bluuebunny/crossref_metadata_2025 huggingface dataset:
A táncos test: egészség, testi elégedettség, testhez való viszony, evési attitűdök és önértékelés vizsgálata táncosok körében
Authors: Szászi Beáta , Szabó Pál
Published: March 2021

A szerzők célkitűzése az egészségi állapot, a testtel kapcsolatos elégedettség, az evészavarok tüneteinek, a testtel kapcsolatos befektetések és az önértékelés kérdőíves vizsgálata felnőtt táncosok körében.Módszerek: Goldberg-féle Általános Egészségi Kérdőív, WHO Általános Jóllét Skála, Testtel Kapcsolatos Elégedettség Skálája, Emberalakrajzok Tesztje, Testtel Kapcsolatos Befektetések Skálája, Evési Attitűdök Tesztje és a Rosenberg Önértékelés Skála.Eredmények: A női táncosok (n=71) 45,8%-a, a férfiak (n=35) 21,2%-a rendelkezik jelentősebb tünetekkel vagy betegséggel. A nők 7,4%-a (n=5) sovány, túlsúlyos a nők 5,9%-a (n=4), a férfiak 15,6%-a (n=5). A nők 11,6%-ánál (n=8) fennáll az evészavarok kockázata. A modern társastáncosok a legelégedetlenebbek a testükkel, testsúlyukkal, náluk gyakoribbak az evészavar tünetek, míg a modern táncosok a legvédettebbek a testtel kapcsolatos szélsőségek terén. A 20 év alatti táncosnők szigorúbban ítélik meg és kevésbé védik a testüket, több bulimiás tünetük van, alacsonyabb az önértékelésük.Következtetések: A táncoktatásban elméleti és gyakorlati tudást adó intervenciós program bevezetése szükséges, melyben az egészségügyi, oktatási és nevelési munkatársak is részt vesznek. Mindez elősegítheti a táncosok testi-lelki egészségének és állóképességének javulását, a pozitív testképet, a magasabb önértékelést és az evészavaros tünetek csökkenését.
Munca pe platformele digitale de livrare din România
Authors: Bădoi Delia
Published: March 2021

This paper shortly presents the research project “Employment strategies in the context of new vulnerabilities of the digitalisation process” GAR-UM- 2019- XI – 5.4 – 1, financed by the GAR-UM- 2019 Romanian Academy Programme, 2019–2022.
Evaluating the Causes and Impact of Change Orders on Construction Projects Performance in Oman
Authors:   Student, Sohar University, Al Maamari Amira , Khan Firdouse ,   Sohar University
Published: March 2021

Purpose of the study: The purpose of the study was to investigate the factors causing the change orders in construction projects and to assess their impact on the project's performance in Oman. Design/Methodology/Approach: The study was conducted using a random sampling technique. The questionnaire was used to collect data from215contractingcompanies located in Muscat Governorate, Oman. Statistical analyses such as the chi-square test, Kolmogorov-Smirnov, and linear regression tests were used. Findings: The result of the study showed that the variations have more impacts on the project and the change orders harm the project most. It was also revealed that 'change in specifications’, ‘Alterations in design and drawing' and Time lag in the project implementation were considered to be the primary causes of change orders, and ‘Change of scope’, ‘Errors and omissions in design' and 'Insufficient Logistics’ were the primary causes of variations affecting the construction projects in Oman. Research Implications: It was suggested to plan for a strategy to avoid the time lag and to take up adequate financial pre-planning to maximize the profit. Social Implications: The findings of the study help the companies to take proactive measures to eliminate or reduce unnecessary variations and change orders to accomplish the prime objectives of such projects. Originality/value: This is the first study of its kind in bringing out the issues related to change orders and variations in the construction projects of Muscat Governorate, Oman. Keywords: Change Orders, Variations, Causes and Impacts on the Construction Projects, Construction Projects in Oman, Clients, Contractors, and Consultants.
Online Information Searching Skills of Business Students
Authors: Tariq Muhammad , Rehman Shafiq Ur , Mahmood Khalid , Mustafa Ghulam
Published: March 2021

This study investigates the perceived level and sources of learning Online Information Searching (OIS) skills of the students of business studies. The study also explores the differences in the students' searching skill level of information resources, based on their selected personal and academic variables including gender, age, type of university, level of degree and major academic subjects. A cross-sectional survey research method was used to collect data on a self-reporting questionnaire. Business students of undergraduate, graduate and postgraduate levels from 24 public and private sector universities of Lahore, Pakistan were selected through convenient sampling technique. Total population of this study was 114,500. With the margin error of 5% and confidence level of 97%, the sample of this study was 470 students. The study found a satisfactory level of students' searching skills. There was no significant difference in the skills based on various variables like gender, age, type of university and level of degree. However, short courses and training workshops had a positive impact on the level of skills. There is a lack of research on the topic and this paper will fill the gap in existing literature. This study will be helpful for Library Information Service (LIS) academicians, librarians, professional associations and LIS trainers to design and implement training programs for university students in the area of OIS. This study will also be helpful for Higher Education Commission (HEC) national digital library for selection of appropriate databases for business students.
Sentidos da festa à brasileira
Authors: Amaral Rita de Cássia
Published: March 2021

Frequentemente ouvimos dizer que “no Brasil tudo acaba em festa”. Esta associação entre o caráter brasileiro e a festa deixa transparecer a percepção de uma certa displicência, “alienação” e descaso com as normas e a ordem, imediatamente referidas ao Carnaval (notadamente um tempo em que se supõe ser possível quebrar ou subverter regras) e às inúmeras outras festas que acontecem no país. Tanto dentro do Brasil, como no exterior, somos considerados o “país do Carnaval” (e o dicionário registra que a palavra carnaval também significa “confusão, desordem, trapalhada”) e da alegre irresponsabilidade, o que implica o impulso para festejar como definidor da imagem internacional e da auto-imagem brasileira, sendo, portanto, um traço distintivo da identidade nacional. “O Brasil”, teda afirmado o presidente da França Charles de Gaulle, "não é um país sério”. Mas será que festejar se opõe à responsabilidade e à consciência social? A cidadania? Ao enfrentamento de problemas? [...]
Málarias, migrações e grandes projetos na Amazônia
Authors: Najar Alberto
Published: March 2021

A relação entre o enorme crescimento da malária no Brasil e particularmente na região Amazônica não é, como procuram insinuar alguns documentos oficiais, uma consequência das condições climáticas. Estas explicações procuram passar uma idéia desbravadora e pioneira cuja contrapartida são os inevitáveis custos para a saúde. Tudo acaba indo para a conta do progresso. Quando muito, admite-se que “componentes sócio-econômicos representem fatores importantes na transmissão da malária" (Arcoverde, 1985) prevalecendo a visão de que os determinantes da história da endemia são fatores biológicos e ecológicos num sentido restrito.. [...]
Rompendo barreiras
Authors: Silva Elanine Cristina Camillo da
Published: March 2021

Considerando que o Brasil é meta de migrantes vindos de países latino-americanos, asiáticos, africanos, evidencia-se a pertinência de um estudo sobre essa presença no âmbito das relações assistenciais, também na saúde. De fato, recentes publicações versam sobre a fruição do direito à saúde por estrangeiros (e brasileiros não residentes) na região de fronteira, entre o Brasil e os países do Mercado Comum do Sul (MERCOSUL).[...]
Migrações internas e internacionais motivadas por orientação sexual e identidade de gênero
Authors: Andrade Vítor Lopes
Published: March 2021

Apesar das migrações internas e internacionais motivadas por orientação sexual e identidade de gênero serem antigas e ainda hoje muito recorrentes, a reflexão teórica especificamente sobre esses deslocamentos se iniciou somente nos anos 2000. O objetivo deste texto é evidenciar que identidade de gênero e orientação sexual são categorias analíticas importantes para os estudos de mobilidade humana. Para tanto, inicialmente discorrer-se-á acerca de migrações internas – isto é, dentro de um mesmo território nacional – motivadas por orientação sexual. Na sequência, discutir-se-á as migrações internacionais envolvendo pessoas não-heterossexuais. Por fim, uma atenção especial será dada a um tipo específico de migração internacional: o refúgio baseado em perseguição ou temor de perseguição por orientação sexual e identidade de gênero.
ІНТЕГРУВАННЯ ДИФУЗІЙНИХ ПРОЦЕСІВ РОЗПОВСЮДЖЕННЯ РАДІОНУКЛІДІВ ТА НЕБЕЗПЕЧНИХ ХІМІЧНИХ РЕЧОВИН ДО ІНФОРМАЦІЙНИХ МОДЕЛЕЙ ХІМІЧНОЇ ТА РАДІАЦІЙНОЇ ОБСТАНОВКИ
Authors: Поплавець Сергій , Гишко Генадій , Колмогоров Олексій , Лясковський Вадим , Чепурний В’ячеслав , Третяк Дар’я
Published: March 2021

Розглянуті дифузійні процеси розповсюдження радіонуклідів та небезпечних хімічних речовин, що є вихідними даними для формування інформаційних моделей хімічної та радіаційної обстановки. Дифузійні процеси розповсюдження радіонуклідів і небезпечних хімічних речовин в атмосфері враховуються при моделюванні атмосферної дисперсії в наслідок руйнування радіаційних та хімічно-небезпечних об’єктів за допомогою комп’ютерних програм і алгоритмів.
Comparison of ozone measurement methods in biomass burning smoke: an evaluation under field and laboratory conditions
Authors: Long Russell W. , Whitehill Andrew , Habel Andrew , Urbanski Shawn , Halliday Hannah , Colón Maribel , Kaushik Surender , Landis Matthew S.
Published: March 2021

Abstract. In recent years wildland fires in the United States have had significant
impacts on local and regional air quality and negative human health
outcomes. Although the primary health concerns from wildland fires come from
fine particulate matter (PM2.5), large increases in ozone (O3)
have been observed downwind of wildland fire plumes (DeBell et al., 2004;
Bytnerowicz et al., 2010; Preisler et al., 2010; Jaffe et al., 2012;
Bytnerowicz et al., 2013; Jaffe et al., 2013; Lu et al., 2016; Lindaas et
al., 2017; McClure and Jaffe, 2018; Liu et al., 2018; Baylon et al., 2018;
Buysse et al., 2019). Conditions generated in and around wildland fire
plumes, including the presence of interfering chemical species, can make the
accurate measurement of O3 concentrations using the ultraviolet (UV)
photometric method challenging if not impossible. UV photometric method
instruments are prone to interferences by volatile organic compounds (VOCs)
that are present at high concentrations in wildland fire smoke. Four
different O3 measurement methodologies were deployed in a mobile
sampling platform downwind of active prescribed grassland fire lines in
Kansas and Oregon and during controlled chamber burns at the United States
Forest Service, Rocky Mountain Research Station Fire Sciences Laboratory in
Missoula, Montana. We demonstrate that the Federal Reference Method (FRM)
nitric oxide (NO) chemiluminescence monitors and Federal Equivalent Method
(FEM) gas-phase (NO) chemical scrubber UV photometric O3 monitors are
relatively interference-free, even in near-field combustion plumes. In
contrast, FEM UV photometric O3 monitors using solid-phase catalytic
scrubbers show positive artifacts that are positively correlated with carbon
monoxide (CO) and total gas-phase hydrocarbon (THC), two indicator species
of biomass burning. Of the two catalytic scrubber UV photometric methods
evaluated, the instruments that included a Nafion® tube dryer
in the sample introduction system had artifacts an order of magnitude
smaller than the instrument with no humidity correction. We hypothesize that
Nafion®-permeating VOCs (such as aromatic
hydrocarbons) could be a significant source of interference for catalytic
scrubber UV photometric O3 monitors and that the inclusion of a
Nafion® tube dryer assists with the mitigation of
these interferences. The chemiluminescence FRM method is highly recommended
for accurate measurements of O3 in wildland fire plume studies and at
regulatory ambient monitoring sites frequently impacted by wildland fire
smoke.
Characteristics of fragmented aurora-like emissions (FAEs) observed on Svalbard
Authors: Dreyer Joshua , Partamies Noora , Whiter Daniel , Ellingsen Pål G. , Baddeley Lisa , Buchert Stephan C.
Published: March 2021

Abstract. This study analyses the observations of a new type of small-scale aurora-like feature, which is further referred to as fragmented aurora-like emission(s) (FAEs). An all-sky camera captured these FAEs on three separate occasions in 2015 and 2017 at the Kjell Henriksen Observatory near the arctic town of Longyearbyen, Svalbard, Norway. A total of 305 FAE candidates were identified.
They seem to appear in two categories – randomly occurring individual FAEs and wave-like structures with regular spacing between FAEs alongside auroral arcs. FAEs show horizontal sizes typically below 20 km, a lack of field-aligned emission extent, and short lifetimes of less than a minute. Emissions were observed at the 557.7 nm line of atomic oxygen and at 673.0 nm (N2; first positive band system) but not at the 427.8 nm emission of N2+ or the 777.4 nm line of atomic oxygen. This suggests an upper limit to the energy that can be produced by the generating mechanism. Their lack of field-aligned extent indicates a different generation mechanism than for aurorae, which are caused by particle precipitation. Instead, these FAEs could be the result of excitation by thermal ionospheric electrons. FAE observations are seemingly accompanied by elevated electron temperatures between 110–120 km and increased ion temperatures at F-region altitudes. One possible explanation for this is Farley–Buneman instabilities of strong local currents. In the present study, we provide an overview of the observations and discuss their characteristics and potential generation mechanisms.
The structural state of agro-grey soil in various tillage conditions (based on aggregate and rheological analyses)
Authors: Mishchenko Anastasia , Khaydapova Dolgor , Karpova Dina , Abdulkhanova Dina , Shulga Pavel
Published: March 2021

The aggregate composition is one of the key characteristics of soils. Based on the use of aggregates of different sizes, one can draw conclusions about the anthropogenic load on soils in conditions of agricultural use. We investigated the aggregate composition of soil samples of the 0-20 cm layer of soils with application of four tillage techniques: plowing, energy-saving (surface tillage, without plowing), longline (surface tillage + chisel tillage), anti-erosion (chisel tillage). Stationary experience laid in 1995. The сrops were: bare fallow, busy fallow and wheat. Soil samples were sieved with a standard set of sieves:> 10; 10-7; 7-5; 5-3; 3-2; 2-1; 1-0.5; 0.5-0.25; <0.25 mm, water resistance was determined by the Savvinov method with sieves of:> 5; 5-3; 3-2; 2-1; 1-0.5; 0.5-0.25; <0.25 mm with daily water saturation prior to analysis. Rheological parameters were studied using the amplitude sweep method on a modular compact rheometer MCR-302 (Anton Paar, Austria) with a parallel plateau PP-25 measuring system.

All 24 plots with all four treatments demonstrated an excellent water-resistant structure of agro-gray soils. The soils have a good structural state in terms of agronomically aggregates content and the structural coefficient. Water resistance of the structure is excessively high and good as well. The average diameter of the aggregates is from 3.6 to 6.1 mm, the average value is 4.7 mm. This gives us an idea of the structural condition in general, but we cannot track the structural condition of plots with different treatments in the field.

The Principal Component analysis and cluster analysis was used to determine the differences in soils of different types of use. We used STATISTICA. These statistics method successfully classified soils structural relatively treatments.

The study of the rheological properties of agro-gray soils with different processing methods showed that in the zone of linear viscoelastic behavior (LV[С1] B) during all treatments, the range of LVB did not differ significantly and averaged 0.0048% deformation. Differences were noted at Shear Stress max, for the energy-saving treatment application, the τ (632.67 Pa) was lower than the other treatments, an average of 661.83 Pa for 12 repetitions. The crossover occurred at 1.48% strain for an average of 12 reps. The smallest value for the deformation at which crossover occurred (1.22%) was observed for the variant with the use of anti-erosion treatment. The highest (1.72%) for energy efficient processing.

Thus, the use application of aggregate and rheological analyses has shown the promotion of energy-saving technologies application to form a relatively favorable structural condition of the studied soils.

The work was supported by RFBR grant No 19-29-05021 mk
Estimating melt pond bathymetry from aerial images using photogrammetry
Authors: Fuchs Niels , König Marcel , Birnbaum Gerit
Published: March 2021

Melt ponds play a key role for the summery energy budget of the Arctic sea-ice surface. Observational data that enable an integrated understanding and improved formulation of the thermodynamic and hydrological pond system in global climate models are spatially and temporally limited.

Previous studies of shallow water bathymetry of riverbeds and lakes, experimental studies above sea ice and increasing availability of high-resolution aerial sea ice imagery motivated us to investigate the possibilities to derive pond bathymetry from photogrammetric multi-view reconstruction of the summery ice surface topography.

Based on dedicated flight grids and simple assumptions we were able to obtain pond depth with a mean deviation of 3.5 cm compared to manual in situ observations. The method is independent of pond color and sky conditions, which is an advantage over recently developed radiometric retrieval methods.

We present the retrieval algorithm, including requirements to the data recording and survey planning, and a correction method for refraction at the air— pond interface. In addition, we show how the retrieved elevation model synergize with the initial image data to retrieve the water level of each individual pond from the visually determined pond exterior.

The study points out the great potential to derive geometric and radiometric properties of the sea-ice surface emerging from the increasingly available image data recorded from UAVs or aircraft.
The influence of atmosphere-ocean phenomenon on rainfall and streamflow variability across temperate Australia
Authors: Khaledi Jabbar , Nyman Petter , Nitschke Craig , Lane Patrick N.J , Penman Trent
Published: March 2021

Climate modes can have a large influence on the interannual variability in rainfall and streamflow.  Moreover, changes in their spatial-temporal patterns are likely to shape changes in hydroclimate in the future as a result of a warming climate. Modeling the links between climate modes, rainfall and streamflow is therefore important for understanding the trajectories in water availability. We examined the effects of four climate variability modes, El Nino Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), Southern Annular Mode (SAM), and Interdecadal Pacific Oscillation (IPO) on variations in annual rainfall and streamflow in four hydroclimate regions in temperate Australian. Climate mode indices, rainfall, and streamflow data from 1975 to 2018 were analyzed for 92 predominately forested catchments in four study regions. The annual variation and long-term fluctuations of rainfall and streamflow in each region were explored using the coefficient of variation, trend analysis, and random forest models to examine relationships to ENSO, IOD, SAM, and IPO. Coefficient of variation analysis showed that the annual variation of streamflow in and among catchments in each region was higher than rainfall. Rainfall and streamflow in each region were strongly influenced by different climate modes, and a higher proportion of variation in rainfall was explained by climate modes. Extreme annual rainfall and streamflow in these regions are related to concurrent phases of regional climate phenomena. These results provide critical baseline information and context for a better understanding of how future spatial and temporal changes in rainfall and streamflow across temperate Australia may manifest.
Numerical simulation of the dispersion of a sediment plume induced by seabed dredging in the northeastern tropical Pacific Ocean
Authors: Purkiani Kaveh , Gillard Benjamin , Paul André , Haeckel Matthias , Haalboom Sabine , Greinert Jens , de Stigter Henko , Hollstein Martina , Baeye Matthias , Vink Annemiek , Thomsen Laurenz , Schulz Michael
Published: March 2021

Prediction of the dispersion of sediment plumes induced by potential mining activities is still very limited due to operational limitations on in-situ observations required for a thorough validation and calibration of numerical models. Here we report on a plume dispersion experiment carried out in the German License Area for the exploration of polymetallic nodules in the northeastern tropical Pacific Ocean. The dispersion of a sediment plume induced by a dredging experiment in April 2019 was investigated by employing a hydrodynamic high-resolution regional ocean model coupled to a sediment transport module.

Various aspects including sediment characteristics and ocean hydrodynamics are examined to obtain the best statistical agreement between observation and model results. Results show that the model is capable to reproduce suspended sediment concentration and re-deposition patterns observed in the dredging experiment. Due to a strong southward current during the experiment, the model predicts no sediment deposition and plume dispersion north of the dredging tracks. The sediment re-deposition thickness reaches up to 9 mm at the dredging tracks and 0.01 mm at far-field at a distance of about 500 m from the dredging tracks.

The model results suggest that seabed topography and variable sediment release heights above the seafloor cause significant changes especially for the low sedimentation pattern in the far-field region due to different current regimes. The termination of seawater stratification can rise sediment plume above the seafloor and spread it in a larger vertical distances up to 10 m from the seafloor.
Paddle surfing for science on microplastic pollution: a successful citizen science initiative
Authors: Sanchez-Vidal Anna , Uviedo Oriol , Higueras Sara , Ballesteros Maria , Curto Xavier , de Haan William P. , Bonfill Elisabet , Canals Miquel , Canales Ingrid , Calafat Antoni , Comaposada Andrea , Del Río Paula , Ferrer Xavi , Fos Helena , Lastras Galderic , Llorente Martí , Martínez Ferran , Ramírez Martí , Pedrero Gines
Published: March 2021

Research on microplastics has rapidly expanded in recent years and has led to the discovery of vast amounts of microplastics floating offshore in all main oceanic gyres and including the Mediterranean Sea. However, there is a lack of information from a few meters from the coastline where the largest plastic mass flux is suspected to occur. The reason behind is the general use of manta trawls towed by boats or research vessels to obtain samples, which hinders nearshore sampling. We have designed a manta trawl to collect samples in the nearshore from any type of recreational sports floating gear like kayaks, sailboats, rowing boats, windsurf boards and others. Data generated is comparable to that obtained with traditional scientific equipment towed from boats. During one year, starting from October 2020, 12 social, environmental and sports associations along the NW Mediterranean coast are acquiring scientific samples in the nearshore within the frame of two citizen science monitoring projects lead by the Spanish delegation of the non-governmental organization Surfrider Foundation Europe and the University of Barcelona. The projects represent a paradigm shift in microplastic research, allowing to fill the gap in knowledge of this transition coastal area, and actively involving citizens in the generation of new monitoring data (https://surfingforscience.org/).

Our results reveal that densities of floating plastics in the nearshore along the NW Mediterranean coast are on average similar to those found offshore. However, we observe high variability due to meteorological and oceanographic conditions (i.e. the occurrence of eastern storms). We also observe that whereas floating microplastics dominate offshore, greater proportions of mesoplastics and macroplastics dominate at the nearshore waters, especially in between the breakwaters in Barcelona city. Indeed, the breakwaters, that protect Barcelona beaches against wave action and coastal erosion, behave as plastic traps. This is an indication of the importance of the nearshore as a source of plastic fragments to the open sea and calls for increased research in this area.
The development and relevance of a consistent flagging strategy for multi-sensor satellite soil moisture climate records
Authors: van der Vliet Mendy , de Jeu Richard , Rodriguez-Fernandez Nemesio , Scanlon Tracy , Colliander Andreas , Preimesberger Wolfgang , Dorigo Wouter , Madelon Rémi , van der Schalie Robin
Published: March 2021

The quality of soil moisture retrievals from passive microwave satellite sensors is limited during certain conditions, e.g. snow coverage, radio-frequency interference and dense vegetation. Therefore, masking the retrievals in these conditions by data flagging algorithms is vital for the production of reliable satellite-based products. However, these products utilise different flagging methods. A clear overview and comparison of these methods and their impact on the data are lacking. For long-term soil moisture records such as the ESA CCI soil moisture products, the impact of any flagging inconsistency from combining multiple sensor datasets was not assessed.

Recently, Van der Vliet et al. (2020) provided a review of the data flagging system that is used within multi-sensor ESA CCI soil moisture products as well as the flagging systems of two other soil moisture datasets from sensors that are also used for the ESA CCI soil moisture products: The level 3 Soil Moisture and Ocean Salinity (SMOS) and the Soil Moisture Active/Passive (SMAP). Substantial differences were detected between the SMOS and SMAP soil moisture flagging systems in terms of the number and type of conditions considered, critical flags, and data source dependencies. The impact on the data availability of the different flagging systems was shown to differ globally and especially for northern high latitudes, mountainous regions, and equatorial latitudes (up to 37%, 33%, and 32% respectively) with large seasonal variability. These results highlighted the relevance of a consistent and well-performing flagging approach that is applicable to all individual products used in long-term soil moisture data records.

Consequently, Van der Vliet et al. (2020) designed a consistent and model-independent flagging strategy to improve soil moisture climate records. For the snow cover, ice, and frozen conditions, which were found to have the highest impact on data availability, a uniform satellite driven flagging strategy was designed and evaluated against two ground observation networks. Compared to the individual flagging approaches adopted by the SMOS and SMAP soil moisture datasets, the new flagging approach was demonstrated to be a robust flagging alternative, with a similar performance, but with the applicability to the full ESA CCI historical record without the use of modelled approximations. 

A part of the designed flagging decision tree demonstrated to form a good base for the filtering of bare grounds and heavy precipitation events as well. A future extension of the flagging strategy is expected to mask these conditions, as well as other conditions such as radio frequency interference and dense vegetation.
Average Quantifying the snowmelt dominant river erosion in Afghanistan between 2004-2020
Authors: Mahmoodzada Abdul Basir , Varade Divyesh , Shimada Sawahiko , Okazawa Hiromu , Vinay Chembolu
Published: March 2021

Flooding of rivers is one of the major causes of soil erosion leading to significant changes in the geomorphological environment. Particularly, in countries such as Afghanistan, where the transboundary are designated according to the Amu River shorelines, are significantly affected by riverbank erosions. Amu River is driven by streamflow from the Pir Pranjal ranges of Afghanistan and Tajikistan. Numerical analysis of the river flow dynamics in such regions is subject to the scarce data availability on ground stations. Thus, ERA5 Reanalysis data provides a significant means for the temporal analysis of the geomorphological changes in such multi-national watersheds.

In this study, we propose a framework to quantify the Amu riverbank erosion in the Kaldar District of the Balkh Province of Afghanistan. The proposed framework is based on establishing an empirical relationship between the riverbank erosion area based on the discharge intensity and the specific stream power. To determine these two parameters, the river discharge is modeled using the ERA5 Reanalysis hydrological parameters based on multivariate regression. The river width is determined using the Normalized Difference Water Index-based (NDWI) derived from the Landsat-7 and Landsat-8 datasets. The riverbank erosion area is determined using shoreline analysis carried out using these datasets. The shoreline analysis indicates that Afghanistan is losing precious land due to the riverbank erosion over the past two decades (2004-20) amounting to as much as 86 sq. km and on average 5.4 sq. km every year. According to the ERA5 Reanalysis data, the water contribution from snowmelt in the spring and the summer was significantly dominant compared to the precipitation, which is consistent with several other watersheds in the north-western Himalayas. The river width and the discharge are observed to follow a power-law relation with an r2 of 0.7. Additionally, the discharge intensity and the specific stream power showed significant relation (r2 of 0.84 both) corresponding to the riverbank erosion area, where the peak flood events were observed to be outliers.
Assessment of landslide hazard in the province of Belluno (Veneto Region, Italy) before and after windstorm Vaia
Authors: Puliero Silvia , Arziliero Luciano , Bellotto Marianna , Catani Filippo , Floris Mario
Published: March 2021

In the last decades, extreme meteorological events, such as wind disturbances, have increased their frequency and their strength due to the effects of the climate changes and are expected to further intensify in the future. The strong winds combined with heavy rain modify the water-soil interaction and the soil mechanics raising the landslides hazard. An example of the damages caused by this atmospheric phenomenon is windstorm Vaia, that affected the north-eastern part of Italy in October 27th-30th, 2018. In particular, the province of Belluno (Veneto Region, Italy) was hit by intense rain and violent gusts of 150 km/h stripping 12,000 hectares of forests generating bare slopes. Several landslides occurred during and after the storm. The main aim of this research is to develop a multi-temporal geodatabase that allows to analyze the effects of critical extreme events on the landslide hazard. A spatial and multi-temporal landslide inventory is a crucial task to identify areas most prone to instability and to evaluate the variation of each conditioning factor over time, leading to an effective estimation of the hazard. In this work, the morphometric (elevation, slope, curvature) and the non-morphometric conditions (lithology, land use, distance to roads, distance to rivers), as well as the triggering factors of the instabilities occurred during and two years after the event have been considered and compared to the landslide-related factors before the windstorm. The instability phenomena occurred before the windstorm Vaia have been extracted from the Inventory of Landslide Phenomena in Italy (IFFI) carried out by the Italian Institute for Environmental Protection and Research (ISPRA) and the Regions and Autonomous Provinces. The landslides occurred during and after the meteorological event have been provided by the Veneto Region. The results show the variation in time of the instability scenario and the influence of the storm on the increase of landslide hazard. These outcomes can help to assess the temporal evolution of the slope dynamics after similar extreme climate contexts. In the future, thanks to the large availability of data obtained by direct site inspections in the area, we will validate remote sensing methods finalized to rapid landslide detection and characterization.
Verification of Mercator Ocean global ocean forecasts
Authors: Drévillon Marie , Regnier Charly , Sczcypta camille , Levier Bruno , Perruche Coralie , Van Gennip Simon
Published: March 2021

Mercator Ocean, based in Toulouse, France, provides operational oceanography services, and is entrusted by the European Commission to implement the Copernicus Marine Environment Monitoring Service CMEMS. As part of these services, Mercator Ocean develops and operates ocean analysis and forecasting systems based on the Ocean General Circulation Model NEMO, assimilating satellite and in situ observations of the Global Ocean Observing System. The global ocean 10-day forecasts are updated daily, and their horizontal resolution is 1/12° (~9km), which allows describing accurately the largest mesoscale features in the ocean. Biogeochemical Ocean forecasts are also produced, at a coarser resolution (~ 25km), providing information on large categories planktons and nutrients which are the first levels of the trophic chain in the ocean. The verification of these physical and biogeochemical forecasts is based on standards developed by the GODAE/Oceanpredict community, and by the CMEMS product quality working group. In this presentation, we will discuss the metrics which are used, and their representativeness depending on the variable and on the reference observations that are available.  In particular, recent results from the comparison of several forecast lengths with observed velocities will be shown.
The Effect of using a New Parameterization of Nucleation in the WRF-Chem model on the Cluster Formation Rate and Particle Number Concentration in a Passive Volcanic Plume
Authors: Arghavani Somayeh , Rose Clémence , Banson Sandra , Planche Céline , Sellegri Karine
Published: March 2021

Volcanic eruption is one of the main natural sources of atmospheric particles. In particular, evidence of New Particle Formation (NPF) from volcanic emission is reported in previous studies (Boulon et al., 2011; Sahyoun et al., 2019), which also suggests an essential role of sulfuric acid in this process. In addition, Rose et al. (2019) highlighted a significant contribution of the particles formed in the volcanic plume of the piton de la Fournaise to the budget of potential CCN at the Maïdo observatory, located ~40 km from the vent of the volcano. Therefore, it is predicted that the number and size of the cloud droplets, cloud growing and precipitation processes might be affected by the frequency of occurrence and characteristics of volcanically induced NPF in both local and regional scales, because volcanic plumes can extend far from the vent and even lower heights under the influence of the wind field and atmospheric dispersion. 

Following the study of Planche et al. (2020), the effect of using the New Parameterization of Nucleation (NPN) derived from the measurements performed in the passive volcanic emission plume of Etna (37.748˚ N, 14.99˚ E; Italy) (Sahyoun et al., 2019) in the WRF-Chem model (Weather Research and Forecasting Model coupled with Chemistry) is assessed, with a specific focus on the cluster formation rate and particle number concentration including CCN. In particular, results obtained with the NPN are compared to the predictions obtained with the default model settings, and further with observations.

In the next step, the resulting aerosol fields will be used to further evaluate the influence of the newly formed and grown particles on cloud formation and properties in a 3D cloud-scale model using a detailed microphysics scheme (DESCAM; Flossmann and Wobrock, 2010; Planche et al. 2010; 2014) . 
Silica formation in sorghum (Sorghum bicolor) roots
Authors: Zexer Nerya , Elbaum Rivka
Published: March 2021

Silicon oxides are the most abundant mineral group in soils. Therefore, plant roots are always exposed to some silicic acid (Si(OH)4), which is the soluble form of silicates. Monosilicic acid molecules are taken up by roots, carried in the xylem, and subsequently polymerize to silica in varied silicifying target sites. This biogenic silica (SiO2·nH2O) can constitute several percent by dry weight in certain plant taxa. However, the mechanisms of its formation remain mostly unknown. In the roots of sorghum (Sorghum bicolor), silica aggregates form in an orderly pattern along the cell walls of endodermis cells. To investigate the structure and composition of root silica aggregates, we studied their development along roots of hydroponically grown sorghum seedlings. By using Raman micro-spectroscopy, auto-fluorescence, and scanning electron microscopy, we found that putative silica aggregation loci could be identified in roots grown under Si starvation. These micrometer-scale spots were constructed of tightly packed modified lignin and were capable of nucleating trace concentrations of silicic acid. Substantial variation in cell wall auto-fluorescence between roots grown with and without silicic acid demonstrated the impact of silicon on cell wall chemistry. Taken together, this work demonstrates a high degree of control over lignin and silica deposition in cell walls. Such regulation implies an important, yet unknown, function for silicon in plant biology.
A coastal urban adaptation model with time-discounting, optimizing and satisficing decision making
Authors: Kovalevsky Dmitry , Scheffran Jürgen
Published: March 2021

We develop a discrete-time coastal urban adaptation model where the ‘present’ and ‘future’ time periods are distinguished. In the model, the city anticipates sea level rise and related coastal hazards with adverse impacts on urban economy in the future period. However, the magnitude of future sea level rise and induced climate damages are known with uncertainty. The urban planning agent has to make at present a decision on how much to invest in climate adaptation (in the form of construction of coastal protection). We explore three complementary models of decision making. They include the intertemporal maximization of time-discounted expected utility of consumption and two versions of the VIABLE modelling framework with an optimizing and a satisficing urban planning agent, respectively. It is shown that in certain model setups, investment decisions depend discontinuously on the value of key model parameters. In particular, when these parameters are varied, the urban planner can discontinuously switch from the ‘business-as-usual’ (BaU) strategy, when no adaptation investment is taken, to a proactive adaptation.
Accounting for Seasonality in Extreme Sea Level Estimation
Authors: D'Arcy Eleanor
Published: March 2021

Storm surges pose an increasing risk to coastline communities. These events, combined with high tide, can result in coastal flooding. To reduce the impact of storm surges, an accurate estimate of coastal flood risk is necessary. Specifically, estimates are required for the return level of sea levels (still water), which is the level with annual exceedance probability p. This estimate is used as an input to determine the height for a coastal defence, such as a sea wall. The return level estimation requires statistical analysis based on extreme value theory, as we need to know about the frequency of events that are more extreme than those previously observed.

Large storm surges exhibit seasonality, they are typically at their worst in the winter and least extreme in the summer. This seasonal pattern differs from that of the tide, whose seasonality is driven astronomically, resulting in tidal peaks at the spring and autumn equinoxes. Hence, the worst levels of these two components of still water level are likely to peak at different times in the year, and so statistical methods that treat them as independent variables are likely to over-estimate return levels.

We focus on the skew surge: the difference between the observed and predicted high water within a tidal cycle. Williams et al. (2016) show that tide and skew surge are independent conditional on the time of year. Batstone et al. (2013) used this property to derive estimates used for UK coastal flood defences. They used generalised Pareto distributions for the skew surge tail but did not account for the separate seasonality of tide and skew surge.

This work aims to model how the distribution of skew surges changes over a year and we combine our results with the known seasonality of tides to derive estimates of still water level return levels. We compare our results with the Batstone et al. (2013) approach at a few locations on the UK coastline.

References:

Batstone, C., Lawless, M., Tawn, J., Horsburgh, K., Blackman, D., McMillan, A., Worth, D., Laeger, S. and Hunt, T., 2013. A UK best-practice approach for extreme sea-level analysis along complex topographic coastlines. Ocean Engineering, 71, pp.28-39.

Williams, J., Horsburgh, K.J., Williams, J.A. and Proctor, R.N., 2016. Tide and skew surge independence: New insights for flood risk. Geophysical Research Letters, 43(12), pp.6410-6417.
InSAR, seismic noise, and geotechnical data to assess landslide activity and geometry: the Villa de Independencia (Cochabamba, Bolivia) case study
Authors: Pazzi Veronica , Del Soldato Matteo , Song Chuang , Yu Chen , Li Zhenhong , Cruz Abel , Utili Stefano
Published: March 2021

Interferometric Synthetic Aperture Radar (InSAR) enables detailed investigation of surface landslide movements but lacks information about subsurface recognition/identification. It can be obtained by means of direct measurements (e.g., geotechnical data) and geophysical techniques. InSAR observations, seismic noise measurements, and geotechnical data were integrated to assess the deformation on the ground surface and to determine the depth of the failure surface of the Villa de Independencia landslide, Cochabamba (Bolivia) affecting the village. It is a compound slow-moving landslide (total area approximatively 3.8·106 m2) composed by three sub-blocks slide exhibiting diverse geometries, multiple failure surfaces, and magnitudes.

For investigating the spatiotemporal characteristics of the landslide motion, Sentinel-1 time series from October 2014 to December 2019 were analysed. A new geometric inversion method was also proposed to determine the best-fit sliding direction and inclination of the landslide. Results of the Sentinel-1 time series show two substantial accelerations in early 2018 and 2019, coinciding with an increment of precipitations in the late rainy season. It allows supposing the rainy as the most likely triggers of the identified accelerations.

The seismic noise measurements (more than one hundred spreaded over the whole landslide), analysed according to the Vertical to Horizontal Spectral Ratio technique (H/V), were calibrated and validated by means of the geotechnical data derived by three boreholes and 13 between rock and soil samples. H/V data allowed identifying the different dynamic characteristics of the three sub-blocks: movements are possibly due to the different properties of shallow and deep slip surfaces. The landslides caused damage on the edifices, probably mainly caused by the shallow slip interface (located at a mean depth of 5 m) since the foundation depth of the buildings is at most 2 m. In the town centre a deeper failure surfaces, approximatively with depth between 15 and 75 m, can be identified which may be responsible for its different direction and acceleration magnitude of sliding (inferred by InSAR) compared to the other parts of the landslides. Finally, the determination of the slip surface depths allowed to estimate the overall landslide volume assessed approximatively 9.18·107 m3.

The study shows the great potential for landslide motion characterization and mechanism investigation by combing InSAR, seismic noise and geotechnical measurements.
Corner Reflector Network as a Geodetic Reference for Landslide Monitoring via InSAR Time Series: Case Study from Slovakia
Authors: Czikhardt Richard , Papco Juraj , Ondrejka Peter , Ondrus Peter , Liscak Pavel
Published: March 2021

SAR interferometry (InSAR) is inherently a relative geodetic technique requiring one temporal and one spatial reference to obtain the datum-free estimates on millimetre-level displacements within the network of radar scatterers. To correct the systematic errors, such as the varying atmospheric delay, and solve the phase ambiguities, it relies on the first-order estimation network of coherent point scatterers (PS).

For vegetated and sparsely urbanized areas, commonly affected by landslides in Slovakia, it is often difficult to construct a reliable first-order estimation network, as they lack the PS. Purposedly deploying corner reflectors (CR) at such areas strengthens the estimation network and, if these CR are collocated with a Global Navigation Satellite Systems (GNSS), they provide an absolute geodetic reference to a well-defined terrestrial reference frame (TRF), as well as independent quality control.

For landslides, line-of-sight (LOS) InSAR displacements can be difficult to interpret. Using double CR, i.e. two reflectors for ascending/descending geometries within a single instrument, enables the assumption-less decomposition of the observed cross-track LOS displacements into the vertical and the horizontal displacement components.

In this study, we perform InSAR analysis on the one-year of Sentinel-1 time series of five areas in Slovakia, affected by landslides. 24 double back-flipped trihedral CR were carefully deployed at these sites to form a reference network, guaranteeing reliable displacement information over the critical landslide zones. To confirm the measurement quality, we show that the temporal average Signal-to-Clutter Ratio (SCR) of the CR is better than 20 dB. The observed CR motions in vertical and east-west directions vary from several millimetres up to 3 centimetres, with average standard deviation better than 0.5 mm.
Repeated GNSS measurements of the CR confirm the displacement observed by the InSAR, improve the positioning precision of the nearby PS, and attain the transformation into the national TRF.