bluuebunny/crossref_metadata_2025 huggingface dataset:
SAR Imaging Geodesy with Electronic Corner Reflectors (ECR) and Sentinel-1 – First Experiences
Authors: Oikonomidou Xanthi , Eineder Michael , Gisinger Christoph , Gruber Thomas , Heinze Markus , Sdralia Vasiliki
Published: March 2020

SAR imaging geodesy is a new technique in the field of geodesy and remote sensing that enables the 3D localization of specifically designed radar targets. The absolute 3D position of a radar target in the ITRF can be estimated by means of least squares adjustment, when combining at least two sets of radar coordinates extracted from SAR images and the corresponding orbital arcs given by precise orbit determination. The installation of permanent radar targets allows for long-term position monitoring, making the technique a particularly interesting candidate for displacement and height change observations. While the principle of geodetic positioning with SAR is well-established, the selection of the radar target suitable for an application is subject to discussion. Parameters to be considered are the resolution of the radar images which can be provided by satellites like Sentinel-1 or TerraSAR-X, the size of the radar target with respect to the image resolution, the required localization accuracy of the selected application, and possible environmental and/or technical limitations at the installation site. Two main categories of artificial radar targets can be identified: passive reflectors and active transponders. Examples of passive reflectors that have been tested at geodetic observatories are corner reflectors, octahedron reflectors and tophats, while an example of active transponders is the experimental Electronic Corner Reflector (ECR).

The poster illustrates the first results acquired from the testing of ECRs operating in C-band, and their 3D localization using the IW medium resolution products of Sentinel-1A and 1B. The operation principle, the installation and mounting options, and the use of the ECRs as a small and portable alternative to passive reflectors are additionally discussed.
From Mesozoic subduction to Cenozoic extension: what controlled the tectonic process of South China Sea?
Authors: Sun Zhen , Li Fucheng , Qiu Ning , Sun Longtao
Published: March 2020

The South China Sea (SCS) is one of the largest marginal seas in the western Pacific. Widespread onshore outcrops of the late Mesozoic granitic and volcanic rocks suggest that the SCS was once an active margin associated with Paleo-Pacific or proto South China Sea subducted toward South China in the late Mesozoic. It transitioned into rifting after late Cretaceous and then spreading in Oligocene. IODP drilling indicates that SCS transitioned from subduction into sea spreading in a short time (no more than 30 Myrs) and show diachronous breakup both temporally and spatially. What controlled this tectonic process? In order to answer these questions, we used a combination of data sources, including reprocessed magnetic data, drilling/dredging samples, depositional environment and deformation style on multi-channel seismic profiles to constrain the possible spatial distribution of the Mesozoic volcanic arc first and found that the southwest part of the Mesozoic volcanic arc distributes on both sides of the southwest SCS sub-basin, while the northeast part remains nearly in its original location. The results suggest that the initial breakup sites for the SCS margin might be arc area in the southwest and fore-arc area in the northeast during the opening of SCS basin. Mathematical modeling experiments suggest that several circumstances may cause fore-arc breakup, including: steepening of the subducting plate, a pre-existing rheologically/tectonically weak zone in the arc-front/fore-arc in the subduction plate, seamount or plateau subduction and damaging of the fore-arc area. Also if the subducting slab is young or the subduction time is short, fore-arc breakup will occur. Further analysis suggested that along with the rifting, two sources of magma may have contributed to the rifting. One is supposed to be decompressive melting, the other one is deep sourced and constitute the high velocity lower crustal magmatic underplating, which is supposed to be related with the subduction slab break off.
Heatwaves over Europe: Identification and connection to large-scale circulation
Authors: Rouges Emmanuel , Ferranti Laura , Kantz Holger , Pappenberger Florian
Published: March 2020

                Heat waves have important impacts on society and our environment. In Europe for instance, the summer of 2003 caused upwards of 40000 fatalities. They also impact the crop production, ecosystems, and infrastructures. In a warming climate, heat wave intensity and frequency are likely to increase with potentially more dramatic consequences.

                Considering this, it is crucial to forecast such extreme events and therefore gain a better understanding of their triggering processes. The determination of these processes requires to identify heat wave patterns (timing and location) together with the correlated large-scale circulation patterns. This will enable to devise early warning systems, that could help mitigate the impact.

                This work is part of an ongoing PhD project focusing on improving the forecast of heat waves at sub-seasonal time scale. The main objectives are to evaluate the link between large scale weather patterns and severe warm events over Europe and measure current level of predictive skill. The first part will focus on defining an objective criteria to identify heat wave events in the ERA5 reanalaysis dataset from ECMWF. The identification of heat waves depends on three main criteria: temperature threshold, spatial and temporal extension. Meaning that the temperature should exceed a defined threshold over a large enough region and for a long enough period. We will consider daily means as well as maximum and minimum values of 2m temperature. We will identify the circulation patterns (persistent high pressure systems) associated with heat wave events and analyse the key differences with persistent high pressure systems that are not associated with heat waves.

                This work is part of the Climate Advanced Forecasting of sub-seasonal Extremes (CAFE) project, funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grand agreement No 813844.
The story of Skeptical Science: How citizen science helped to turn a website into a go-to resource for climate science
Authors: Winkler Bärbel , Cook John
Published: March 2020

Skeptical Science (SkS) is a website with international reach founded by John Cook in 2007. The main purpose of SkS is to debunk misconceptions and misinformation about human-caused climate change and features a database that currently has more than 200 rebuttals based on peer-reviewed literature. Over the years, SkS has evolved from a one-person operation to a team project with science-minded volunteers from around the globe. The Skeptical Science team also actively contribute to published research, with a highlight being the often cited 97% consensus paper published in 2013 (Cook et al. 2013) for which team members content-analysed about 12,000 abstracts in a study whose publication fee was crowd-funded by readers of the website.

The SkS author community formed in 2010 in response to the proposal to expand existing rebuttals to three levels: basic, intermediate, and advanced. Since then, team members regularly collaborate to write and review rebuttal and blog articles for the website. Volunteer translators from many countries have translated selected content into more than 20 languages including booklets such as The Debunking Handbook, The Uncertainty Handbook or The Consensus Handbook. In addition to the already mentioned consensus study, team members have helped with other research projects initiated by John Cook such as the efforts to train a computer to detect and classify climate change misinformation. Another significant project is the Massive Open Online Course (or MOOC) “Denial101x: Making Sense of Climate Science Denial” in collaboration with the University of Queensland, for which the SkS team produced numerous video lectures and for which forum moderators were recruited. Outreach activities such as the “97 Hours of Consensus” were crowdsourced with team members collecting and organising content and providing technical support.

Challenges: Due to the volunteer nature of people’s involvement, there are some challenges involved as not everybody is available to help with tasks all the time. People help as much – or as little – as their time allows and there’s always some turn-over with new people joining while others leave.

Skeptical Science (SkS): (accessed November 29, 2019)

Cook, J., Nuccitelli, D., Green, S. A., Richardson, M., Winkler, B., Painting, R., Way, R., Jacobs, P., & Skuce, A. (2013). . Environmental Research Letters, 8(2), 024024+.

Cook, J., Schuennemann, K., Nuccitelli, D., Jacobs, P., Cowtan, K., Green, S., Way, R., Richardson, M., Cawley, G., Mandia, S., Skuce, A., & Bedford, D. (April 2015). Denial101x: Making Sense of Climate Science Denial. edX.

Cook, J., & Lewandowsky, S. (2011). . St. Lucia, Australia: University of Queensland. ISBN 978-0-646-56812-6.
Early Cretaceous (Aptian) provenance and tectonic response in Songliao Basin, NE China: Evidence from detrital zircon U-Pb ages from the Shahezi Formation
Authors: An Dongzhao
Published: March 2020

In Early Cretaceous, Shahezi Formation developed in syn-rift stage which belongs to the deep strata of the Songliao Basin, China. Due to the poor outcrop development, there is no previous study or report on the provenance of detrital zircons from Shahezi Formation before. The Songke 2 well is a part of Songliao Basin drilling project which belongs to the International Continental Scientific Drilling Projects (ICDP). The conduct of this scientific drilling is to obtain a nearly complete Cretaceous terrestrial sedimentary record, as determined from basin-filling history. Therefore, this research will focus on the sample from Songke 2 well. This study based on continuous and complete sampling which are unique research materials. What’s more, Songliao Basin is one of the largest continental sedimentary basins in the world, which holds the most important reserves of Chinese oil and natural gas. Consequently, this study is a kind of significance for oil and natural gas prospects of deep strata in Songliao Basin.

Through the detailed description about cores, fan delta facies and lacustrine facies can be identified in this study. Also, the detailed information and sedimentary environment at Early Cretaceous can be clarified. The upper member of Shahezi formation shows the characteristics of fan delta facies intersecting shore-shallow lakes, reflecting the multistage cyclicity changes under the sufficient source supply during the syn-rift stage. In order to define the provenance of the upper member of Shahezi Formation in the north-central area of the Songliao Basin, five sandstone sample (DZ01~05) of the upper member of Shahezi Formation were continuous sampling from Songke 2 well. U-Pb dating was performed on detrital zircons separated from the five sandstone samples. Detrital zircons from DZ01 to DZ05 has dominant ages of 105~140 Ma (268 grains), 155~200 Ma (160 grains), and 220~260 Ma (44 grains). This paper demonstrates that the provenance of the upper member of Shahezi Formation is came from the Central Great Xing’an Range. The depositional period of the Shahezi Formation constraints of maximum sedimentary age and reached to 111-115 Ma. At the same time, the Great Xing’an Range also provides sediments for the western Hailar Basin, which indicates that the Great Xing’an Range uplift and denudation during this period. The closure and collision of the Mongolia-Okhotsk ocean to the north and Pacific Plate subduction beneath the Asian continent to the east were the major tectonic events affecting the tectonic environment of the Great Xing’an Range.
In situ investigation of the impact of cyclic thermal variations impact on the mechanical properties of sandy soil.
Authors: Rosin-Paumier Sandrine , Eslami Hossein , Masrouri Farimah
Published: March 2020

The incorporation of heat exchangers into geostructures leads to changes in the temperature of the adjacent soil, which may affect its hydro-mechanical properties. In this study, mini-pressiometer tests were carried out in the vicinity of three experimental energy piles of 12 meters length and 0.52-meter diameter installed in saturated sandy soil. Tests were carried out in three locations and in two different depths (namely 3 and 4 meters in depth) before and after cyclic variations of their temperature. The pressuremeter parameters are the pressuremeter modulus EM, the limit pressure PL and the creep-pressure Pf. These parameters characterize the properties of the soils; some measurements were done close to the energy piles (1.25 meters from the center of the pile) using a mini-pressuremeter cell (380 mm in height and 28 mm in diameter). The comparison of the results before and after the four warming-cooling cycles (8° to 19° C) showed a thin thickening of the material at 3 meters depth. These results are coherent with in-lab measurements and with the results of the pile loading tests carried out later on the same site.
A shifting view of erosion and the carbon cycle
Authors: Hilton Robert , West Josh
Published: March 2020

Mountain building results in high rates of erosion and the interaction of rocks with the atmosphere, water and life. The resulting geochemical transfers may steer the evolution of the global carbon cycle and Earth’s long-term climate. For decades, much attention has focused on the weathering of silicate minerals and associated carbon dioxide (CO2) drawdown, and it is now understood that mountains are places where this reaction is most sensitive to changes in climate. However, the focus on silicate weathering belies a multi-faceted role for mountain building and erosion in the carbon cycle. Erosion also mobilises organic carbon from forests, transferring it to rivers and delivering it to long-lived sedimentary deposits, which results in an additional CO2 sink. In some mountain belts, exhumation of sedimentary rocks and exposure to the oxygen-rich atmosphere and hydrosphere can release CO2 by oxidation of rock organic carbon and sulfide minerals. These fluxes remain poorly constrained.

Here we take stock of our current understanding of all of these processes and the magnitude of their fluxes, focusing on insight from modern-river catchments. We find that the net CO2 budget associated with erosion and weathering appears to be controlled by processes that are not widely considered in conceptual or numerical models, specifically the fluxes from organic carbon burial and oxidation, and sulfuric acid weathering reactions. We suggest that lithology plays a major role in moderating the impact of mountain building on the global carbon cycle, with an orogeny dominated by sedimentary-rocks tending towards CO2 neutrality, or indeed becoming a CO2 source to the atmosphere. Over the coming century, erosion-induced changes in CO2 emissions from sedimentary rocks may result in a previously overlooked positive feedback on anthropogenic climate change.
Sensitivity analysis of divergence and underlying processes around organised convection with a cloud resolving model
Authors: Groot Edward , Tost Holger
Published: March 2020

In this study we are trying to understand (limits of) predictability related to (organised) convection and its upscale error growth.

For that purpose we aim to analyse the impact of three convection driving and amplifying processes, namely latent heat release, redistribution of moist static energy and convective momentum transport on the development of the convective cells. Furthermore, we plan to investigate uncertainties in these processes on downward propagation of the flow and ensemble spread.

The first results to be presented regard an idealised and strongly organised case of splitting convective storms modeled at different resolutions and with some small adaptations in the model convective cloud resolving model CM1. Currently processed resolution experiments show that both the actual divergence field and the processes supected to underlie it exhibit some sensitivity to model resolution on the subkilometre scale (100-1000 m). We can also show that the upper tropospheric divergence can be directly related to the latent heat release, as it is located vertically above the major latent heat releases. Nevertheless, neither the vertical redistribution of moist static energy nor the convective momentum transport are negligible and all three impact the divergent outflow of the convective storm.
Identifying Critical Input Parameters for Improving Drag-Based CME Arrival Time Predictions
Authors: Kay Christina
Published: March 2020

Coronal mass ejections (CMEs) typically cause the strongest geomagnetic storms so a major focus of space weather research has been predicting the arrival time of CMEs. Most arrival time models fall into two categories: (1) drag-based models that integrate the drag force between a simplified CME structure and the background solar wind and (2) full magnetohydrodynamic (MHD) models. Drag-based models typically are much more computationally efficient than MHD models, allowing for ensemble modeling. While arrival time predictions have improved since the earliest attempts,both types of models currently have difficulty achieving mean absolute errors below 10 hours. Here we use a drag-based model ANTEATR to explore the sensitivity of arrival times to various input parameters. We consider CMEs of different strengths from average to extreme size, speed, and mass (kinetic energies between 9x10^29 and 6x10^32 erg). For each scale CME we vary the input parameters to reflect the current observational uncertainty in each and determine how accurately each must be known to achieve predictions that are accurate within 5 hours. We find that different scale CMEs are the most sensitive to different parameters. The transit time of average strength CMEs depends most strongly on the CME speed whereas an extreme strength CME is the most sensitive to the angular width. A precise CME direction is critical for impacts near the flanks, but not near the CME nose. We also show that the Drag Based Model has similar sensitivities, suggesting that these results are representative for all drag-based models.

 
Spatiotemporal variability of soil penetration resistance in a field cultivated with sugarcane under conventional tillage system in northeast Brazil
Authors: Gomes de Almeida Brivaldo , Duarte Guedes Cabral de Almeida Ceres , Fernandes de Assunção Thaís , Campos Mantovanelli Bruno , Coelho de Araújo Filho José , Provenzano Giuseppe
Published: March 2020

Soil management, although intended to create favorable structural conditions for crop growth and development, without prior assessment of potential and limitations, has been one of the reasons for the degradation of natural resources. The effects on soil degradation and respective structural quality are generally evaluated by some physical soil attributes such as bulk density (BD), total porosity (TP) and soil penetration resistance (PR). The PR is recognized as a physical parameter that supports the identification of areas with different stages of compaction and thus can be used to define appropriate management for soil remediation. Besides, this parameter depends on intrinsic soil factors (texture, structure, and mineralogy) and soil water content (SWC). Therefore, PR increases with BD and decreases with SWC (gravimetric or volumetric). Thus, it is possible to establish the critical limit of PR (PRCL) associated with the value of SWC that limits the growth of plant roots. PRCL varies according to soil type and plant species, but 2.0 MPa is the value scientifically accepted as the critical value to limit the root growth. Thus, the paper aimed to evaluate the spatial and temporal variability of PR in a field cultivated with sugarcane, under the conventional tillage system. The research was carried out in the Carpina Sugarcane Experimental Station, Pernambuco, Brazil. A grid of 70 x 70 m was delineated at intervals of 10 m and in each point soil samples were collected in the layers 0 - 0.30 m and 0.30 - 0.60 m depth. Three samplings were done to determine gravimetric soil water content; the first after six months of subsoiling (Time 6) before harrowing and planting, the second after 12 months of subsoiling (Time 12, six months after harrowing and planting) and the last after 18 months of subsoiling, before harvesting (Time 18). In each sampling time, in situ PR tests were carried out with the Solo Track equipment (Falker® - Model PLG 5300) and the simultaneous values of gravimetric soil water content were determined and associated with the PR data. The results showed that soil water content had a weak degree of spatial dependence, indicating the need to increase the number of samples. On the other hand, the PR values showed that the subsoiling did not promote a positive effect on the soil physical quality, with values above the PRCL for root development in Time 6 (2.42 MPa), even if after one year the sugarcane root system acted positively, by reducing PR in Time 18 (1.04 MPa) below the critical value.
ONERA accelerometers for future gravity mission
Authors: Dalin Marine , Lebat Vincent , Boulanger Damien , Liorzou Francoise , Christophe Bruno , Rodrigues Manuel , Huynh Phuong-Anh
Published: March 2020

ONERA (the French Aerospace Lab) is developing, manufacturing and testing ultra-sensitive electrostatic accelerometer for space application. ONERA has procured the accelerometer for all the previous gravity missions (GRACE, GOCE, GRACE-FO) and works to improve the scientific return of the instruments.

One way is to propose an accelerometer with 3 sensitive linear acceleration measurements as well as 3 angular acceleration measurements for the attitude control or reconstruction. Two different configurations are proposed: CubSTAR, a miniaturized version with low accuracy but adapted for constellation or nanosat; and MicroSTAR, a high accuracy accelerometer.

CubSTAR accelerometer is a small volume instrument with the same performance on the 3 axes, the baseline being 20x20x20mm proof-mass in a 15x15x20cm volume envelope. A prototype was manufactured and tested during a drop-tower test. Moreover this prototype will be tested in vibration environment to check its good mechanical behavior.

MicroSTAR accelerometer is designed with a disruptive mechanical concept allowing using a 30x30x30mm proof-mass, with the same high-performance on the 3 axes. Modal and dynamic analyses have been performed and a prototype is under manufacturing.  
Assessing the impact of the urban landscape on heat wave episodes: a case study of the Metropolitan Area of Barcelona.
Authors: Villalba Gara , Ventura Sergi , Gilabert Joan , Martilli Alberto , Badia Alba
Published: March 2020

Currently, around 54% of the world's population is living in urban areas and this number is projected to increase by 66% by 2050. In the past years, cities have been experiencing heat wave episodes that affect the population. As the modern urban landscape is continually evolving, with green spaces and parks becoming a more integral component and with suburbs expanding outward from city centres into previously rural, agricultural, and natural areas, we need tools to learn how to best implement planning strategies that minimize heat waves.  In this study we use the Weather and Research Forecasting model (WRF) with a multi-layer layer scheme, the Building Effect Parameterization (BEP) coupled with the Building Energy Model (BEP+BEM, Salamanca and Martilli, 2010) to take into account the energy consumption of buildings and anthropogenic heat generated by air conditioning systems. The urban canopy scheme takes into account city morphology (e.g. building and street canyon geometry) and surface characteristics (e.g. albedo, heat capacity, emissivity, urban/vegetation fraction). The Community Land Surface Model (CLM) is used in WRF that uses 16 different plant functional types (PFTs) as the basis for land-use differentiation.  Furthermore, we use the Local Climate Zones (LCZ) classification which has 11 urban land use categories with specific thermal, radiative and geometric parameters of the buildings and ground to compute the heat and momentum fluxes in the urban areas.  The objective is to validate the model and establish relationships between urban morphology and land use with temperature, so that the model can be used to simulate land use scenarios to investigate the effectiveness of different mitigation strategies to lower urban temperatures during the summer months.

 

We test the methods with the Metropolitan Area of Barcelona (AMB) as a case study. The AMB is representative of the Mediterranean climate, with mild winters and hot summers. With a heterogeneous urban landscape, the AMB covers 636 km2 (34% built, 23% agricultural, and 31% vegetation) and has more than five million habitants. We simulate the heat wave that occurred in August 2018, during which temperatures stayed between 30 and 40ºC for five consecutive days and compare results with observed data from five different weather stations. We then simulate a potential scenario changing land surface from built to vegetation, in accordance with Barcelona´s strategic climate plan, and the potential impact the land use change has on reducing heat wave episodes.
Ionization profile of meteors from simultaneous video and radio forward scatter observations
Authors: Lamy Hervé , Anciaux Michel , Ranvier Sylvain , Calegaro Antoine , Johannink Carl
Published: March 2020

In this study, optical video observations of meteors with the CAMS (Camera for All-sky Meteor Surveillance)-BeNeLux network and radio forward scatter observations with the BRAMS (Belgian RAdio Meteor Stations) network obtained on 4-5 October 2018  are combined in order to obtain an ionization profile along a meteor path.

The trajectory, initial speed and deceleration parameters of a given meteor are provided by the CAMS-BeNeLux data. For a given trajectory, the positions of the specular reflection points for radio waves are computed for each combination of a given BRAMS receiving station and the BRAMS transmitter. For each receiving station which recorded a meteor echo (depending on the geometry and the SNR ratio), the power profile is computed and the peak power values of the underdense meteor profiles are used to determine the ionization (electron line density) at the various specular reflection points along the meteor path. This is done using the McKinley (1961) formula which is strictly valid for underdense meteor echoes.  We discuss how we compute the gains of the antennas, the polarization factor, and how the peak power values are transformed from arbitrary units into watts using the signal recorded from a device called the BRAMS calibrator. We also discuss how to extend this study to overdense meteor echoes or those with intermediate electron line densities.

Finally, these results are combined with a simple ablation meteor model in order to obtain an estimate of the initial mass of the meteoroid.

Mc Kinley D.W.R., Meteor science and engineering, Mc Graw-Hill eds, 1961
Wobbles in the Early Cambrian Earth's spin axis? New high-quality paleomagnetic data from NE Brazil
Authors: Antonio Paul Yves Jean , da Trindade Ricardo Ivan ferreira , Hollanda Maria Helena B. M. , Giacomini Bruno
Published: March 2020

The Neoproterozoic-Paleozoic transition (~541 Ma) was a turning point in Earth’s history resulting in great biological changes between the microbial Precambrian life and the Ediacaran biotic revolution with the occupation of the sedimentary substrate, the dawn of biomineralization and the appearance of the earliest multicellular organisms. In parallel, this period is marked by a large plate reorganization leading to the assembly of Gondwana and by major climatic changes (extreme glacial events). Due in part to a poor paleomagnetic database for the different cratons in the Ediacarian-Cambrian times, the global paleogeography at that time still remains controversial. In this study we present a new paleomagnetic pole (Q= 6) for the Monteiro dike swarms in the Borborema Province (NE Brazil). They are fine-grained hornblende dolerite dated by U-Pb on zircon at ~538 Ma. Rock magnetic data indicate that magnetite and pyrrhotite are the main remanence carriers. Positive baked-contact tests support the primary remanence obtained for these dikes (19 sites). A positive reversal test (classified C) was also obtained from the 14 sites with normal polarity and the 5 sites with reversed polarity, indicating that the secular variations was eliminated with our sampling. Our new key pole is not consistent with the classical Apparent Polar Wander Path of the West Gondwana which consists of a long track from a southern polar position at ~590 Ma to an equatorial position at ~520 Ma. The Monteiro paleomagnetic pole suggest instead rapid and small oscillations of the APW, or wobbles, after 560 Ma. These rapid oscillations may be related to inertial readjustments in response to true polar wander (TPW) of the spin axis. TPW events have been suggested from 615 to 590 and then from 575 to 565 Ma in previous works. These TPWs are supposedly caused by changes in the inertia tensor of the Earth due to internal mass redistribution, related to rapid changes in subduction velocity. Possible links between these events and life evolution will also be discussed.
A unique ~12 ka subaerial record of rift-transform triple-junction tectonics, NE Iceland
Authors: Rust Derek , Whitworth Malcolm
Published: March 2020

In northern Iceland the European-North American plate boundary is broad and complex but includes a remarkable subaerial triple-junction intersection between the Husavik-Flatey Fault (HFF) dextral transform and rifting in the Northern Volcanic Zone. Fortuitously, the triple junction occurs in a sheet of ~12 ka pahoehoe lavas; a tabula rasa recording innumerable fault features displayed in exquisite detail. High-resolution drone imagery, coupled with 120 field measurements of fault slip directions and opening amounts, made possible the mapping and analysis of this detail and, importantly, enabled recognition and exclusion of potentially misleading primary deformation features associated with emplacement of the lavas. Rift-transform interactions in this natural laboratory have remained spatially stable throughout post-glacial time, although with transform-affinity faults reactivated to accommodate rift extension and transform ‘encroachment’ into the rift domain. First-order en-echelon Riedel fault complexes are recognised, linked by transpressional faulting and compressional strike-slip relay ramps, as well as second-order R shears, R’ and P shears, and previously undescribed R’ Riedel-in- Riedel relationships. A pahoehoe flow front offset along a first-order Riedel fault complex records slip at ~3.8 mm a−1, which may be consistent with the published GPS-based current slip-rate estimate of ~6.8 mm a−1 across the HFF as a whole.
The Radio and Plasma Waves (RPW) Instrument on Solar Orbiter : Capabilities, Performance and First results.
Authors: Maksimovic Milan , Souček Jan , Bale Stuart D. , Bonnin Xavier , Chust Thomas , Khotyaintsev Yuri , Kretzschmar Matthieu , Plettemeier Dirk , Steller Manfred , Štverák Štěpán
Published: March 2020

We will review the instrumental capabilities of the Radio and Plasma Waves (RPW) Instrument on Solar Orbiter which at the time of writing this abstract is planned for a launch on February 5th 2020. This instrument is designed to measure in-situ magnetic and electric fields and waves from 'DC' to a few hundreds of kHz. RPW will also observe solar radio emissions up to 16 MHz. The RPW instrument is of primary importance to the Solar Orbiter mission and science requirements, since it is essential to answer three of the four mission overarching science objectives. In addition, RPW will exchange on-board data with the other in-situ instruments, in order to process algorithms for interplanetary shocks and type III Langmuir waves detections. If everything goes well after the launch, we will hopefully be able to present the first RPW data and results gathered during the commissioning.
Earthquake rupture properties and tsunamigenesis in the shallowest megathrust
Authors: Sallares Valenti , Ranero Cesar R. , Prada Manel , Calahorrano B. Alcinoe
Published: March 2020

Seismological data provide compelling evidence of a depth-dependent rupture behavior of megathrust earthquakes. Relative to deeper events of similar magnitude, shallow earthquake ruptures have larger slip and longer duration, radiate energy that is depleted in high frequencies and have a larger discrepancy between their surface wave and moment magnitudes (MS and MW, respectively). These source properties make them prone to generating devastating tsunamis without clear warning signs. The origin of the observed differences has been a long-lasting matter of debate. Here we first show that the overall depth trends of all these observations can be explained by worldwide average variations of the elastic properties of the rock body overriding the megathrust fault, which deforms by dynamic stress transfer during co-seismic slip, and we discuss some general implications for tsunami hazard assessment. Second, we test this conceptual model for the particular case of the 1992 Nicaragua tsunami earthquake (MS7.2 and MW7.8). This event nucleated at ~20 km-deep but it appears to have released most of its seismic moment near the trench. This earthquake caused mild shaking and little damage, so that tsunami hazard based on human perception was underestimated and the destructive tsunami hit the coast unexpectedly. We use a set of 2D seismic data to map the P-wave seismic velocity above the inter-plate boundary, and we combine it with previously estimated moment release distribution to calculate slip and stress drop distributions and moment-rate spectra that are compatible with both the seismological and the geophysical data. The models confirm that slip concentrated in the shallow megathrust, with two patches of maximum slip exceeding 10-12 m in the near-trench zone that can explain the observed tsunami run-up, while the average stress drop is ~3 MPa. The low rigidity of the upper plate in the zone of maximum slip explains the high frequency depletion and the resulting MW-MS discrepancy without need to consider anomalous rupture properties or fault mechanics
Non-ergodic FAS Ground-Motion Model for France
Authors: Sung Chih Hsuan , Abrahamson Norman , Kuehn Nicolas , Traversa Paola , Zentner Irmela
Published: March 2020

In this study, we use an ergodic ground motion model (GMM) of California of Bayless and Abrahamson (2019) as a backbone and incorporate the varying-coefficient model (VCM) to develop a new French non-ergodic GMM based on the French RESIF data set (1996-2016). Most of the magnitudes of this database are small (Mw = 2.0 – 5.2), so we adopt the Fourier amplitude spectral GMM rather than the spectral acceleration model, which allows the use of small magnitude data to constrain path and site effects without the complication of the scaling being affected by differences in the response spectral shape. For the VCM, the coefficients of GMPE can vary by geographical location and they are estimated using Gaussian process regression. That is, there is a separate set of coefficients for each source and site coordinate, including both the mean coefficients and the epistemic uncertainty in the coefficients. Moreover, the epistemic uncertainty associated with the predicted ground motions also varies spatially: it is small in locations where there are many events or stations and it is large in sparse data regions. Finally, we modify the anelastic attenuation term of a GMM by the cell-specific approach of Kuehn et al. (2019) to allow for azimuth-dependent attenuation for each source which reduces the standard deviation of residuals at long distances. The results show that combining the above two methods (VCM & cell-specific) to lead an aleatory standard deviation of residuals for the GMM that is reduced by ~ 47%, which can have huge implications for seismic-hazard calculations.
Physics is everywhere!
Authors: Filep Doina Otilia
Published: March 2020

Physics is everywhere!

Europeana Collections provides access to over 50 million digitised items – books, music, artworks and more – with sophisticated search and filter tools to help you find what you’re looking for: https://www.europeana.eu/portal/hu    

 I do many activities with my students, related to the connections between science and art.

Science it’s everywhere, even in the pictures! The main idea is to find science(physics) in pictures representing the everyday life activities, the living and inanimate nature (rocks, monuments, buildings, water, mountains, air etc.).

During the activities, students collect and save images from the Europeana Galleries interface. Selected and saved images must be linked to a science(physics)-related phenomenon. A brief description of the physics corresponding to the images is then provided. For example: a possible text written on an image depicting ice caps: state change, freezing of water, temperature; on an image depicting a car: movement, speed, acceleration; rainbow: an optical phenomenon of light refraction, electromagnetic spectrum, and different wavelengths; the red colour of setting sun: wavelengths, white sunlight components, light absorption and scattering, atmosphere of the earth, molecules in the air... Of course the scientific level of the description depends of the level of age and knowledge of students. This is a good method to clarify the connection of learned concepts with everyday life, the possible misconceptions and to develop students' scientific vocabulary.

The methodological idea is to find science(physics) of everyday life in art (painting, graphics, and photos). In our lesson, the students identified general physical phenomena and processes in the reviewed art collections. It was an opportunity to discuss about many physical phenomena, discuss concepts, and clarify misconceptions. Several physical phenomena have been discovered about children in a single picture. They were very enthusiastic. The groups tried to override each other. It was an experience to discuss the pictures presented: who sees what? How do you build a bridge between physics and art?

I realised, that the pupils were much more courageous; talking about the prior knowledge they had seen and discovered in the pictures. The methodological idea that we have tested can serve as a guide for the introduction of different topics that are already known to students, or even new science topics, in an unusual motivating way. Targeting a picture in a targeted way, we can introduce a new topic, an experiment- thus enhancing the physics lesson and motivating the students. They may also be able to think of different physics-related posters in design and drawings.

With Internet applications, they can create more tasks, using images.
Abrupt changes across the Arctic permafrost region endanger northern development
Authors: Teufel Bernardo , Sushama Laxmi
Published: March 2020

Extensive degradation of near-surface permafrost is projected during the 21st century, which will have detrimental effects on northern communities, ecosystems and engineering systems. This degradation will expectedly have consequences for many processes, which most previous modelling studies suggested would occur gradually. Here, we project that soil moisture will decrease abruptly (within a few months) in response to permafrost degradation over large areas of the present-day permafrost region, based on analysis of transient climate change simulations performed using a state-of-the-art regional climate model. This regime shift is reflected in abrupt increases in summer near-surface temperature and convective precipitation, and decreases in relative humidity and surface runoff. Of particular relevance to northern systems are changes to the bearing capacity of the soil due to increased drainage, increases in the potential for intense rainfall events and increases in lightning frequency, which combined with increases in forest fuel combustibility are projected to abruptly and substantially increase the severity of wildfires, which constitute one of the greatest risks to northern ecosystems, communities and infrastructure. The fact that these changes are projected to occur abruptly further increases the challenges associated with climate change adaptation and potential retrofitting measures.
The role of internal variability in climate change projections of North American surface air temperature and temperature extremes in CanESM2 large ensemble simulations
Authors: Yu Bin , Li Guilong , Chen Shangfeng , Lin Hai
Published: March 2020

Recent studies indicated that the internal climate variability plays an important role in various aspects of projected climate changes on regional and local scales. Here we present results of the spreads in projected trends of wintertime North American surface air temperature and extremes indices of warm and cold days over the next half-century, by analyzing a 50-member large ensemble of climate simulations conducted with CanESM2. CanESM2 simulations confirm the important role of internal variability in projected surface temperature trends as demonstrated in previous studies. Yet the spread in North American warming trends in CanESM2 is generally smaller than those obtained from CCSM3 and ECHAM5 large ensemble simulations. Despite this, large spreads in the climate means as well as climate change trends of North American temperature extremes are apparent in CanESM2, especially in the projected cold day trends. The ensemble mean of forced climate simulations reveals high risks of warm days over the western coast and north Canada, as well as a weakening belt of cold days extending from Alaska to the northeast US. The individual ensemble members differ from the ensemble mean mainly in magnitude of the warm day trends, but depart from the ensemble mean in conspicuous ways, including spatial pattern and magnitude, of the cold day trends. The signal-to-noise ratio pattern of the warm day trend resembles that of the surface air temperature trend; with stronger signals over north Canada, Alaska, and the southwestern US than the midsection of the continent. The projected cold day patterns reveal strong signals over the southwestern US, north Canada, and the northeastern US. In addition, the internally generated components of temperature and temperature extreme trends exhibit spatial coherences over North America, and are comparable to the externally forced trends. The large-scale atmospheric circulation-induced temperature variability influences these trends. Overall, our results suggest that climate change trends of North American temperature extremes are likely very uncertain and need to be applied with caution.
Evaluating P sustainability using biosolids in comparison to commercial fertilizer for P-use efficient genetically transformed lettuce
Authors: Chan Neng Iong , Rittmann Bruce , Elser James
Published: March 2020

The sustainable management of phosphorus (P) includes recycling and enhancing P-use efficiency (PUE) in agriculture.  In this study, we compared plant yield and the PUE of lettuce growing with soil amendments of biosolids from three wastewater treatment plants in comparison to commercial fertilizer.  Furthermore, we used AVP1-transformed lettuce (Lactuca sativa cv. Conquistador), which is genetically improved to enhance its PUE, and compared its performance to non-transformed (wildtype, WT) lettuce in greenhouse conditions.  AVP1 lettuce produced higher yield than WT lettuce only with commercial-fertilizer treatments; the yield with biosolid treatments did not vary between the two lettuce types.  PUE did not differ between WT and AVP1 lettuce but was higher for commercial fertilizer than for biosolids.  WT lettuce had higher P content in below-ground biomass than AVP1 lettuce when both were treated with biosolids.  This suggests that capability of AVP1 lettuce to acidify the root zone may have mobilized heavy metals from biosolids and these toxins reduced the yield, P uptake, and PUE in AVP1 lettuce.  In particular, Cd and As contents were high in lettuce biomass from biosolid treatments and exceeded recommendations for human daily oral dose.
Climate change reshapes the drivers of false spring risk across European trees
Authors: Chamberlain Catherine , Cook Benjamin , Morales-Castilla Ignacio , Wolkovich Elizabeth
Published: March 2020

Temperate and boreal forests are shaped by late spring freezing events after budburst, which are also known as false springs. Research has generated conflicting results on whether or not these events will change with climate change, potentially because---to date---no study has compared the myriad climatic and geographic factors that contribute to a plant's risk of a false spring. We assessed and compared the strength of the effects of mean spring temperature, distance from the coast, elevation and the North Atlantic Oscillation (NAO) using PEP725 leafout data for six temperate, decidious tree species across 11,648 sites in Central Europe and how these predictors shifted with climate change. Across species before recent warming, mean spring temperature and distance from the coast were the strongest predictors, with higher mean spring temperatures associated with decreased risk in false springs (–7.64% per 2°C increase) and sites further from the coast experiencing an increased risk (5.32% per 150km from the coast). Elevation (2.23% per 200m increase in elevation) and NAO index (1.91% per 0.3 increase) also increased false spring risk. 

With climate change, elevation and distance from coast---i.e., the geographic factors---remain relatively stable, while climatic factors shifted in magnitude for mean spring temperature (down to -2.84% in risk per 2°C), and in direction, with positive NAO phases leading to lower risk (-9.15% per 0.3). The residual effects of climate change---unexplained by the climatic and geographic factors already included in the model---magnified the species-level variation in risk, with risk increasing among early-leafout species (i.e., Aesculus hippocastanum, Alnus glutinosa and Betula pendula) but a decline or no change in risk among late-leafout species (i.e., Fagus sylvatica, Fraxinus excelsior and Quercus robur). Our results show that climate change has reshaped the major drivers of false spring risk and highlight how considering multiple factors can yield a better understanding of the complexities of climate change.
Coupling wildfire spread and erosion models to quantify post-fire erosion in Northern Sardinia, Italy
Authors: Del Giudice Liliana , Arca Bachisio , Robichaud Peter , Ager Alan , Canu Annalisa , Duce Pierpaolo , Pellizzaro Grazia , Ventura Andrea , Alcasena-Urdiroz Fermin , Spano Donatella , Salis Michele
Published: March 2020

High severity wildfires can have many negative impacts on ecosystems. In this work, we coupled wildfire spread and erosion prediction modelling to evaluate the effects of fuel reduction treatments in preventing soil runoff in Mediterranean ecosystems. The study was carried out in a 68,000-ha forest area located in Northern Sardinia, Italy. We treated 15% of the study area, and compared no-treatment conditions vs alternative strategic fuel treatments. We estimated pre- and post-treatment fire behaviour by using the Minimum Travel Time (MTT) fire spread algorithm. For each fuel treatment scenario, we simulated 25,000 wildfires replicating the historic weather conditions associated with severe wildfires in the area. Sediment delivery was then estimated using the Erosion Risk Management Tool (ERMiT). Our results showed how post-fire sediment delivery varied among and within the fuel treatment scenarios tested. The treatments realized nearby roads were the most efficient. We also evaluated the effects of other factors such as exceedance probability, time since fire, slope, fire severity and vegetation type on post-fire sediment delivery. This work provides a quantitative assessment approach to inform and optimize proactive risk management activities aimed at reducing post-fire erosion in Mediterranean areas.