bluuebunny/crossref_metadata_2025 huggingface dataset:
ИЗУЧЕНИЕ ФЛУКТУИРУЮЩЕЙ АСИММЕТРИИ КАК ФАКТОРА СТОХАСТИЧЕСКОГО ПРОЯВЛЕНИЯ ЭПИГЕНЕТИЧЕСКИХ ПРОЦЕССОВ У ВОДНЫХ ОБЪЕКТОВ
Authors: Григоренко Анастасия , Кураченко Ирина
Published: March 2021

В данной работе был произведен анализ влияния различных факторов на отклонения состояния организма от условной нормы по величине интегрального показателя стабильности развития между различными таксономическими классами, с целью доказательства корреляции между представителями батрахофауны и ихтиофауны при изучении флуктуирующей асимметрии как феномена фенотипической изменчивости, при помощи пятибалльной шкалы оценки влияния антропогенного загрязнения на билатеральные признаки и дисперсионного анализа. Новизна исследования заключается в том, что при изучении водных объектов, находящихся на одной территории, можно утверждать о взаимосвязи их показателей, исключая значимость различных таксономических групп в отдельности, тем самым давая возможность сократить использование малочисленных видов в качестве биоиндикаторов при массовых исследованиях, ошибочно предполагая их наиболее выгодными объектами для изучения, тем самым избегая элиминации и сохраняя аквакультуру.
WAYS TO INCREASE PRODUCTIVITY ON THE ERODED LANDS IN LANKARAN
Authors: Akbarova Ulkar
Published: March 2021

Reasons of the water erosion creation in the Lankaran province and their complications have been investigated in this article. An influence of the water erosion on agrochemical and agrophysical indicators of the soil was learnt, it was known that the granulometric composition and even a quantity of humus and total nitrogen significantly deteriorated. Considering this, the proposals were put forward for protection and enhancement of the soil fertility exposed to water erosion.
A comparative study of Distributed Large Scale Data Mining Algorithms
Authors: Sood Isha , Sharma Varsha
Published: March 2021

Essentially, data mining concerns the computation of data and the identification of patterns and trends in the information so that we might decide or judge. Data mining concepts have been in use for years, but with the emergence of big data, they are even more common. In particular, the scalable mining of such large data sets is a difficult issue that has attached several recent findings. A few of these recent works use the MapReduce methodology to construct data mining models across the data set. In this article, we examine current approaches to large-scale data mining and compare their output to the MapReduce model. Based on our research, a system for data mining that combines MapReduce and sampling is implemented and addressed
Development of IoT based solution for monitoring & controlling of loads using Google Assistant with Home Security System
Authors: Rahiman M. Abdul , Manohar D
Published: March 2021

The main aim of this project is to make a cost effective device which is used to monitor and control the loads by using simple voice commands. Previously we have ALEXA, SIRI & GOOGLE HOME which makes us more expensive. Even now when technology is handy enough only the well to do people of the society are blessed with these new smart home devices, as these devices costs are a bit high. However, not everyone is wealthy enough to be able to afford a human assistant, or some smart home kit. Hence, the need for finding an inexpensive and smart assistant for normal families keeps growing. This project proposes such inexpensive system. It uses the Google Assistant, the IFTTT application, the remoteme.org cloud application and the NodeMCU microcontroller as the major components along with a relay board comprising of 4 relays along with different sensors are working in this. Natural language voice is used to give
commands to the Google Assistant All of the components are connected over the internet using Wi-Fi which puts this system under the IoT. And also we monitor data in this that is we using the different sensors like IR sensors, LDR (Light Emitting Diode) sensors etc; Not only to monitor and control the Loads but also providing the Security System to the Home, whenever the thief or the visitor enter into the room the owners will get push notification in their smart phone and also capturing the photos of visitors and uploaded to the Google Drive.
Implementasi Compatibility Layer Pada Jaringan Server Diskless Berbasis Lubuntu 18.04 LTS
Authors: Farid Jatri Abiyyu  , Ibnu Ziad  , Ade Silvia Handayani
Published: March 2021

Diskless server is a cluster computer network which uses SSH (Secure Shell) protocol to grant the client an access to the host's directory and modify it's content so that the client don't need a hardisk (Thin Client). One way to design a diskless server is by utilizing "Linux Terminal Server Project", an open source-based script for Linux. However, using Linux has it own drawback, such as it can't cross platform for running an aplication based on Windows system which are commonly used. This drawback can be overcomed by using a compatibility layer that converts a windows-based application's source code. The data which will be monitored is the compatibility layer implementation's result, and the throughput, packet loss, delay, and jitter. The result of measurement from those four parameters resulting in "Excellent" for throughput, "Perfect" for packet loss and delay, and "Good" for jitter.
Model based assessment of drift and fate of marine micro plastics in the Baltic Sea
Authors: Murawski Jens , She Jun , Frishfelds Vilnis
Published: March 2021

Marine micro plastic is a growing problem, because of its ability to accumulate in the environment. Reliable data of drift patterns and accumulation zones are required to estimate environmental impacts on natural protected areas, spawning areas and vulnerable habitats. H2020 project CLAIM (Cleaning Litter by developing and Applying Innovative Methods) uses model based assessments to improve the knowledge on marine pathways, sources and sinks of land emitted plastic pollution. The assessment follows a systematic approach, to derive reliable emission values for coastal sources, and to model drift and deposition pattern of micro plastics from multiple sources: car tyres, cosmetic products. A 3D modelling tool has been developed, that includes all relevant key processes, i.e. currents and wave induced transport, biofilm growth on the particle surface, sinking and sedimentation. Core engine is the HBM ocean circulation model, which has been set-up for the Baltic Sea in high resolution of 900m. Multi-years-studies (2013-2019) were performed to evaluate seasonal drift pattern and accumulation zones. Highest micro plastic concentrations were found in coastal waters, near major release locations, but transport related offshore pattern can be found as well. These follow the major pathways of deeper sea transport, but are controlled by the seasonal dynamic of biofilm growth and sinking. We introduce the model and all relevant key processes. Seasonal drift pattern are discusses in detail. Validation results in the Gulf of Riga and the Gulf of Finland provide an overview of the quality of the model to predict the distribution of micro plastics. The study includes the assessment of mitigation scenarios, of 30% micro plastic load reductions. The impacts on the ocean levels of micro plastic concentrations are studied in detail.  

 

 
Effects of heterogeneity on frictional-viscous deformation and the depth-extent of the seismogenic zone
Authors: Fagereng Ake , Beall Adam
Published: March 2021

Current conceptual fault models define a seismogenic zone, where earthquakes nucleate, characterised by velocity-weakening fault rocks in a dominantly frictional regime. The base of the seismogenic zone is commonly inferred to coincide with a thermally controlled onset of velocity-strengthening slip or distributed viscous deformation. The top of the seismogenic zone may be determined by low-temperature diagenetic processes and the state of consolidation and alteration. Overall, the seismogenic zone is therefore described as bounded by transitions in frictional and rheological properties. These properties are relatively well-determined for monomineralic systems and simple, planar geometries; but, many exceptions, including deep earthquakes, slow slip, and shallow creep, imply processes involving compositional, structural, or environmental heterogeneities. We explore how such heterogeneities may alter the extent of the seismogenic zone.

 

We consider mixed viscous-frictional deformation and suggest a simple rule of thumb to estimate the role of heterogeneities by a combination of the viscosity contrast within the fault, and the ratio between the bulk shear stress and the yield strength of the strongest fault zone component. In this model, slip behaviour can change dynamically in response to stress and strength variations with depth and time. We quantify the model numerically, and illustrate the idea with a few field-based examples: 1) earthquakes within the viscous regime, deeper than the thermally-controlled seismogenic zone, can be triggered by an increase in the ratio of shear stress to yield strength, either by increased fluid pressure or increased local stress; 2) there is commonly a depth range of transitional behaviour at the base of the seismogenic zone – the thickness of this zone increases markedly with increased viscosity contrast within the fault zone; and 3) fault zone weakening by phyllosilicate growth and foliation development increases viscosity ratio and decreases bulk shear stress, leading to efficient, stable, fault zone creep. These examples are not new interpretations or observations, but given the substantial complexity of heterogeneous fault zones, we suggest that a simplified, conceptual model based on basic strength and stress parameters is useful in describing and assessing the effect of heterogeneities on fault slip behaviour.         
Cereal yield forecasting in Morocco using the CARAIB dynamic vegetation model driven by HadGEM2-AO projections
Authors: Loudiyi Iliass , Jacqemin Ingrid , Tychon Bernard , François Louis , Lahlou Mouanis , Wellens Joost , Balaghi Riad
Published: March 2021

Food security, in Morocco as in many parts of the world, depends heavily on cereal production which fluctuates relying on weather conditions. In fact, Morocco has a production system for cereals which is dominated by rainfed. It is therefore necessary to further develop knowledge about climate change and strengthen forecasting systems for predicting the impacts of climate change.

Our research, funded by a bilateral project of Wallonie-Bruxelles International, aims to study the response of cereal production to climate change, using the dynamic vegetation model CARAIB (CARbon Assimilation In the Biosphere) developed within the Unit for Modelling of Climate and Biogeochemical Cycles (UMCCB) of the University of Liège. This spatial model includes crops and natural vegetation and may react dynamically to land use changes. Originally constructed to study vegetation dynamics and carbon cycle, it includes coupled hydrological, biogeochemical, biogeographical and fire modules. These modules respectively describe the exchange of water between the atmosphere, the soil and the vegetation, the photosynthetic production and the evolution of carbon stocks and fluxes in this vegetation-soil system. For crops, a specific module describes basic management parameters (sowing, harvest, rotation) and phenological phases.

The simulations are performed across all Morocco using different input data. The three main cereal crops simulated include soft wheat, durum wheat and barley, they are grown in all provinces and all agro-ecological zones. Regarding climatic inputs, we’re using two sets of data: the first one is interpolated and bias-corrected fields from the climate model HadGEM2-AO for the historical period (1990-2005), in addition to three different Representative Concentration Pathway scenarios (RCP2.6, RCP4.5 and RCP8.5) from 2005 to 2100. The second one is high resolution (30 arc sec) gridded climate data derived from WorldClim combined with interpolated anomalies from CRU (Climatic Research Unit) over the historical period 1990 to 2018.

After obtaining preliminary results for the past period, and in order to improve the prediction using the field data which are the observed yields, we performed a sensitivity analysis. We used the One-at-a-time (OAT) approach by moving one input variable, keeping others at their baseline (nominal) values, then, returning the variable to its nominal value, then repeating for each of the other inputs in the same way. Sensitivity may then be measured by monitoring changes in the output, using linear regression. The inputs studied are the initial value of carbon pool, leaf C/N ratio, water stress, sowing date, GDD harvest, stomatal conductance parameters, specific leaf area, and rooting depth.
Synoptic view on sub-ionospheric VLF/LF amplitude and phase variations at the Graz seismo-electromagnetic facility
Authors: Eichelberger Hans , Schwingenschuh Konrad , Boudjada Mohammed Y. , Besser Bruno P. , Wolbang Daniel , Solovieva Maria , Biagi Pier F. , Stachel Manfred , Aydogar Özer , Pitterle Martin , Muck Cosima , Grill Claudia , Jernej Irmgard
Published: March 2021

This presentation discusses physical processes related to potentially seismic and non-seismic disturbances along VLF/LF paths measured with two different receivers located side by side at the Space Research Institute (IWF) facility in Graz, Austria. At the same time both systems are embedded in international networks which gives the unique opportunity to probe the waveguide cavity over a large area.
In general, a variety of VLF/LF amplitude and phase variations are ubiquitous at wide scales throughout the cavity. We analyse such signals observed in the period 2018-2020 (solar minimum, i.e. less external forcing of the upper ionospheric boundary) in the time- and frequency-domain for several paths. In this attempt we aim to single out natural disturbances, characterise the source event, and figure out the lithosphere-atmosphere-ionosphere coupling mechanism. For known seismic events we consider the so-called Dobrovolsky-Bowman relationship [1,2] allowing to estimate the pre-seismic zone crossed by the VLF/LF paths.
The findings open up good prospects for an automated monitoring and characterisation of source phenomena who affect the electric field of VLF/LF sub-ionospheric links.

Ref:
[1] Dobrovolsky, I.P., Zubkov, S.I., and Miachkin, V.I., Estimation of the size of earthquake preparation zones, PAGEOPH 117, 1025–1044, 1979.
https://doi.org/10.1007/BF00876083
[2] Bowman, D.D., Ouillon, G., Sammis, C.G., Sornette, A., and Sornette, D., An observational test of the critical earthquake concept, JGR Solid
Earth, 103, B10, 24359-24372, 1998. https://doi.org/10.1029/98JB00792
Diagenetic complexities of iron oxide cements in Mesozoic sandstones of Utah, U.S.A.
Authors: Potter-McIntyre Sally , Chan Marjorie
Published: March 2021

Stratigraphic units of the Colorado Plateau comprise a remarkable Mesozoic section in Utah. Thse units are ideal for studying sandstone diagenesis where there is established basinal context of depositional facies and tectonics, as well as continuity of exposure. To untangle the complex relationships and diagenetic histories, it is crucial to understand host rock properities (porosity and permeability), authigenic mineralogies (that give clues to fluid composition), diagenetic textures, and age dating. This study is a review and synthesis of previous work that has contributed to the understanding of the diagenetic history recorded in authigenic iron oxide precipitates. We discuss cement generations and mineralogies, fluid chemistries, origins and mobilization of iron, and timing of precipitation. Spheroidal cemented mineral masses (concretions) are common within many Mesozoic units of Utah – most notably the Jurassic Navajo Sandstone.  However, formation of these concretions is still not completely understood. Spheroidal concretions are currently a “hot topic”, especially since the discovery of similar “blueberry” features on Mars with their implications for habitability, and the potential for these nodules to host biosignatures. Several models for spheroidal concretion formation are evaluated. Understanding how iron is mobilized and precipitated and how spheroidal concretions form have implications for similar geometries and mineralogies in many terrestrial regions, but will require continued integrated studies across multiple scales (see Baker and Potter-McIntyre, this session). These scales include the submicroscopic levels of understanding and detecting the potential role of microbes in mineral precipitation, to the larger scale mapping of regional diagenetic coloration and mineral patterns that could represent records of basinal fluids and the response to climate, tectonics, and regional hydrology.
Climatology of low wind and solar power production events in Europe with Grosswetterlagen classification
Authors: Ho Linh , Fiedler Stephanie
Published: March 2021

Low production of renewable energy for up to several days can cause stress on the electricity system, especially when such events coincide with high demand. Meteorological conditions leading to extremely low production of wind and PV power are known. These are periods of relatively little irradiance and anomalously weak winds. Past work underlined the importance of high-pressure systems over Central Europe during winter for causing such conditions. However, there is less known about low-production periods in other seasons and their regional scale characteristics from a climatological perspective. Despite being probably less severe in summer, low-production events can nevertheless be problematic. One example is the higher electricity demand for cooling systems in summer, which is especially relevant in the context of climate change.

Here we statistically analyse the synoptic meteorological conditions causing low-production events of wind and solar power in Europe for winter and summer. To this end, we use a daily weather regime classification for Europe from the German Weather Service, known as “Grosswetterlagen” (GWL). Our simulation of the production of wind and PV power is based on the reanalysis data COSMO-REA6 for Europe with a horizontal resolution of 6 km, and an established wind and PV power model, developed in the research area “Climate Monitoring and Diagnostics” of the Hans-Ertel Centre for Weather Research. Scenarios of gridded installed capacity of PV and wind power plants in Europe for 2050 are taken from the CLIMIX model to calculate hourly power production. Our composite analysis of the PV and wind power production associated with the different GWLs highlight (1) the regional differences in the power production in Europe across country borders and (2) different regional patterns of anomalies in power production depending on  GWLs. Based on our simulations, we derive an atlas of potential PV and wind production associated with different GWLs. This atlas will be helpful to understand which GWLs lead to regionally low-production events, and to what extend the severity of such events can be forecasted in different seasons. Such knowledge is important since the share of wind and solar power continues to increase in the European electricity grid.
A novel agricultural drought monitoring framework using remote sensing products
Authors: Satapathy Trupti , Ramadas Meenu , Dietrich Jörg
Published: March 2021

Among natural hazards, droughts are known to be very complex and disastrous owing to their creeping nature and widespread impacts. Specifically, the occurrence of agricultural droughts poses a threat to the productivity and socio-economic development of countries such as India. In this study, we propose a novel framework for agricultural drought monitoring integrating the different indicators of vegetation health, crop water stress and soil moisture, that are derived from remote sensing satellite data. The drought monitoring is performed over Odisha, India, for the period 2000-2019. Soil moisture and land surface temperature datasets from GLDAS Noah Land Surface Model and surface reflectance data from MODIS (MOD09GA) are used in this study. We compared the utility of popular indices: (i) soil moisture condition index, soil moisture deficit index and soil wetness deficit index to represent the soil moisture level; (ii) temperature condition index, vegetation condition index and normalised difference water index to indicate vegetation health; (iii) short wave infrared water stress to represent crop water stress condition. Correlation analyses between these indices and the seasonal crop yields are performed, and suitable indicators are chosen. The popular entropy weight method is then used to integrate the indices and develop the proposed composite drought index. The index is then used for monitoring the agricultural drought condition over the study area in drought periods. The proposed framework for week- to month-scale monitoring have potential applications in identification of agricultural drought hotspots, analysis of trends in drought severity, and drought early warning for agricultural water management.
The corundum conundrum: Constraining the compositions of fluids involved in metasomatic corundum formation.
Authors: van Hinsberg Vincent , Yakymchuk Chris , Kirkland Christopher , Szilas Kristoffer
Published: March 2021

Corundum, including the variety ruby, is found in numerous locations in the Archaean North Atlantic Craton of southern Greenland. Corundum owes its occurrence to fluid-induced interaction among high-grade metamorphic lithologies of contrasting chemistry. Here, we present constraints on the conditions of corundum formation and the compositions of the fluids involved for the Storø and Maniitsoq ruby localities. We use thermodynamic modelling of mineral and mineral-fluid equilibria, and complement these with experimentally obtained data on mineral solubility to show that metasomatism took place at 650-725˚C and 7 kbar, involving a boron-rich, acidic fluid of low fO2 and low X(CO2). Aqueous concentrations of aluminium are low and indicate that corundum saturation is the result of residual aluminium enrichment rather than aluminium mobilisation. Intrusion of the ca. 2.55 Ga Qôrqut granite and associated fluid release is the likely source of boron, and U-Pb dating of rutile inclusions is consistent with a temporal link between ruby formation and granite emplacement. Interaction with meta-dunite and Fe-sulfides modified the oxidized magmatic fluid, introduced SO4, and produced the reduced, high XMg and K-rich fluid recorded by the corundum-bearing samples. These results highlight a complex interplay among lithologies involved in corundum-formation, but also demonstrate that corundum formation is a predictable part of the geological history where a magmatic intrusion expels a pulse of fluid through its lithologically heterogeneous carapace.
3D Models for web based climate education 
Authors: Sumners Ronald , Vargas Suarez Luisa , Griffiths Jamie , Donev Jason
Published: March 2021

Effectively informing the public about anthropogenically accelerated climate change and sustainable energy is one of the most immense challenges of our age. However, web-based 3D environments are cost-effective, accessible tools that can combat many of the challenges associated with global outreach, especially during the COVID-19 pandemic. This presentation explores how 3D CAD modeling, visual texturing, Three.JS (a WebGL rendering software), and web design can coexist to create effective tools for educators across the world. By applying these simulations, learners are able to examine individual components of objects and break down complex systems into their fundamental parts for simpler understanding. Moreover, by breaking down these systems, individuals are able to more effectively understand the complex physical phenomena that drive our world. In addition, these environments are not limited by topic or language and therefore the spectrum to which we can apply these ideas is not limited. Translating the simulations is relatively straightforward and with the expertise of individuals who can lead this front, the reach of this type of technology can grow even wider. Climate change is a global issue and so work in the field must be addressed as such as well. As a result, these models have the ability to transform the way we learn about global issues and can be a powerful tool in education about sustainable energy, climate change and science in general.
Impacts of climatic changes on fluvial sediment fluxes in north western Europe: The Middle and Late Pleistocene Meuse river system
Authors: da Silva Guimarães Ewerton , van Balen Ronald T. , Kasse Cornelis , Busschers Freek S. , Bouroullec Renaud
Published: March 2021

Climate change and tectonics can generate signals in a source-to-sink system in the form of changing sediment supply. The study of the propagation of this signal through the system might elucidate how different source-to-sink systems respond to a given perturbation, for instance, the Early to Middle-Pleistocene climate transition. Knowledge on the temporal and spatial responses to such perturbations in a catchment is still limited. Previous studies, with the support of landscape evolution models, demonstrate that several thousands of years might be needed for an extreme-climate-transition-induced signal to propagate through a river catchment (an example of source-to-sink system). The present work aims to contribute to the understanding of how such systems might react when submitted to rapid climate change events by studying the Meuse river catchment. The primary goals are to characterize and quantify the main controls on sediment flux of this fluvial system as a response to the Early to Middle Pleistocene climate transition as well as to assess how climate signals propagated through this source-to-sink system during the last four glacial-interglacial cycles, starting around 450.000 years ago.

To achieve our goals, three main tasks are proposed. In the first stage of this project, with the support of high-resolution DEM and high-resolution sedimentary cores, the different Meuse fluvial terrace maps are updated. For that, a new cross-border fluvial terrace map between the Netherlands, Belgium and Germany is produced. Characterization and mapping of sediment grain-size and provenance is also carried out. The new Meuse terrace map will guide the sampling campaign of Meuse terrace sediments. The samples will be used for cosmogenic-nuclide age-dating of the sampled terraces. Two dating methods will be used depending on how deeply buried and well-preserved the terraces are: burial isochrone (26Al/10Be) where sediment cover thickness is greater than 4,5 – 5 m, and depth profile (10Be) when the terrace surface is well preserved. These methods will be applied to specific terrace steps, in order to date those around the Mid-Pleistocene transition. Beryllium-10 age-dating will possibly also be applied to specific sedimentary levels (cores, outcrops), in order to infer averaged denudation rates and, consequently, the sediment fluxes, during the investigated climatic cycles. During the latter part of the project, all the data will be set in a temporal framework using the cosmogenic dating results and existing age controls.
Secondary ice production in NorESM2 climate model: quantifying the impact on Arctic clouds
Authors: Sotiropoulou Georgia , Lewinschal Anna , Ekman Annica , Nenes Athanasios
Published: March 2021

Arctic clouds are among the largest sources of uncertainty in predictions of Arctic weather and climate. This is mainly due to errors in the representation of the cloud thermodynamic phase and the associated radiative impacts, which largely depends on the parameterization of cloud microphysical processes. Secondary ice processes (SIP) are among the microphysical processes that are poorly represented, or completely absent, in climate models. In most models, including the Norwegian Earth System Model -version 2 (NorESM2), Hallet-Mossop (H-M) is the only SIP mechanism available. In this study we further improve the description of H-M and include two additional SIP mechanisms (collisional break-up and drop-shattering) in NorESM2. Our results indicate that these additions improve the agreement between observed and modeled ice crystal number concentrations and liquid water path in mixed-phase clouds observed at Ny-Alesund in 2016-2017. We then conclude by quantifying the impact of these overlooked SIP mechanisms for cloud microphysical characteristics, properties and the radiative balance throughout the Arctic.

 
The CME arrival prediction with the Effective Acceleration Model: Further testing with heliospheric imaging observations
Authors: Paouris Evangelos , Vourlidas Angelos , Papaioannou Athanasios , Anastasiadis Anastasios
Published: March 2021

The estimation of the Coronal Mass Ejection (CME) arrival is an open issue in the field of Space Weather. Many models have been developed to predict Time-of-Arrival (ToA). In this work, we utilize an updated version of the Effective Acceleration Model (EAM) to calculate the ToA. The EAM predicts the ToA of the CME-driven shock and the sheath's average speed at 1 AU. The model assumes that the interaction between the ambient solar wind and the interplanetary CME (ICME) results in constant acceleration or deceleration. We recently compared EAM against ENLIL and drag based models (DBEM) with a sample of 16 CMEs. We confirmed the well-known fact that the deceleration of fast ICMEs in the interplanetary medium is not captured by most models. We study further the deceleration of fast ICMEs by introducing, for the first time, wide-angle observations by the STEREO heliospheric imagers into the EAM model. The speed profiles for some test cases show deceleration in the interplanetary medium at greater distances compared with the field-of-view of the coronagraphs.
The Global Heat Flow Database: a collaborative and fundamental revision process to ensure comprehensible and reliable heat-flow records
Authors: Fuchs Sven , Beardsmore Graeme , Chiozzi Paolo , Espinoza-Ojeda Orlando Miguel , Gola Gianluca , Gosnold Will , Harris Robert , Jennings Sam , Liu 'Shaowen , Negrete-Aranda Raquel , Neumann Florian , Norden Ben , Poort Jeffrey , Rajver Dušan , Ray Labani , Richards Maria , Smith Jared , Tanaka Akiko , Verdoya Massimo
Published: March 2021

The compilation of global heat-flow data is currently under major revision by the International Heat Flow Commission (IHFC) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI). Heat flow represents a fundamental parameter in thermal studies, e.g., the evolution of hydrocarbons or mineral and geothermal resources. Comparable, comprehensible and reliable heat-flow data are of utmost interest also for geophysical and geological studies on the global scale. Here, we present the first results of a stepwise revision of the IHFC Global Heat Flow Database based on a researcher driven, collaborative approach. The first step comprises the review and revision of the most recent database structure established in 1976. The revised structure of the Global Heat Flow Database considers the demands and opportunities presented by the evolution of scientific work, digitization and the breakthroughs in database technologies over the past decades.  Based on the new structure, the existing dataset will be re-assessed and new data incorporated. By supporting the ideas of FAIR and open data principles, the new database facilitates interoperability with external data services, like DOI and IGSN numbers, and other data resources (e.g., world geological map, world stratigraphic system, and International Ocean Drilling Program data). We give an overview of the new database and introduce the community workflow of global heat-flow data revision.
Influence of in-cloud oxidation of organic compounds on tropospheric ozone
Authors: Rosanka Simon , Sander Rolf , Franco Bruno , Wespes Catherine , Wahner Andreas , Taraborrelli Domenico
Published: March 2021

Large parts of the troposphere are affected by clouds, whose aqueous-phase chemistry differs significantly from gas-phase chemistry. Box-model studies have demonstrated that clouds influence the tropospheric oxidation capacity. However, most global atmospheric models do not represent this chemistry reasonably well and are largely limited to sulfur oxidation. Therefore, we have developed the Jülich Aqueous-phase Mechanism of Organic Chemistry (JAMOC), making a detailed in-cloud oxidation model of oxygenated volatile organic compounds (OVOCs) readily available for box as well as for regional and global simulations that are affordable with modern supercomputers. JAMOC includes the phase transfer of species containing up to ten carbon atoms, and the aqueous-phase reactions of a selection of species containing up to four carbon atoms, e.g., ethanol, acetaldehyde, glyoxal. The impact of in-cloud chemistry on tropospheric composition is assessed on a regional and global scale by performing a combination of box-model studies using the Chemistry As A Boxmodel Application (CAABA) and the global atmospheric model ECHAM/MESSy (EMAC). These models are capable to represent the described processes explicitly and integrate the corresponding ODE system with a Rosenbrock solver. 

Overall, the explicit in-cloud oxidation leads to a reduction of predicted OVOCs levels. By comparing EMAC's prediction of methanol abundance to spaceborne retrievals from the Infrared Atmospheric Sounding Interferometer (IASI), a reduction in EMAC's overestimation is observed in the tropics. Further, the in-cloud OVOC oxidation shifts the hydroperoxyl radicals (HO2) production from the gas- to the aqueous-phase. As a result, the in-cloud destruction (scavenging) of ozone (O3) by the superoxide anion (O2-) is enhanced and accompanied by a reduction in both sources and sinks of tropospheric O3 in the gas phase. By considering only the in-cloud sulfur oxidation by O3, about 13 Tg a-1 of O3 are scavenged, which increases to 336 Tg a-1 when JAMOC is used. With the full oxidation scheme, the highest O3 reduction of 12 % is predicted in the upper troposphere/lower stratosphere (UTLS). Based on the IASI O3 retrievals, it is demonstrated that these changes in the free troposphere significantly reduce the modelled tropospheric O3 columns, which are known to be generally overestimated by global atmospheric models. Finally, the relevance of aqueous-phase oxidation of organics for ozone in hazy polluted regions will be presented.  
Fluctuating Lake Levels in Rift Basins and its Impact on Extensional Tectonics
Authors: Allen Langhans April , Moucha Robert , Paciga Michael Keith
Published: March 2021

The feedback between climate driven processes; weathering, erosion, sediment transport, and deposition, and extensional tectonics is limited to a few studies (Burov and Cloething, 1997; Burov and Poliakov, 2001; Bialas and Buck, 2009; Theunissen and Huismans, 2019; Andrés-Martínez et al., 2019) despite these processes having been shown to impact the stress state and deformation along active orogens (Koons, 1989; Molnar and England, 1990; Avouac and Burov, 1996; Willett, 1999). Here we utilize a fully coupled landscape evolution and thermomechanical extensional model to investigate the potential impact on faulting and extension due to lake loading changes driven by changes in climate on processional timescales. Fault analyses focusing on heave, throw, and magnitude of dip on faults generated within each model are used to characterize individual faults response to stress changes and rift basin evolution. Preliminary results indicate that fluctuations in lake levels in response to climate change may impact the lithospheric stress state by changing both fault and basin geometries within an extensional basin.
Impact of antecedent wetness and precipitation intensity on catchment travel and response times
Authors: Knapp Julia L.A. , Berghuijs Wouter R. , von Freyberg Jana , Kirchner James W.
Published: March 2021

The time a molecule of rain takes to reach the stream is normally substantially longer than the time for discharge to respond to rainfall. This difference arises because hydraulic potentials propagate through landscapes much faster than water itself does; in other words, the celerity of wave propagation is faster than the velocity of water flow. Although these concepts are well established, most catchment studies are restricted to the calculation of the celerity or response time from hydrometric information. However, to understand the storage, release, and transport of water, as well as identify flow paths through the catchment, one needs to estimate both response and travel times, requiring both hydrometric and tracer data.

We analyzed hydrometric and tracer data from two contrasting sites, the pre-Alpine Erlenbach catchment in Switzerland and the Upper Hafren catchment at Plynlimon in Wales. For both sites, hydrometric data and sub-daily isotopic tracer time series are available, enabling the calculation of response times as well as travel time distributions and new water fractions. To gain a deeper understanding of the functioning of the two catchments, we quantified these metrics and distributions for different ranges of antecedent wetness and precipitation intensity. Generally, wetter catchment conditions and higher precipitation intensities yielded faster runoff responses and shorter travel times.  Contrasts between travel and response time distributions under varying catchment conditions also facilitated more nuanced insights into catchment functioning and the effects of catchment wetness and precipitation intensity on water storage and release.
Performance evaluation of the GPM-IMERG product for flood modeling over Moroccan mountainous basin
Authors: Saouabe Tarik , El Khalki El Mahdi , Saidi Mohamed El Mehdi , Najmi Adam , Hadri Abdessamad , Rachidi Said , Jadoud Mourad , Tramblay Yves
Published: March 2021

Recently, the Global Precipitation Measurement (GPM) satellite constellation measurements combined in the Integrated Multi-satellite Retrievals for GPM (IMERG) algorithm is provided. This GPM-IMERG dataset provides potentially useful precipitation data for regions with a low density of rain gauges. This study is aimed to evaluate the accuracy of the near real-time product (IMERG-E) compared to observed rainfall and its suitability for hydrological modeling over the Ghdat watershed located upstream the city of Marrakech. Several statistical indices have been computed and a hydrological model has been driven with IMERG-E rainfall to estimate its suitability to simulate floods during the period from 2011 to 2018. The following results were obtained: (1) In terms of the precipitation detection capability, the IMERG-E performs better at reproducing the different precipitation statistics at the catchment scale rather than at the pixel scale (2) compared to the rain gauge data, satellite precipitation data overestimates rainfall amounts with a relative Bias of +35.61% (3) The flood events can be simulated with the hydrological model using both the observed and the IMERG-E satellite precipitation data with a Nash–Sutcliffe efficiency coefficient of 0.58 and 0.71, respectively. The results of this study indicate that the GPM-IMERG-E precipitation estimates can be used for flood modeling in semi-arid regions such as Morocco and provide a valuable alternative to ground-based precipitation measurements.
Analysis of 20 years of daily cloud-free chlorophyll and suspended particulate matter in the North Sea
Authors: Alvera-Azcárate Aida , Van der Zande Dimitry , Barth Alexander , Martin Samuel , Beckers Jean-Marie
Published: March 2021

The evolution of chlorophyll concentration (CHL) and suspended particle matter (SPM) in the North Sea over the period 1998-2017 is analysed. The domain covers 48 to 66 degrees North and -8 to 13 degrees East. Through the years between 76% and 87% of marine pixels are missing data due to cloud cover and satellite product quality control. A daily cloud-free dataset is produced with the help of DINEOF (Data Interpolating Empirical Orthogonal Functions). The gap-free dataset is used to investigate interannual variability and trends in the concentration of these variables in the North Sea, and their relation to long-term climatic signals such as the Atlantic Multidecadal Oscillation (AMO). The interannual variability of the initiation and length of the Spring bloom is studied, as well as its spatial dispersion. High latitudes (higher than 60°N) present large amounts of missing data due to the presence of clouds and low sun angles in winter, and therefore are more difficult to study using optical satellite data. The spatial and temporal variability of the CHL and SPM signals is assessed in these zones, like the occurrence and strength of the Spring bloom around the Faroe islands.
Integrated water vapour content retrievals from ship-borne GNSS receivers during EUREC4A
Authors: Bosser Pierre , Bock Olivier , Flamant Cyril , Bony Sandrine , Speich Sabrian
Published: March 2021

In the framework of the EUREC4A campaign, integrated water vapour (IWV) contents were retrieved over the open Tropical Atlantic Ocean using Global Navigation Satellite System (GNSS) data acquired from three research vessels : R/V Atalante, R/V Maria S. Merian, and R/V Meteor. This study describes the GNSS processing method and compares the GNSS IWV retrievals with IWV estimates from the ECMWF fifth ReAnalysis (ERA5), from the MODIS infra-red products, and from terrestrial GNSS stations located along the tracks of the ships. The ship-borne GNSS IWVs retrievals from R/V Atalante and R/V Meteor compare well with ERA5, with small biases (-1.62 kg/m2 for R/V Atalante and +0.65 kg/m2 for R/V Meteor) and a RMS difference about ~2.3 kg/m2. The results for the R/V Maria S. Merian are found  to be of poorer quality, with RMS difference of about 6 kg/m2 which are very likely due to the location of the GNSS antenna on this R/V prone to multipath effects. The comparisons with ground-based GNSS data confirm these results. The comparisons of all three R/V IWV retrievals with MODIS infra-red product show large RMS differences of 5-7 kg/m2, reflecting the enhanced uncertainties of this satellite product in the tropics. These ship-borne IWV retrievals are intended to be used for the description and understanding of meteorological phenomena that occurred during the campaign, east of Barbados, Guyana and northern Brazil.
Geologic carbon storage resource requirements of climate change mitigation targets in Europe
Authors: Zhang Yuting , Krevor Samuel , Jackson Chris
Published: March 2021

To limit global warming to well below 2oC, integrated assessment models have projected that gigaton-per-year-scale carbon capture and storage is needed by c. 2050. These scenarios are unconstrained by limiting growth rates or historical data due to the limited existing deployment of the technology. A new approach using logistic growth models identifies a coupling between storage resource base (pore space underground) and minimum growth rates necessary to meet global climate change mitigation targets (Zahasky & Krevor, 2020). However, viable growth trajectories consistent with carbon storage targets remain unexplored at the regional level. Here, we show the application of logistic modelling constrained by climate change targets and assessed storage resources for the European Union (EU), the United Kingdom (UK), and Norway. This allows us to identify plausible growth trajectories of CCS development and the associated discovered storage resource base requirement in these regions. We find that the EU storage resource base is sufficient to meet storage targets of 80 MtCO2/year and 92 MtCO2/year suggested in the European Commission climate change mitigation strategy to 2050, ‘A Clean Planet for All’. However, the more ambitious goals of 298 MtCO2/year and 330 MtCO2/year are likely to require additional storage resources based predominantly in the North Sea. Results for the UK indicate that all anticipated storage targets to achieve net-zero economy are achievable, requiring no more than 42 Gt of the storage resource base for the most ambitious target. Furthermore, the UK and the Norwegian North Sea may be able to serve as a regional CO2 storage hub. There are sufficient storage resources to support combined storage targets from the EU and the UK. The tools used here demonstrate a practical approach for regional stakeholders to monitor carbon storage progress towards future stated carbon abatements goals, as well as to evaluate future storage resource needs.

Zahasky, C., & Krevor, S. (2020). Global geologic carbon storage requirements of climate change mitigation scenarios. Energy & Environmental Science. https://doi.org/10.1039/D0EE00674B
Ensemble generation for the assimilation of dust aerosol observations
Authors: Escribano Jeronimo , Pérez García-Pando Carlos , Di Tomaso Enza , Jorba Oriol , Klose Martina , Macchia Francesca , Montané Gilbert
Published: March 2021

The generation of the ensemble forecast is a key step in the design of an ensemble-based data assimilation scheme as it bears a significant impact on the assimilation outcome. The ensemble of model states is used within the assimilation algorithm to derive a flow-dependent background error covariance which is used to express prior information uncertainty. The covariance matrix of the background errors is associated to both, the quality of the prior, and the relations between the elements of the control vector. This matrix drives the spread of the observational information through the control variables determining, in part, the quality of the analyses. Only a handful of studies have focused on investigating the generation of ensembles for aerosol data assimilation which might be compromising the optimal integration of model simulations and observations when it comes to the use of ensemble-based assimilation schemes. 

This work presents a series of design methodologies and approaches to create regional dust aerosol ensembles. We include in our experiments ensembles with and without perturbed meteorological boundary and initial conditions, spatially random source strength perturbations, perturbations of the size distribution at emission, and random perturbation of a linear combination of dust emission schemes. We compute analyses of dust optical depth by assimilating satellite dust optical depth retrievals and present our results qualitatively through the inspection of the prior correlation matrices structure, and quantitatively with a comparison against independent measurements of aerosol optical depth.

This work is in the framework of the next upgrade of the operational forecast for the WMO Barcelona Dust Forecast Center (http://dust.aemet.es/) as well as of a contributing model to the WMO Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS, http://sds-was.aemet.es/ ), both services hosted by the Spanish Meteorological Agency (AEMET) and the Barcelona Supercomputing Center (BSC).