloritization in granitoids with implications for equilibrium and fluid percolation length scales
Authors: Airaghi Laura , Dubacq Benoit , Verlaguet Anne , Bourdelle Franck , Bellahsen Nicolas , Gloter Alexandre
Published: March 2021

Strain accommodation in upper crustal rocks is often accompanied by fluid-mediated crystallization of phyllosilicates, which influence rock strength and shear zone formation. The composition of these phyllosilicates is commonly used for pressure-temperature-time constraints of deformation events, although it is often highly heterogeneous. This study investigates the reactions producing a phyllosilicate, chlorite, in and below greenschist-facies conditions and the variations in chlorite composition, along a strain gradient in the Bielsa granitoid (Axial Zone, Pyrenees). Compositional maps of chlorite (including iron speciation) are compared to nanostructures observed by transmission electron microscopy in increasingly-strained samples and related to mechanisms of fluid percolation and scales of compositional homogenisation. In the Bielsa granitoid, altered at the late Variscan, Alpine-age shear zones are found with high strain gradients. The undeformed granitoid exhibits local equilibria, pseudomorphic replacement and high compositional heterogeneities in chlorite. This is attributed to: (i) variable element supply and reaction mechanisms observed at nanoscale and (ii) little interconnected intra- and inter-grain nanoporosity causing isolation of fluid evolving in local reservoirs. In samples with discrete and mm-sized fractures, channelized fluid triggered the precipitation of homogeneous Alpine chlorite in fractures, preserving late-Variscan chlorite within the matrix. In low-grade mylonites, where brittle-ductile deformation is observed, micro-, nano-cracks and defects allows the fluid percolating into the matrix at the scale of hundreds of µm. This results in a more pervasive replacement of late-Variscan chlorite by Alpine chlorite. Local equilibria and high compositional heterogeneities in phyllosilicates as chlorite are therefore preserved according (i) matrix-fracture porosity contrasts at nanoscale and (ii) the location and interconnection of nanoporosity between crystallites of phyllosilicates that control reaction mechanisms and element mobility. In low grade mylonites, mineral and compositional replacement remains incomplete despite the high strain.
Spatio-temporal development of large scale auroral electrojet currents relative to substorm onsets
Authors: Käki Sebastian , Viljanen Ari , Juusola Liisa , Kauristie Kirsti
Published: March 2021

The electric currents flowing in the ionosphere change rapidly and a large amount of energy is dissipated in the auroral ionosphere during auroral substorms. An important part of the auroral current system are the auroral electrojets whose profiles can be estimated from magnetic field measurements from low Earth orbit satellites. We have combined electrojet data derived from the Swarm satellite mission of ESA with the substorm database derived from the SuperMAG ground network data. We organize the electrojet data in relation to the location of the onset and obtain statistics for the development of the integrated current and latitudinal location for the auroral electrojets relative to the onset. Especially we show that just after the onset the latitudinal location of the maximum of the westward electrojet determined from Swarm satellite data is mostly located close to the onset latitude in the local time sector of the onset regardless of where the onset happens.
Solar wind structures and their effects on energetic electron precipitation
Authors: Salice Josephine Alessandra , Tyssøy Hilde Nesse , Smith-Johnsen Christine , Babu Eldho Midhun
Published: March 2021

Energetic electron precipitation (EEP) into the Earth's atmosphere can collide with gases and deposit their energy there. The collisions between electrons and atmospheric gasses initiate several chemical reactions which can reduce the ozone concentration. Ozone is critically important in the middle atmosphere energy budget as changes in the ozone concentration impact temperature and winds. EEP is not fully understood in terms of how much energy is being deposited and what the associated drivers are. An accurate quantification of EEP has limitations due to instrumental challenges and therefore imposes limitations of the associated EEP parameterization into climate models. A solution to this problem is a better understanding of the driver processes of energetic electron acceleration and precipitation, alongside optimized data handling. In this study the bounce loss cone fluxes are inferred from EEP measurements by the Medium Energy Proton and Electron Detector (MEPED) on board the Polar Orbiting Environmental Satellite (POES) and the Meteorological Operational Satellite Program of Europe (METOP) at tens of keV to relativistic energies. It investigates EEP in contexts of different solar wind structures: high-speed solar wind streams (HSSs) and coronal mass ejections (CMEs), during an eleven-year period from 2004 – 2014. While today's chemistry climate models only provide snapshots of EEP, independent of context, this study aims to understand the context EEP is created in, which will allow a more accurate estimate of the EEP to be applied in atmospheric climate models.
Sensitivity study of PBL schemes and urban morphology parameters using the WRF-BEP+BEM model over a Mediterranean coastal city
Authors: Segura Ricard , Gilabert Joan , Ventura Sergi , Badia Alba , Martilli Alberto , Villalba Gara
Published: March 2021

Cities house over 50% of the population, despite covering only 2% of the earth’s surface area. With the increased urbanization, the impact of climate change in urban areas is seen as a major problem. In the case of the Mediterranean region, the increase in frequency, intensity and duration of extreme heat wave events supposes a significant risk for the population. These factors have raised the focus on understanding and modelling the impact of extreme heat events on cities and to improve the simulation of these events to investigate possible heat adaptation/mitigation measures to ameliorate urban temperatures. This study investigates the sensitivity of high-resolution mesoscale simulations of the Metropolitan Area of Barcelona (AMB) to different urban physical parametrizations for a heat wave event in order to improve urban atmospheric modelling of Mediterranean coastal cities and to reduce uncertainties. The simulations are conducted using the WRF model coupled to the Building Effect Parameterization and the Building Energy Model (BEP+BEM) at 1 km resolution. The physical aspects in WRF that are analysed are: 1) the refinement of urban morphological parameters; and 2) planetary boundary layer (PBL) scheme. The results show that the inclusion of more specific urban morphology does not suppose a better performance of the WRF simulation in comparison to the use of 11 urban land-use classes with averaged urban morphological parameters, although it reduces systematic errors on night-time near-surface temperatures, especially in urban green areas. The comparison between PBL schemes shows that this aspect has a significative influence in the simulation of potential temperature inside the PBL and on near-surface temperature and wind. Moreover, the impact of urbanization on the urban boundary layer (UBL) is determined for the AMB simulating a scenario with no urbanization inside the AMB (all urban areas are changed to croplands). Results show that urbanization not only changes near-surface temperatures, but it has a considerable reducing impact on sea and land-breezes, and an intensifying effect on the PBL height.
 Water-Energy-Food Nexus assessment of the intended outcomes of the Songwe River Basin Programme in Malawi and Tanzania
Authors: Masia Sara , Kiala Zolo , Sušnik Janez , Mabhaudhi Tafadzwanashe , Jewitt Graham
Published: March 2021

Water, Energy, and Food sectors are interconnected and part of a complex system referred to as the Water-Energy-Food (WEF) nexus. The assessment of WEF interactions through the nexus approach is crucial to illustrate interlinkages, synergies, and minimise trade-offs among these three components when development plans are assessed. Water, energy, and food are at the core of developing countries' goals and strategies where interest in the WEF nexus approach is rapidly growing. However, a lack of empirical evidence, appropriate methods, and quantitative WEF nexus assessment tools has been highlighted. Thus, WEF Nexus Toolkit (WEF-Tools) project aims at supporting policymakers across the water, energy, and food sectors to make evidence-based decisions on environmental, economic, and resource security issues. In this study, we qualitatively and quantitatively assess the WEF nexus in the Songwe River Basin (SRB), located on the border between Malawi and Tanzania. Reducing poverty, improving human health and livelihoods, ensuring water, food, and energy security, mitigating floods, and enhancing sustainable river basin management are the main challenges recognised by the SRB Programme (SRBP) jointly developed by the Governments of both countries. The construction of a multi-purpose dam is a key objective of the SRBP. The dam is intended to supply water for ⁓180 MW hydropower plant, ⁓86000 dwellers, ⁓3000 ha of irrigation schemes in each country, and control floods in the lower part of the basin. WEF-Tools has assessed the SRBP expected outcomes by applying an approach that starts from conceptual mapping of the SRB nexus system and progresses to the development of quantitative tools such as System Dynamics Models (SDMs), and identification of suitable indicators for the assessment of different scenarios, management strategies, subsequently providing decision-makers with feasible development pathways. Ultimately, this work will provide a structured knowledge base, simulation tool, dashboard, and a composite nexus index co-developed, tested, validated, and refined through interactive collaboration with stakeholders and local experts. Thus, it is intended that the toolkit supports the development of short-, medium- and long-term strategies for sustainable integrated resource management and policy development. Outcomes will provide a means for government ministries, NGOs, and development agencies to assess progress towards relevant Sustainable Development Goals (SDGs), particularly SDGs 2, 6, and 7.

 

Keywords: Water-Energy-Food Nexus, multi-purpose reservoir, decision making, System Dynamics Model, SDGs, Songwe River Basin

 

 
Slip bursts during coalescence of slow slip events in Cascadia
Authors: Bletery Quentin , Nocquet Jean-Mathieu
Published: March 2021

Both laboratory experiments and dynamic simulations suggest that earthquakes can be preceded by a precursory phase of slow slip. Observing processes leading to an acceleration or spreading of slow slip along faults is therefore key to understand the dynamics potentially leading to seismic ruptures. Here, we use continuous GPS measurements of the ground displacement to image the daily slip along the fault beneath Vancouver Island during a slow slip event in 2013. We image the coalescence of three originally distinct slow slip fronts merging together. We show that during coalescence phases lasting for 2 to 5 days, the rate of energy (moment) release significantly increases. This observation supports the view proposed by theoretical and experimental studies that the coalescence of slow slip fronts is a possible mechanism for initiating earthquakes.
Disturbances in coarse bedload transport in a formerly glaciated catchment
Authors: Płaczkowska Eliza , Krzemień Kazimierz , Gorczyca Elżbieta , Bojarczuk Anna , Żelazny Mirosław
Published: March 2021

Dynamics of bedload transport increases with an increase of hydrologic parameters, i.e. stream power, water velocity and discharge. In mountain stream channels, these parameters increase in the downstream direction, and therefore the dynamics of bedload transport increase down the channel. This pattern may become altered temporarily or over long periods of time due to local extreme events or human impact. Here, we identify disturbances in bedload transport in the formerly glaciated catchment located in the Western Tatras in Poland. We then determine the role of disturbances in system connectivity and sediment transfer. Bedload transport measurements in the Chochołowski catchment were performed in the period 1975 to 2018. The said process occurred as many as triggered up to several times a year. However bedload became activated along the entire length of the channel system (10.5 km) every 2 to 5 years when the stream discharge exceeded 10 m3 s-1. The distance of bedload movement during such events was between 12 m in headwaters and over 100 m in the lower reach. In such situations, bedload dynamics increased downstream, and stream power was sufficient to overcome local barriers (i.e. boulder and log steps). Downstream increases in bedload dynamics was disturbed and inverted by sudden snowmelt and locally heavy rainfall. These types of events caused the dynamics of bedload transport to be up to 320% greater in the upper part of the studied catchment and to decline in the downstream direction over a distance of 7 km to yield an attenuation effect. The same pattern was observed in local tributaries where the dynamics of bedload transport were 200% higher in the upper part and attenuation was observed along a distance of 1.5 km in the downstream direction. All events of this type cause seasonal disturbances in bedload transport. However, the greatest effect on bedload dynamics was produced by natural deforestation. A 16% decrease in forest cover causes a fluvial system disequilibrium manifested in an intensification of hydro-geomorphologic processes and formation of new landforms.
Modeling differentiation in igneous systems: On the importance of considering temperature & composition dependent partition coefficients
Authors: Toussaint Aurore , France Lydéric
Published: March 2021

       Studying magma reservoir processes is one of the keys to understand the evolution of igneous systems. One of the main processes, magma differentiation, governs the thermal evolution and chemical composition of the melt-crystal assemblage (magma or mush depending on the relative proportions), and therefore exerts a first order control over its physical properties (density, viscosity), and thus on reservoir dynamics. Various approaches have been implemented to model differentiation in an attempt to benchmark all the involved variables like initial and phase compositions, temperature, pressure, and oxygen fugacity (C0, X, T, P, fO2). Those approaches are among others mass balance calculations considering partition coefficients (D) values, experimental studies, thermodynamic models or a combination of those. In any of those cases, the evolution of trace elements is governed by the value of the D that is known to be dependent on (P, T, X, fO2). However, most of the present-day studies still use fixed values of D to provide first order estimates.

      Here, we present an approach combining thermodynamic modeling (relying on Rhyolite-MELTS, Gualda et al., 2012), that integrates X-T-P-fO2-dependent D for Rare Earth Elements (REE). We applied this new approach to a MORB system, with olivine, clinopyroxene and plagioclase as main mineral phases, and compared results to more classical approaches. D are derived from the models of Sun & Liang (2012, 2013, 2014) and Sun et al. (2017). The resulting model highlights that T & X effects on the D values can add or counterbalance each other depending on the mineral considered. In any cases our results emphasize the gain of using thermodynamic models along with both T- & X-dependent D values to properly model the evolution of igneous systems. Relying on our results, and on the corresponding thermodynamics constraints, we were also able to provide D for any mineral composition crystallized from this MORB system. Results bring to light that an error of ~1 order of magnitude of the Dmineral-melt value could be introduced when considering a fixed value of D.

 

Gualda et al. (2012) Journal of Petrology, 53-5, 875-890; Sun & Liang (2012) Contrib Mineral Petrol 163-5: 807-823; (2013) Chem Geol 358: 23-36; (2014) Chem Geol 372: 80-91; Sun et al. (2017) Geochim Cosmochim Acta 206: 273-295.

 
Geoscience Authors and Reviewers during the COVID-19 Pandemic: Demographic Analysis of AGU's Authors and Peer Reviewers
Authors: Wooden Paige , Hanson Brooks
Published: March 2021

The COVID-19 pandemic has changed the way we work and live, and as of January 2020, the increase in cases and the initiation of the vaccine introduces even more uncertainty into the short-term future. With an increase in domestic responsibilities for many people, there is a heighted concern about the productivity of the Earth and space science research community, and especially the impact on student, early career researchers, and women. AGU's rich data has allowed us to investigate how the pandemic has affected our constituents, and in a poster presented at AGU 2020, we showed that submissions increased in 2020 with the same proportion of women submitting in 2020 and little monthly variation. Submissions from men and women in their 20s decreased in 2020 compared to 2019, while submissions from women in their 30s and 50s and men in their 40s increased.  We saw minor monthly fluctuations in submissions by the country-region of submitting author, with an increase in total and proportional submissions from China continuing from 2019. Additionally, our editors were concerned about the time the most affected scientists could devote to research and peer reviewing. This analysis seeks to update demographics of submitting authors with Q1 2021 data and introduce an analysis of the effect the pandemic had on our article peer reviewers. Preliminary analysis shows very little difference in the invite rates of women in 2020 compared to 2019 (+1%), and only a 0.4% decrease in women's accept to review rates in 2020 compared to 2019. We also only see slight monthly fluctuations in invite and review accept rates. Invitations to review by country of reviewer are proportionally similar in 2020 to those in 2019. This analysis will also investigate any changes in invited and agreed reviewer age to see how the pandemic may have influenced those likely to have research, teaching, and family commitments.
Determining latitudinal extent of energetic electron precipitation  using MEPED on-board NOAA POES
Authors: Babu Eldho Midhun , Tyssøy Hilde Nesse , Smith-Johnsen Christine , Maliniemi Ville , Salice Josephine Alessandra , Millan Robyn
Published: March 2021

Energetic electron precipitation (EEP) from the plasma sheet and the radiation belts, can collide with gases in the atmosphere and deposit their energy. EEP increase the production of NOx and HOx, which will catalytically destroy stratospheric ozone, an important element of atmospheric dynamics. Therefore, measurement of latitudinal extent of the precipitation boundaries is important in quantifying atmospheric effects of Sun-Earth interaction and threats to spacecrafts and astronauts in the Earth's radiation belt.
This study uses measurements by MEPED detectors of six NOAA/POES and EUMETSAT/METOP satellites from 2004 to 2014 to determine the latitudinal boundaries of EEP and its variability with geomagnetic activity and solar wind drivers. Variation of the boundaries with respect to different particle energies and magnetic local time is studied. Regression analyses are applied to determine the best predictor variable based on solar wind parameters and geomagnetic indices. The result will be a key element for constructing a model of EEP variability to be applied in atmosphere climate models.
Thermodynamic constraints on assimilation of silicic crust by primitive magmas
Authors: Heinonen Jussi S , Spera Frank J , Bohrson Wendy A
Published: March 2021

Some studies on basaltic and more primitive rocks suggest that their parental magmas have assimilated more than 50 wt.% (relative to the initial uncontaminated magma) of crustal silicate wallrock. But what are the thermodynamic limits for assimilation by primitive magmas? This question has been considered for over a century, first by N.L. Bowen and many others since then. Here we pursue this question quantitatively using a freely available thermodynamic tool for phase equilibria modeling of open magmatic systems — the Magma Chamber Simulator (MCS; https://mcs.geol.ucsb.edu).

In the models, komatiitic, picritic, and basaltic magmas of various ages and from different tectonic settings assimilate progressive partial melts of average lower, middle, and upper crust. In order to pursue the maximum limits of assimilation constrained by phase equilibria and energetics, the mass of wallrock in the simulations was set at twice that of the initially pristine primitive magmas. In addition, the initial temperature of wallrock was set close to its solidus at a given pressure. Such conditions would approximate a rift setting with tabular chambers and high magma input causing concomitant crustal heating and steep geotherms.

Our results indicate that it is difficult for any primitive magma to assimilate more than 20−30 wt.% of upper crust before evolving to intermediate/felsic compositions. However, if assimilant is lower crust, typical komatiitic magmas can assimilate more than their own weight (range of 59−102 wt.%) and retain a basaltic composition. Even picritic magmas, more relevant to modern intraplate settings, have a thermodynamic potential to assimilate 28−49 wt.% of lower crust before evolving into intermediate/felsic compositions.

These findings have important implications for petrogenesis of magmas. The parental melt composition and the assimilant heavily influence both how much assimilation is energetically possible in primitive magmas and the final magma composition. The fact that primitive mantle melts have potential to partially melt and assimilate significant fractions of (lower) crust may have fundamental importance for how trans-Moho magmatic systems evolve and how crustal growth is accomplished. Examples include generation of siliceous high-magnesium basalts in the Precambrian and anorogenic anorthosite-mangerite-charnockite-granite complexes with geochemical evidence of considerable geochemical overprint from (lower) crustal sources.
The IAGOS Research Infrastructure for monitoring atmospheric composition and air quality using commercial aircraft
Authors: Clark Hannah , Team Iagos
Published: March 2021

IAGOS (In-service Aircraft for a Global Observing System) is a European Research Infrastructure for global observations of atmospheric composition using commercial aircraft. Commercial aircraft are ideal platforms for providing long-term in-situ measurements with high vertical and temporal resolution, particularly at cruise altitude (between 9 and 13 km) in the climate-sensitive region of the atmosphere known as the upper troposphere-lower stratosphere (UTLS). IAGOS also provides landing and take-off profiles at almost 300 airports throughout the world which are of major interest for air quality issues. Fully automated instruments are permanently installed on Airbus A330 aircraft operated by different airlines. Data are collected on about 500 flights per aircraft per year. All the aircraft measure the abundances of many essential climate variables, chiefly ozone and the precursor carbon monoxide, water vapour, clouds and meteorological parameters. Additional instruments can be installed to measure nitrogen oxides, aerosols, or the greenhouse gases carbon dioxide and methane. The data are transmitted in near to real real time to weather services and are freely available for the scientific community, national air quality prediction centres and the Copernicus Atmosphere Monitoring Service (CAMS). We describe the importance of these measurements in the monitoring of global atmospheric composition and air quality. In particular, we show examples from the Copernicus Atmosphere Monitoring Service (CAMS) where IAGOS data are used in the evaluation and improvement of forecasts of air quality over Europe, and discuss how the development of the IAGOS data transmission and instrumentation may fertilize infrastructure development for other airborne platforms.
Validations of Three Global Gravity Field Models Using the QDaedalus System Observed Astrogeodetic Vertical Deflections in the Munich Region, Germany
Authors: Albayrak Muge , Hirt Christian , Guillaume Sébastien , Shum Ck , Bevis Michael , Zeray Öztürk Emel , Bildirici Ibrahim Öztug
Published: March 2021

The total station-based QDaedalus system, developed in 2014 by ETH Zurich in Switzerland, incorporates a charge-coupled device (CCD) camera in support of daytime geodetic and nighttime astrogeodetic observations. The successful realization of astrogeodetic observations has resulted in astrogeodetic vertical deflection (VD) data collection in Germany, Italy, Hungary, Australia, and Turkey. Astrogeodetic observations carried out in Munich, Germany were used to determine the precision and accuracy of the newly installed QDaedalus system, which was found to be ~0.2 arcseconds for both the North-South (N-S) and East-West (E-W) VD components. In this study, 10 benchmark observations in the Munich region were also used to assess the quality of three global gravity field models—Global Gravitation Model Plus (GGMplus), Earth Residual Terrain Modelled 2160 (ERTM2160) and Earth Gravitational Model 2008 (EGM2008)—through comparison with the QDaedalus observations. The results of these comparisons between the predicted and observed VD data are: (i) The GGMplus predicted VD values were found to be closer to the observed VDs, with the differences for both the N-S and E-W VD components being ~0.2″, and reaching a maximum of 0.3″ and 0.4″ for the N-S and E-W components, respectively; (ii) The ERTM2160 predicted values were also found to be closer to the observed VDs, with differences of 0.4″ or less for the N-S component, with the exception of one benchmark (BM 8), and 0.2″ or less for the E-W component, with the exception of one benchmark (BM 9); and, (iii) When the predicted VDs computed using EGM2008 were analysed, we found that they were less accurate than the predicted GGMplus and ERTM2160 values. Therefore, the maximum differences between the observed and EGM2008 predicted VD data were for 0.9″ N-S and 1.8″ for E-W. Finally, we conclude with a comparison of the results of this Munich Region study with the results of a prior QDaedalus study, which was conducted in Istanbul (Albayrak et al. 2020), to assess the accuracy of the EGM2008 and GGMplus models.

 

Albayrak, M., Hirt, C., Guillaume, S., Halicioglu, K., Özlüdemir, M.T., Shum, C.K., 2020. Quality assessment of global gravity field models in coastal zones: a case study using astrogeodetic vertical deflections in Istanbul, Turkey, Studia Geophysica et Geodaetica, 64(3), 306–329. doi: 10.1007/s11200-019-0591-2
Homotopy Particle Filter and Data Assimilation
Authors: Restrepo Juan , Ramirez Jorge
Published: March 2021

A homotopy schedule is proposed, wherein from a known probability distribution the normalization constant for an improper probability density function can be found. An improper distribution is one for which the normalization is not known, but its functional form is. In the statistical mechanics constant this amounts to finding the canonical ensemble for the improper distribution. Along the way, the method will generate samples from the target distribution.

This homotopy schedule can be adopted to particle filters used for Bayesian estimation with the aim of improving estimates of the mean path and the uncertainty of a noisy dynamical system, for which noisy observations are available. The method is useful when the dynamics are highly nonlinear, especially if the observations that inform the likelihood have low uncertainty. In the context of data assimilation we require that the stochastic dynamics of the system have an asymptotic stationary distribution, which we use as a the known distribution in the homotopy procedure.

In this talk we present the methodology, apply it to the estimation of canonical ensembles and present numerical comparisons of the standard particle filter estimates with those of the homotopy data assimilation. 

 
Early detection of the flash drought: a preliminary study by the National Water Model
Authors: xu Li
Published: March 2021

As one key innovation in the NOAA hydrological modeling, the National Water Model (NWM) was recently upgraded to v2.0 in June 2019. The NWM could provide not only the streamflow prediction for hydrological guidance, but also the real-time high-resolution land state analysis and assimilation.  Based on the NWM v2.0 retrospective analysis from 1993 to 2018, we evaluated NWM soil moisture (SM) and evapotranspiration(ET) for the drought monitor application.  The Soil Moisture Percentile (SMP) from NWM is compared with the official US drought monitor (USDM) map in major drought events. The drought categories (D0-D4) based on NWM, is quantitively compared with similar drought monitor from the NLDAS2 multi-model ensemble.  A long time-series soil moisture monitor from CPC leaky bucket model is also compared against NWM, to distinguish the importance of the long temporal record vs high spatial resolution for drought monitor. The rapid intensification or rapid onset drought, i.e. flush drought, is also investigated by the temporal change of the SMP. The preliminary results indicated the NWM could well capture the major droughts during 2000 to 2018. In particular, the flash droughts indicated by the NWM could provide one to three weeks early warning than the USDM map, show great potential in the future application for flash drought detection, monitor and prediction.

 
Global-scale changes in Earth’s energy budget and implications for the water cycle
Authors: Allan Richard , Liu Chunlei
Published: March 2021

The climate system is heating up, causing warming at the surface and changes in the global water cycle. Updated reconstructions of Earth’s energy budget since the 1980s are presented and show how heat uptake is unevenly distributed across the northern and southern hemisphere. Heating is closely associated with ocean heat content changes and sea level rise while surface warming depends on partitioning between the upper mixed layer and deeper levels, leading to decadal variability. CMIP6 simulations are used to illustrate how global precipitation and evaporation are constrained by the Earth's energy balance to increase at ∼2–3%/°C and how this rate of increase is suppressed by rapid atmospheric adjustments in response to greenhouse gases and absorbing aerosols that directly alter the atmospheric energy budget. Rapid adjustments to forcings, cooling effects from scattering aerosol, and observational uncertainty can explain why observed global precipitation responses are currently difficult to detect but are expected to emerge and accelerate as warming increases and aerosol forcing diminishes.
EMPHASIS: European infrastructure for multi-scale plant phenotyping and simulation for food security in a changing climate
Authors: Pieruschka Roland , Fahrner Sven , Schurr Ulrich
Published: March 2021

Quantitative analysis of structure and function of plants has become the major bottleneck in basic plant research and applied use of plants in breeding or agricultural management. This is particularly important for sustainable intensification of crop production to ensure the amount and quality of plant biomass for human nutrition and industry in times of climate change. In recent years, significant interdisciplinary approaches have been started to establish plant phenotyping infrastructure with non-invasive methods that allow to quickly and non-invasively assessing the condition and properties of plants in the laboratory, greenhouse or field, make these data accessible through data and computational services and allow data reuse for meta-analysis or modelling.

In this presentation, we will outline the recent developments to integrate plant phenotyping across scales from lab to field including common data management approaches. The ESFRI research infrastructure EMPHASIS is developing a pan European infrastructure based of the portfolio of existing national plant phenotyping centers. The goal is to: i) provide a instrumented facilities for user access for quantitative trait assessment, ii) link data acquisition with data management and modelling, iii) develop, evaluate and disseminate knowledge and novel technologies. We will showcase phenotyping of quantitative traits under controlled and specifically field conditions providing novel inside on plant environment interaction for example in dedicated free air CO2 enrichment facilities and illustrate the development of pan-European information system making these data reusable. Finally, we will introduce the latest activities of IPPN e.V. is a networking platform linking the plant phenotyping centers and enabling close interaction across the globe.
Exploring trends for the H SAF ASCAT root-zone soil moisture data records
Authors: Fairbairn David , de Rosnay Patricia , Weston Peter
Published: March 2021

Environmental (e.g. floods, droughts) and weather prediction systems rely on an accurate representation of soil moisture (SM). The EUMETSAT H SAF aims to provide high quality satellite-based hydrological products, including SM.
ECMWF is producing ASCAT root zone SM for H SAF. The production relies on an Extended Kalman filter to retrieve root zone SM from surface SM satellite data. A 10 km sampling reanalysis product (1992-2020) forced by ERA5 atmospheric fields (H141/H142) is produced for H SAF, which assimilates ERS/SCAT (1992-2006) and ASCAT-A/B/C (2007-2020) derived surface SM. The root-zone SM performance is validated using sparse in situ observations globally and generally demonstrates a positive and consistent correlation over the period. A negative trend in root-zone SM is found during summer and autumn months over much of Europe during the period (1992-2020). This is consistent with expected climate change impacts and is particularly alarming over the water-scarce Mediterranean region. The recent hot and dry summer of 2019 and dry spring of 2020 are well captured by negative root-zone SM anomalies. Plans for the future H SAF data record products will be presented, including the assimilation of high-resolution EPS-SCA-derived soil moisture data.
Evolution of the East Africa-Arabia plume head
Authors: Civiero Chiara , Lebedev Sergei , Celli Nicolas L.
Published: March 2021

Hot plumes rising from Earth’s deep mantle are thought to form broad plume heads beneath lithospheric plates. In continents, mantle plumes cause uplift, rifting and volcanism, often dispersed over surprisingly broad areas. Using seismic waveform tomography, we image a star-shaped, low-velocity anomaly centered at Afar and composed of three narrow branches: beneath East Africa, beneath the Gulf of Aden, and beneath the Red Sea and West Arabia, extending north to Levant. We interpret this anomaly as the seismic expression of interconnected corridors of hot, partially molten rock beneath the East Africa-Arabia region. The corridors underlie areas of uplift, rifting and volcanism and accommodate an integral, active plume head. Eruption ages and plate reconstructions indicate that it developed south-to-north, and tomography shows it being fed by three deep upwellings beneath Kenya, Afar and Levant. These results demonstrate the complex feedbacks between the continental-lithosphere heterogeneity and plume-head evolution. Star-shaped plume heads sprawling within thin-lithosphere valleys can account for the enigmatic dispersed volcanism in large igneous provinces and are likely to be a basic mechanism of plume-continent interaction.
Adiabatic Heat Flow in Mercury with a Fe-8.5wt%Si Core
Authors: Berrada Meryem , Secco Richard , Yong Wenjun
Published: March 2021

Recent theoretical studies have tried to constrain Mercury’s internal structure and composition using thermal evolution models. The presence of a thermally stratified layer of Fe-S at the top of an Fe-Si core has been suggested, which implies a sub-adiabatic heat flow on the core side of the CMB. In this work, the adiabatic heat flow at the top of the core was estimated using the electronic component of thermal conductivity (kel), a lower bound for thermal conductivity. Direct measurements of electrical resistivity (ρ) of Fe-8.5wt%Si at core conditions can be related to kel using the Wiedemann-Franz law. Measurements were carried out in a 3000 ton multi-anvil press using a 4-wire method. The integrity of the samples at high pressures and temperatures was confirmed with electron-microprobe analysis of quenched samples at various conditions. Unexpected behaviour at low temperatures between 6-8 GPa may indicate an undocumented phase transition. Measurements of ρ at melting seem to remain constant at 127 µΩ·cm from 10-24 GPa, on both the solid and liquid side of the melting boundary. The adiabatic heat flow at the core side of Mercury’s core-mantle boundary is estimated between 21.8-29.5 mWm-2, considerably higher than most models of an Fe-S or Fe-Si core yet similar to models of an Fe core. Comparing these results with thermal evolution models suggests that Mercury’s dynamo remained thermally driven up to 0.08-0.22 Gyr, at which point the core became sub-adiabatic and stimulated a change from dominant thermal convection to dominant chemical convection arising from the growth of an inner core. Simply considering the internal structure of Mercury, these results support the capture of Mercury into a 3:2 resonance orbit during the thermally driven era of the dynamo.
Maize yield forecast using earth observation data and machine learning for Sub-Saharan Africa
Authors: Lee Donghoon , Davenport Frank , Shukla Shraddhanand , Husak Greg , Funk Chris
Published: March 2021

In Sub-Saharan Africa, forecasting of agricultural production is becoming increasingly important for the management of the agricultural supply chain, market prediction, and food aid. More importantly, agricultural forecasts can enhance the ability of governments and humanitarian organizations to respond better to food production shocks and price spikes caused by extreme droughts. Here, we use earth observation (EO) and machine learning (ML) techniques to develop 1-6 months ahead end-of-season maize yield forecast models for several regions in Sub-Saharan Africa. We find that ML models present different aspects of forecast accuracy compared to baseline regression models. Specifically, we investigate 1) skillful EO predictors and their predictability in a given region and lead-time and 2) the benefits of using finer time resolution of EO data that can potentially capture temporal dynamics in early reproductive stages. Overall, this study provides the groundwork for an operational crop yield forecast and famine warning system. Actionable famine risk predictions can radically improve existing disaster management practices of aid organizations by providing advanced preparedness and response strategies.