bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential of GPS-based smartphone application data for country-wide emission estimation
Authors: Szymankiewicz Karol , Gawuc Lech , Soliwoda Marek
Published: March 2020

Road transport emissions are among the primary causes of poor air quality in cities. Typically, activity data about road transport is based on point-wise automatic traffic measurements or traffic modelling environments like VISSUM. However, such methods do not provide complete spatial patterns of emissions that are needed for air quality modelling. On the other hand, modern smartphone applications, which are used by drivers to navigate and inform about road hazards, might provide a full spatial pattern of road traffic.

We will present preliminary results of road transport emission estimates based on the application of GPS-based smartphone data. The datasets describe average speed and number of users for every road part in Poland, including both major and minor roads. The data is based on the Open Street Maps road geometry and includes more than 4.5 million road segments describing 840 thousand km of roads.
Environmental criteria for site selection of wind power projects in South Korea
Authors: Park Jong-Yoon , Lee Young-Joon
Published: March 2020

Wind energy represents the leading source of renewable energy in many developed countries. South Korea has recently introduced large-scale programs to promote the transition from fossil fuels and nuclear power to renewable energy as a source of power. The Korean government has set an energy policy goal to increase the ratio of renewable energy to 20% by 2030. To this end, it is necessary to supply renewable energy facilities with a total capacity of 48.7GW including 30.8GW of photovoltaic power generation and 16.5GW of wind power generation by the target year. Accordingly, we should plan now for the regulation of the location to meet this developing need. However, in South Korea, forests cover 63% of the country's land area so that there is a limit to find a location for the installation of large-scale power generation facilities without occupying forest lands. For example, it is mainly located in forests or farmlands where land costs are relatively low, resulting in a decrease in forest resources and negative impacts on ecosystems and landscapes. Renewable energyexpansion planning should ensure that environmental criteria, of the type outlined in this study, are given appropriate considerations in onshore wind power project site selection. Many of the more problematic wind power sites are best left mountainous forest under the natural conditions, because the environmental or related social impacts are likely to be unacceptably high. Obviously, no plans are likely to be more environmentally desirable in those cases. The alternatives for onshore wind power siting considered the environmental criteria to achieve the goal of wind energy will be suggested.
Analysis of solar radio imaging-spectroscopic observations
Authors: Yan Yihua , Zhang Minghui , Zhou Zhichao , Chen Xingyao , Tan Chengming , Tan Baolin , Wang Wei , Chen Linjie , Liu Fei , Geng Lihong , Chen Zhijun , Zhang Yin , Team Muser
Published: March 2020

Solar radio fine structures observed in wide frequency ranges are manifestations of the physical processes related to the energy release, particle accelerations and propagations, etc. The locations of these fine structures are mostly not clear so it is important to have imaging spectroscopic observations to address these problems.

Mingantu Spectral Radioheliograph (MUSER) is an aperture-synthesis imaging telescope, dedicated to observe the Sun, operating on multiple frequencies in dm to cm range. The ability of MUSER allows one to diagnose coronal magnetic field and the plasma parameters such as electron beam velocity, density, spectral index, etc.

During 2014 to 2019, MUSER has registered a number of solar radio bursts corresponding to 2 X-class, 15 M-class, 38 C-class, 19 B-class, 4 A-class and 5 below A-class flares as well as quiet Sun observations. Here we demonstrate some interesting events from MUSER imaging-spectroscopic observations.
Stability of fragmented and blocky solids
Authors: Shufrin Igor , Pasternak Elena , Dyskin Arcady
Published: March 2020

Fragmented geomaterials are discontinuous solids assembled of blocks, which are not joined together by any binder. The integrity of these solids is provided by interlocking of the interfaces between the fragments and compression applied at the boundary of the assembly. The main distinctive feature of these solids is the ability of separate fragments to move and rotate independently within the geometric constraints imposed by the neighbouring elements. Under application of external loads the fragments partially lose contact – the blocks get detached in a part of their contact area – that reduces the stiffness of entire blocky structure. The compression applied at the boundaries of the structure restores these contacts and brings shifted blocks back to their place. At the same time, this external compression can cause instability of the assembly, in particular when applied over heavily detached interfaces. This instability mechanism is highly non-linear due to the rotation of the fragments that produce elbowing effect and increases the compression.       

In order to assess the stability of fragmented solids, we carried out a series of experiments on the fragmented beams assembled of prismatic blocks and topologically interlocked osteomorphic blocks. The beams were axially prestressed and loaded in the transverse direction.  We observed that the blocky beams can exhibit negative stiffness in the certain testing regimes.  The block rotations observed during bending decrease the bending stiffness of the beam through the partial detachments between the fragments, while increasing the axial force due to the elbowing effect, which allows the beam to sustain additional bending deformations without increase in the external loading. This apparent negative stiffness is controlled by the combination of the prestress levels and rigidity of the axial beam constraints. We also verified these results through finite element simulations and analytical modelling.

Acknowledgements: This research was supported by the ISRAEL SCIENCE FOUNDATION (grant No. 1345/19).
Impact of climate change on steppe environments around Lake Sevan in Armenia during the Holocene
Authors: Robles Mary , Peyron Odile , Ménot Guillemette , Brugiapaglia Elisabetta , Ollivier Vincent , Tozalakyan Petros , Meliksetian Khachatur , Sahakyan Lilit , Joannin Sébastien
Published: March 2020

Armenia is located in the Caucasus Mountains and today, its vegetation is largely dominated by steppes closely linked with human practices. Armenian human history roots back to the Neolithic period, which questions long human influences on steppe and therefore climate reconstructions from vegetation data. Moreover, vegetation records from this region are often low resolution and do not cover the entire Holocene. Pollen-based climate reconstruction coupled to independent climate reconstructions appear necessary to fully understand climate forcing in the region during the Holocene. In this study, we introduce high-resolution pollen, geochemical analyses and temperature reconstruction based on pollen and branched glycerol dialkyl glycerol tetraethers (brGDGTs) from Vanevan peat in Armenia. The wetland studied show major ecological changes observed through aquatic vegetation and sediment composition (XRF data). At the beginning of the Holocene, the study site is expected to be integrated in a larger Lake Sevan, then it became an independent lake and finally a peatland at 5700 cal BP. A drying phase is also attested around 4.2 kyrs, probably corresponding to the 4.2 ka climate event. Along the sequence, the vegetation is characterized by steppes dominated by Poaceae, Artemisia and Chenopodiaceae. However, forests composed of Quercus, Betula, Carpinus betulus and Ulmus, are more developed on slopes between 7600 cal BP and 5500 cal BP. Agriculture is observed since 5700 cal BP and correlates with occupation periods reported in archeological studies. Over this 10000 yrs-long record, we suppose that differences in response of wetland and vegetation to climate might be linked to ecological processes and human influence. The comparison between pollen-based climate reconstruction and temperature obtained with brGDGT calibrations promisingly illustrate these differences. Finally, we contextualize these results with other regional records to understand the impact of climate change on steppe vegetation in the Caucasus at a larger scale.
Impact of tile-drainage on the hydro-sedimentary responses of hydromorphic agricultural soils by tracing water and suspended solids from the field to the catchment scale.
Authors: Gaillot Arthur , Delbart Célestine , Vanhooydonck Pierre , Cerdan Olivier , Salvador-Blanes Sébastien
Published: March 2020

Since the 1960’s, large landscape modifications were carried out to improve agriculture productivity. One of these changes was the ploughing of humid plains together with the installation of subsurface drainage, which currently represents 10 % of arable lands in the world. Studies have shown the impact of subsurface drainage on the water regime, and especially decreases in flow peaks. Drainage increases water and sediment connectivity. Less effort was devoted to investigate the impact on the erosion dynamics and very few studies were designed at the catchment scale. However, the understanding of water and suspended solids dynamics from field to catchment outlet is a key to set efficient conservation measures to reduce erosion up. Here we focus on water and suspended solids dynamics from the soil profile scale to the field scale. We propose to trace both water and suspended solids to determine the relative contributions between surface and subsurface sources. Water tracing gives indication on  pathways while suspended solids trace sources (i.e. soil surface vs. deeper soil). The study site is composed of a 5ha field within a 2500 ha agricultural catchment representative of the French agricultural intensive openfield catchments. The studied field is representative of the catchment. It is a cereal crops openfield. Two drainage methods exist in the field: subsurface drainage with drains 120 cm-deep and surface drainage with artificial channels created after the winter seeding. The soil in this field is a loamy clay soil with clay floor at 45 cm of depth. Quantification of suspended solids and water fluxes (surface and subsurface) are monitored at high temporal resolution both at the field (since January 2019) and catchment (since September 2013) scale. Since November 2019, we trace water flows (rain, soil water subsurface flow and overland flow) using water ions and stable isotopes. Suspended solids are analysed through their mineralogy and primary particle size. At the field scale, the first results show a rapid response of surface drainage to rain inputs - confirmed by ions tracing - and suspended solids are mainly coming from surface drainage. Subsurface drainage reacts with a significant delay. Ions tracing shows that subsurface runoff seems to result from a replacement of older soil water by rain inputs.
Early spring SST distribution in the Baltic Sea: in search of the coldest water
Authors: Bukanova Tatiana , Chubarenko Irina
Published: March 2020

We examine three hypotheses of formation of waters of the Cold Intermediate Layer (CIL) in the Baltic Sea: the coldest baltic waters are formed (1) at the beginning of spring warming in the Arkona and Bornholm basins, (2) in the centers of mesoscale vortexes (similar to those in the Black Sea), and (3) in the convergence zones of alongshore fronts while cooling over shelves (as in the Mediterranean Sea).

In search of the coldest surface water we analyzed the dynamics of sea surface temperature (SST) in the Baltic Proper for February-April 2003-2019 from satellite imagery of infrared sensors (MODIS-Terra/Aqua and VIIRS-Suomi-NPP), and microwave sensors (AMSR-E-Aqua, AMSR-2-GCOM-W1, and WindSat-Coriolis).

Long-term mean SST maps (for February, March, April 2003-2019) show patterns that indicate rather quick, abrupt re-structuring of thermohaline fields in late March - early April, especially evident in the Arkona and Bornholm basins. This supports the idea that seasonal transfer from two-layered winter-time vertical water stratification to the summer-time three-layered stratification is driven in the Baltic Sea not by the direct heat fluxes through the surface, but rather by the large-scale north-south water exchange.

Coastal fronts may persist for a few weeks, however their location is changeable. Stable frontal zones and vortexes are not observed under long-term SST averaging. However the sequential warming of waters from south to north direction due to geographical reasons is clearly seen with long-term averaging.

The features of spring differential warming development above shallows and along shore can be observed only from daily SST maps (not from annually averaged maps).

Investigations are supported by the Russian Foundation for Basic Research, grant No. 19-05-00717 (in part of data analysis) and the State Assignment No 0149-2019-0013 (in part of satellite data collecting and processing).
A LiDAR-based glacial landform map of the Kebnekaise massif, northern Sweden
Authors: Edward Calum , Blomdin Robin , Rosqvist Gunhild
Published: March 2020

In the face of global climate change, and the associated melting of the modern-day ice sheets, the understanding and reconstruction of the dynamics and retreats of former ice sheets has become an increasingly valuable tool and indicator of the future behaviour of present-day ice masses. The deglacial period that followed the Last Glacial Maximum (~22-9 thousand years ago) represents the most recent major warming event, and final ice sheet decay, in Earth history, and is an important analogue for the threat of present-day ice sheet collapse. The recent availability of the 2m-resolution Swedish LiDAR based terrain model provides the opportunity to map glacial landforms and landscapes over large areas with greater accuracy than was previously possible through satellite images or aerial photographs. In combination with field observation-based ground-truthing, this LiDAR resource is employed to map the geomorphology of the Kebnekaise region of the northern Swedish mountains with the principal aim of producing a landform-driven reconstruction of the deglaciation of the remnant Scandinavian Ice Sheet during its final stage of retreat. The complex ‘palimpsest’ landscape is delineated and interpreted through the classification of landforms according to their relative age and respective origin. In particular, attention will be given to the segregation of glacial (e.g., terminal moraines, lineations), deglacial (e.g., eskers, lateral meltwater channels, glacial lake shorelines) and ‘relict’ (i.e., pre-glacial palaeosurfaces) landform assemblages, in order to demarcate those formed during the final deglaciation.   The resulting landform selections are used to delineate high-resolution ice retreat patterns, giving indication to the nature of the basal thermal regime, topographic response and final remnant location of the ice sheet. Additionally, this assay serves as an evaluation of the use of the Swedish LiDAR database as a means of efficiently and accurately mapping previously-glaciated landscapes. Our deglaciation reconstruction will finally be tested against formerly produced regional reconstructions.
Comparing the long-term fate of a snow cave and a rigid container buried at Dome C, Antarctica
Authors: Brondex Julien , Gagliardini Olivier
Published: March 2020

Ice Memory is an international project aiming at creating a global ice archive sanctuary in Antarctica. The design of a perennial subsurface storage space for the cores is a cornerstone of this project. Here, we use an ice/firn flow model to investigate possible storage solutions that would meet the specific requirements of the project. To this end, we consider two extreme cases in terms of rigidity of the facility: an ice cave dug into the firn and a perfectly rigid container buried within it. We focus on the rate of sinking of the facility as well as on the rate of closure of the cave and the evolution of the normal stresses supported by the container. Our results show that the lifetime of a cave is highly affected by the initial density of snow in its surrounding. On the other hand, the presence of the rigid container within the domain perturbs the flow of snow, creating patches of high density in its surrounding and leading to significant normal stresses on its walls. In particular, strong stress concentrations are obtained at the container angles. These results prove that unreinforced shipping containers are unsuited for this task.  
Lake level changes and their paleo-climatic implications at the middle Pleistocene excavation of MAR-1, southern Greece
Authors: Bludau Ines , Weiss Max , Schnabel Ellen , Thompson Nicholas , Tourloukis Vangelis , Karkanas Panagiotis , Panagopoulou Eleni , Harvati Katarina , Junginger Annett
Published: March 2020

In the fossil-rich sediments of the Megalopolis Basin, southern Greece, the remains of an ancient paleo-lake alternate between detrital units and lignite seams deposited during the Middle Pleistocene. The detrital sediments of MAR-1 (480-420 kyr) between two lignite seams are where lithics and elephant bones with cut-marks have been systematically excavated indicating hominin activity along a paleo-shoreline circa 440 kyr. Based on current knowledge, lignite seams formed during interglacials, while the silty-clay-rich deposits in between were deposited under glacial conditions. However, the paleoenvironmental and paleoclimatic conditions on shorter times-scales, leading to the preservation of hominin activity in the area, remain largely unknown. In order to reconstruct the paleo-environment including paleo-lake levels and thus sedimentation patterns and their governing paleo-climatic factors, we analyzed a high resolution 5-meter long sediment sequence from the archaeological site MAR-1. For the reconstruction, a multiproxy approach was applied using microfossils, grain-size, and geochemical analysis such as total organic carbon, total inorganic carbon, X-ray diffraction, and conventional X-ray fluorescence. Diatoms were often too corroded to be of use, most likely due to a combination of alkaline water conditions and the influence of silicate sponges. The results of the analyses revealed that MAR-1, located between lignite unit II and III, experienced multiple lake level oscillations mostly following insolation changes suggesting that several short-term wet-dry-wet cycles occurred during the investigated period, which must have impacted flora and fauna, including hominins, in the area. This research was conducted under the auspices of the Ephoreia of Paleoanthropology and Speleology, Greek Ministry of Culture, and was supported by the European Research Council (PaGE, CROSSROADS).
Monitoring bio- geodiversity and ecosystem health by traits, remote sensing and data science approaches
Authors: Lausch Angela , Dietrich Peter , Bumberger Jan
Published: March 2020

Ecosystems fulfil a whole host of ecosystem functions that are essential for life on our planet. However, an unprecedented level of anthropogenic influences is reducing the resilience and stability of our ecosystems as well as their ecosystem functions. The relationships between drivers, stress and ecosystem functions in ecosystems are complex, multi-facetted and often non-linear and yet environmental managers, decision makers and politicians need to be able to make rapid decisions that are data-driven and based on short- and long-term monitoring information, complex modeling and analysis approaches. A huge number of long-standing and standardized ecosystem health and monitoring approaches of bio-and geodiversity exist and are increasingly integrating remote-sensing based monitoring approaches. Unfortunately, these approaches in monitoring, data storage, analysis, prognosis and assessment still do not satisfy the future requirements of information and digital knowledge processing of the 21st century. This presentation presents new concepts of monitoring of bio-and geodiversity and discusses the requirements for using Data Science as a bridge between complex and multidimensional Big Data in environmental health.

It became apparent that no existing monitoring approach, technique, model or platform is sufficient on its own to monitor, model, forecast or assess forest health and its resilience. In order to advance the development of a multi-source ecosystem health monitoring network, we argue that in order to gain a better understanding of ecosystem health in our complex world it would be conducive to implement the concepts of Data Science with the components: (i) digitalization, (ii) standardization with metadata management after the FAIR (Findability, Accessibility, Interoperability, and Reusability) principles, (iii) Semantic Web, (iv) proof, trust and uncertainties, (v) tools for Data Science analysis and (vi) easy tools for scientists, data managers and stakeholders for decision-making support (Lausch et al., 2019, 2018, 2016).

 

Lausch, A., et al., 2019. Linking Remote Sensing and Geodiversity and Their Traits Relevant to Biodiversity—Part I: Soil Characteristics. Remote Sens. 11, 2356. https://doi.org/10.3390/rs11202356

Lausch, A., 2016. Linking Earth Observation and taxonomic, structural and functional biodiversity: Local to ecosystem perspectives. Ecol. Indic. 70, 317–339. https://doi.org/10.1016/j.ecolind.2016.06.022

Lausch, A., 2018. Understanding Forest Health with Remote Sensing, Part III: Requirements for a Scalable Multi-Source Forest Health Monitoring Network Based on Data Science Approaches. Remote Sens. 10, 1120. https://doi.org/10.3390/rs10071120
Multi-labelled taxonomic prediction using a small benthic foraminifera dataset trained on a FastAi library
Authors: Amao Abduljamiu O. , Kaminski Michael
Published: March 2020

The study explored an end-to-end application of a ResNet convolutional neural network (transfer learning) to classify benthic foraminifera images using the FastAI library. 201 SEM images of 13 benthic foraminifera including Ammonia convexa, Ammonia tepida, Asterorotalia gaimardi,  Asterorotalia indica, Bulimina biserialis, Bulimina marginatta, Elphidium advenum, Elphidium hispidium, Elphidium jenseni, Elphidium neosimplex , Perenoplis arianus , Perenoplis pertusus and Quinqueloculina sp. The images were separated into two groups in a 80 -20 split for training and validation dataset respectively. We successfully trained a state-of-the-art image classifier for a very small dataset, achieving 96.5% accuracy in just a handful of lines of code on a very small dataset i.e. accurately predicting the binomial nomenclature of species. The fastai AI/Machine learning library we used offers interesting prospects in taxonomy where it can be used for multilabel image classification. Fastai’s recent research breakthroughs are embedded in the library, resulting in significantly improved accuracy and speed over other deep learning libraries, whilst requiring dramatically less code. The library sits on top of PyTorch and provides a single consistent API to the most important deep learning applications and data types. It also offers an opportunity to a novice user, new to data science to apply state of the art deep learning to practical problems quickly and reliably. It has several advantages over other known libraries is its flexibility to import data of various kind and from various sources. It is fast, has a large and friendly community backing and its immune to several limitation of other libraries.
Hydrothermal seawater-basalt exchange reactions traced by triple oxygen and strontium isotope values of fluids and epidotes
Authors: Zakharov David , Tanaka Ryoji , Lundstrom Craig , Butterfield David , Reed Mark , Bindeman Ilya
Published: March 2020

Hydrothermal circulation of seawater at mid-ocean ridges cools the oceanic crust and modulates the oceanic chemistry over multimillion-year time scales. Recent research on mass-dependent fractionation of triple oxygen isotopes allows us to gain a new insight into the seawater-basalt exchange reactions that occur within the oceanic crust. To understand the systematics of triple oxygen isotope exchange, we present a novel combined dataset for Δ17O and 87Sr/86Sr isotope values measured in modern seawater-derived vent fluids at the Axial Seamount volcano located on the Juan de Fuca Ridge and oceanic epidotes extracted from altered mid-ocean ridge basalts. Upon reaction with fresh oceanic crust, seawater evolves towards the low Mg compositions characteristic of fluids in equilibrium with basalt. In concert with decreasing Mg content and with decreasing 87Sr/86Sr, the vent fluids at Axial Seamount shift towards values that are 0.04 ‰ lower in Δ17O and 2 ‰ higher in δ18O compared to initial seawater. The 87Sr/86Sr and Δ17O values of epidotes extracted from modern hydrothermally altered basalts reveal a trend of isotope exchange similar to the one defined by the fluids. We suggest that epidotes record isotope shifts that were experienced by fluids in the areas of focused flow within the oceanic crust. Both fluids and epidotes display similar trajectories of Δ17O and 87Sr/86Sr shifts which are modeled using a Monte-Carlo simulation of reactive transport in dual-porosity medium. These trajectories provide important constraints on the physical complexity of reactive circulation of seawater within the oceanic crust. We show how the contribution of hydrothermal circulation to the isotope budget of seawater can be changed during geologic history and evaluated based on the studies of fragments of ancient oceanic crust.
Combating eutrophication in agricultural catchments: factors controlling effectiveness and challenges of changing climate and nutrient legacies
Authors: Bieroza Magdalena , Ulen Barbro , Geranmayeh Pia , Djodjic Faruk , Heeb Anuschka
Published: March 2020

Reducing eutrophication requires large financial investments that can be for example used to support catchment stakeholders in building agri-environment mitigation measures. These measures aim at reducing nutrient and sediment losses from agricultural land to recipient waters. In recent years, a large number of studies has looked into their effectiveness and generally show that some measures are successful and others fail to deliver expected improvements in water quality, which is increasingly difficult to communicate to stakeholders expecting immediate results. Particularly, transport mitigation measures that aim at intercepting stream or drainage flow, can have a varying effectiveness. Two measures of the same type and built in a seemingly similar way can have completely opposite impact on water quality, depending on the local catchment properties. In this paper we examine factors controlling effectiveness of mitigation measures looking at their hydrochemical positioning in the catchment in relation to pollution sources including nutrient legacy sources, their hydrochemical behaviour, design, management and stakeholders’ engagement, using examples for transport mitigation measures: constructed wetlands, sedimentation ponds, two-stage ditches and drainage filters. We discuss also typical trade-offs in attainment of different ecosystem services which catchment stakeholders should consider prior to selecting and building the measures, including pollution swapping mechanisms e.g. reducing P-controlled eutrophication but increasing N-controlled eutrophication or reducing eutrophication vs. increasing greenhouse gas emissions. We show also how increasing weather variability and nutrient saturation can lead to further deterioration in water quality despite implementation of measures, making mitigation efforts ineffective under changing climate and in catchments with nutrient legacy sources.

 
A regional assessment of land-based carbon mitigation options: Bioenergy, reforestation, forest management
Authors: Reiss Mona , Krause Andy , Rammig Anja
Published: March 2020

Current scenarios assume that in addition to a rapid reduction in greenhouse gas emissions, land-based carbon mitigation will also be necessary to achieve the targets of the Paris Climate Agreement. Possible measures are increased carbon sequestration via planting new forests, the cultivation of bioenergy crops, possibly in combination with carbon capture and storage (BECCS), or increasing the carbon storage of existing forests. However, currently available scenarios that are in line with IPCC storylines (SSPs, Shared Socioeconomic Pathways and RCPs, Representative Concentration Pathways) usually have  a global  perspective, while in practice mitigation projects have to be realized regionally or locally. Here, we investigate the carbon mitigation potential via alternative management of Bavarian ecosystems using an ecosystem model with an explicit representation of climate impacts and land management. Bioenergy cultivation on existing agricultural land has a larger mitigation potential than reforestation only if combined with carbon capture and storage (BECCS).  The mitigation potential in the forestry sector via alternative management is limited (converting coniferous into mixed forests, nitrogen fertilization) or even negative (suspending wood harvest) due to decreased carbon storage in product pools and associated substitution effects. Overall, the potential for land-based mitigation in Bavaria is limited because the majority of current agricultural lands will still be needed for food production and the forestry sector offers only small per-area carbon mitigation potentials.
Simulation of current and future tropospheric chemistry with the Earth System Model EMAC
Authors: Kirner Oliver , Patrick Jöckel , Johansson Sören , Wetzel Gerald , Winterstein Franziska
Published: March 2020

The increasing future methane (CH4) leads to changes in the lifetime of CH4 and in the Hydroxyl radical (OH) and (O3) mixing ratios and distribution in the lower atmosphere. With increasing CH4 the lifetime of CH4 and the O3 mixing ratios in the troposphere will increase, the tropospheric OH mixing ratios will decrease (Winterstein et al., 2019; Zhao et al., 2019). The CH4 changes, together with the future Nitrous oxide (N2O) and temperature increase, will lead to a different tropospheric chemistry. For example, substances as acetone (CH3COCH3), ethane (C2H6), formic acid (HCOOH) or peroxy acetyl nitrate (PAN) will change their distribution and mixing ratios.

In different studies we could show that EMAC (ECHAM/MESSy Atmospheric Chemistry, Jöckel et al., 2010) has the ability to simulate some of the mentioned tropospheric substances in comparison to results of the GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) instrument, used on board of the research aircrafts Geophysica and HALO during the STRATOCLIM (July/August 2017) and WISE (August to October 2017) campaigns (Johansson et al., 2020; Wetzel et al., 2020).   

In this study, we will additional show the first results of the simulated future changes of tropospheric chemistry (especially with focus on CH3COCH3, C2H6, HCOOH and PAN and the upper troposphere) related to the future increase of CH4, N2O and temperature change as a result of climate change. For these we use different EMAC simulations from the project ESCiMo (Earth System Chemistry Integrated Modelling, Jöckel et al., 2016).

We will present some results of the comparison of EMAC to GLORIA and results with regard to the future development of the (upper) tropospheric chemistry in EMAC.    
How agroforestry systems influence the abundance of nitrogen-cycle contributing microbial genes under Mediterranean conditions?
Authors: Ozbolat Onurcan
Published: March 2020

How agroforestry systems influence the abundance of nitrogen-cycle contributing microbial genes under Mediterranean conditions?

 

Onurcan Özbolat *,1, Irene Ollio1, Eva Lloret1, Marcos Egea2, Raul Zornoza1

 

1 Sustainable Use, Management and Reclamation of Soil and Water Research Group, Universidad Politécnica de Cartagena, Paseo Alfonso XIII, 48, 30203 Cartagena, Spain.

 

2 Institute of Plant Biotechnology (IBV), Campus Muralla del Mar, Edificio I+D+I, Universidad Politécnica de Cartagena, 30202, Cartagena, Spain.

 

*

 

ABSTRACT

 

Agroforestry systems represent cropping systems in which woody crops are intercropped with alley crops to increase land productivity and enhance the delivery of ecosystem services. Avoiding bare soils in the alleys and cultivation of different annual or perennial species, with shifts in tillage and/or irrigation patterns, will have an influence in organic matter turnover and nutrient cycling, mostly carbon and nitrogen, mediated by soil microbial communities. The ability of the soil to conduct a healthy relation with the microbiome and the crops is one of the most important soil quality indicators. In this study, soil samples from two different case studies where different diversification systems were applied are examined in perspective of ammonia oxidizing (amoA) and denitrifying (nirK and narG) gene abundances through quantitative-PCR assays to assess how nitrogen cycle can be modified by agroforestry systems compared to tree monocultures. The first case study included an almond orchard intercropped weather with Capparis spinosa or Thymus hyemalis. The second case study represented a mandarin orchard intercropped with a rotation of fava bean and vetch/barley or a rotation of several vegetables and vetch/barley. Abundances of amoA, nirK and narG genes significantly decreased in all intercropped systems with respect to monocultures. Thus, the special root-microorganisms and plant-plant interactions in the diversified systems contributed to soil N-cycle by decreasing the functional gene abundances. Decreasing nitrification and denitrification through management is desirable to decrease N losses and increase N fertilizer use efficiency. Thus, agroforestry systems seem more efficient in N turnover than tree monocultures where alleys remain bare most of the year.
Using Blender for Earth Science’s visualization
Authors: paronuzzi ticco stella , tinto primis oriol , Arsouze Thomas
Published: March 2020

Blender is an open-source 3D creation suite with a wide range of applications and users. Even though it is not a tool specifically designed for scientific visualization, it proved to be a very valuable tool to produce stunning visual results. We will show how in our workflow we go from model’s output written in netCDF to a finished visual product just relying on open-source software. The kind of visualization formats that can be produced ranges from static images to 2D/3D/360/Virtual Reality videos, enabling a wide span of potential outcomes. This kind of products are highly suitable for dissemination and scientific outreach.
Ecosystem-scale measurements of CO2 and CH4 fluxes from a tropical peatland in Sarawak, Malaysia
Authors: Kiew Frankie , Wong Guan Xhuan , Hirata Ryuichi , Tang Angela , Melling Lulie
Published: March 2020

Tropical peatlands of Southeast Asia are a globally important carbon reservoir, storing an enormous amount of soil organic carbon as peat. These ecosystems are complex and poorly understood with large unknown biogeochemical processes. Despite the huge carbon stocks in these ecosystems, data on ecosystem-scale carbon dioxide (CO2) and methane (CH4) fluxes are still limited in comparison with mid- and high-latitude peatland ecosystems. The recent increase in the intensity of climate anomaly such as El Niño may alter the hydrological regime of this ecosystem, thus affects its carbon cycling. It is crucial to quantify the CO2 and CH4 fluxes of the ecosystem and understand their responses to environmental changes to predict the role of peat swamp forest in global carbon cycles. To date, the application of the eddy covariance technique to measure the ecosystem-scale CO2 and CH4 fluxes in tropical peatlands is still limited to few studies in Malaysia and Indonesia.

In 2010, we established a long-term greenhouse gas fluxes monitoring using the eddy covariance technique over a peat swamp forest in Sarawak, Malaysia. Here, we present the net ecosystem exchange of CO2 (NEE) and CH4 (FCH4) from February 2014 to January 2017 (3 years). We had quantified the NEE and FCH4, the diurnal and seasonal variations of NEE and FCH4, and the response of NEE and FCH4 to GWL. The FCH4 was determined half-hourly as the sum of eddy CH4 flux and CH4 storage change in an air column below the flux measurement height. We had determined the global warming potential of this ecosystem from annual NEE and FCH4 using sustained-flux global warming potential (SGWP).  The annual FCH4 was converted into a CO2 equivalent unit using an SGWP factor of 45 which represents the SGWP for CH4 over a timescale of 100 years. Our preliminary result showed that the CH4 emission potentially offset the CO2 sequestration, which was higher than those reported in other regions in the world.
The vertical moisture structure and precipitation intensity distributions associated with tropical convective systems
Authors: Schiro Kathleen , Sullivan Sylvia , Yin Jiabo , Gentine Pierre
Published: March 2020

In the tropics, the majority of high-intensity precipitation comes from the organization of multiple convective cells into mesoscale convective systems (MCS). Here, we use a synthesis of multi-decade satellite and reanalysis data to investigate relationships between the column water vapor content (CWVC), instability (CAPE), and precipitation from MCS. We find a linear relationship between MCS maximum precipitation intensity and CAPE and a sharp, nonlinear relationship between this maximum precipitation intensity and CWVC. The latter suggests that a deep layer of inflow to the MCS dominates buoyancy and precipitation production. From these multidecade data, we can also illustrate robust shifts in the probability distributions of precipitation intensity with the El Niño Southern Oscillation. El Niño-La Niña relative gains and losses in precipitation intensity can be understood with a vertical momentum budget and the role of environmental relative humidity and large-scale circulation therein. Understanding the associated vertical moisture structure and instability is essential to better predict future variability in tropical precipitation.
Comparing different approaches for modeling reactive transport on aquifer-scale – which level of complexity is legitimate?
Authors: Schäfer Rodrigues Silva Aline , Höge Marvin , Guthke Anneli , Nowak Wolfgang
Published: March 2020

For reactive transport of solutes on aquifer-scale, measurements are usually costly and time-consuming and therefore observation data is scarce. Consequently, the system is often not fully understood and modelers cannot be sure which processes are relevant on the considered spatial and temporal scale. This lack of system understanding leads to so-called conceptual uncertainty, which is the uncertainty in choosing between competing hypotheses for a model formulation.

To account for conceptual uncertainty, modelers should work with several model alternatives that differ in their system representation. In the case of aerobic respiration and denitrification in a heterogeneous aquifer, several modeling concepts have been proposed. The approaches used in this study range from 2D spatially explicit to streamline-based models and vary considerably in their underlying assumptions and their computational costs. Typically, models that are more complex require more measurement data to constrain their parameters. Therefore, model complexity and the effort for acquiring field data have to be balanced.

In this study, we apply a concept called Bayesian model legitimacy analysis to assess which level of model complexity is justifiable given a certain amount of realistically available measurement data. This analysis reveals which number of measurements in a specific experimental setup is needed to justify a certain level of model complexity. Our results indicate that the complexity of the reference model (spatially explicit, dispersion and growth/decay of biomass included) is justifiable even by the smallest amount of synthetic measured data.
3D hydrogeological modeling of Deep Geological Disposal in the Nizhnekansky Rock massif
Authors: Neuvazhaev Georgii , Rastorguev Alexander , Morozov Oleg , Kapyrin Ivan , Grigorev Fedor
Published: March 2020

Russian Federation has a selected site for Deep Geological Disposal in the Nizhnekansky massif (Krasnoyarsk territory). The current work is devoted to justification of its suitability. One of the main parts of the safety case of is the prediction of radionuclides migration in the environment which requires development and application of groundwater flow and transport models. This work presents the evolution of the hydrogeological model.

The granitoid rock of Nizhnekansky massif is complicated by presence of such geological structural elements as dykes, faults and crushing zones which influence significantly permeability features. Currently all available geological data are consolidated with the use of the MICROMINE program into a structural geological model. The three-dimensional model of the distribution of the main structural elements in the area of the DGD site is more detailed. The corresponding dykes appear to have a north trend and a steep fall (about 70 ° east).

Using the geometry of structural elements one can assess their role in the structure of groundwater flow on the basis of profile model. Verification of the model was carried out on the basis of measured hydraulic heads.

The preliminary calculations showed that including into the model additional structural elements (to a greater extent dykes and crushing zones) leads to a better matching between observed and model heads. This implies the need to take into account the structural elements  more accurately. The migration of a conservative tracer was calculated as well using the developed flow model.

Moreover, the heterogeneity near the Deep Geological Disposal is three-dimensional in nature and it is impossible to implement it accurately in a two-dimensional setting without approximations. This requires three-dimensional modeling, such 3D numerical flow and transport models are developed using the GeRa code.
Free energy sources in kinetic scale current sheets formed in collisionless plasma turbulence
Authors: Jain Neeraj , Buechner Joerg
Published: March 2020

Spacecraft observations show the radial dependence of the solar wind temperature to be slower than what is expected from the adiabatic cooling of the solar wind expanding radially outwards from the sun. The most viable process considered to explain the observed slower-than-adiabatic cooling is the heating of the solar wind plasma by dissipation of the turbulent fluctuations. In solar wind which is  a collisionless plasma in turbulent state, macroscopic energy is cascaded down to kinetic scales where kinetic plasma processes can finally dissipate the energy into heat. The kinetic scale plasma processes responsible  for the dissipation of energy are, however, not well understood. A number of observational and simulation studies have shown that the heating is concentrated in and around current sheets self-consistently formed at kinetic scales. The current sheets contain free energy sources for the growth of plasma instabilities which can serve as the mechanism of the collisionless dissipation. A detailed information on the free energy sources contained in these current sheets of plasma turbulence is lacking but essential to understand the role of  plasma instabilities in collisionless dissipation.

We carry out 2-D hybrid simulations of kinetic plasma turbulence to study in detail free energy sources available in the current sheets formed in the turbulence. We focus on three free energy sources, namely, plasma density gradient, velocity gradients for both ions and electrons and ion temperature anisotropy. Our simulations show formation of current sheets in which electric current parallel to the externally applied magnetic field flows in a thickness of the order of an ion inertial length. Inside a current sheet, electron flow velocity dominates ion flow velocity in the parallel direction resulting in a larger cross-gradient of the former. The perpendicular electron velocity inside a current sheet also has variations sharper than the corresponding ion velocity. Cross gradients in plasma density are weak (under 10 % variation inside current sheets). Ion temperature is anisotropic in current sheets. Thus the current in the sheets is primarily due to electron shear flow. A theoretical model to explain the difference between electron and ion velocities in current sheets is developed. Spacecraft observations of electron shear flow in space plasma turbulence will be pointed out.   

These results suggest that the current sheets formed in kinetic plasma turbulence are close to the force free equilibrium rather than the often assumed Harris equilibrium.  This demands investigations of the linear stability properties and nonlinear evolution of force free current sheets with temperature anisotropy. Such studies can provide effective dissipation coefficients to be included in macroscopic model of the solar wind evolution.   
First results of model sensitivity studies on the influence of global changes to the North and Baltic Seas
Authors: Ehlers Birte-Marie , Janssen Frank , Abalichin Janna
Published: March 2020

The “German Strategy for Adaption to Climate Change” (DAS) has been established as the political framework to climate change adaption in Germany. One task of the “Adaption Action Plan of the DAS” is the installation of a permanent service of seamless climate prediction. The pilot project “Projection Service for Waterways and Shipping” (ProWaS) prepares an operational forecasting and projection service for climate, extreme weather and coastal and inland waterbodies. The target region is the North Sea and Baltic Sea with focus on the German coastal region and its estuaries.

ProWaS provides regional model setups for the North and Baltic Seas. To figure out technical issues and to validate the model setups, 20-year hindcast simulations forced with a regional reanalysis (COSMO-REA6 (Bollmeyer et al., 2015)) were carried out.

These simulations are used as basis for sensitivity studies with reference to global change scenarios. To evaluate the effect of global changes on the coastal regions especially in the North and Baltic Seas, model studies regarding global sea level rise, changes in global ocean and air temperature, changes in global salinity and changes of the regional river runoffs have been performed. Therefore, boundary conditions of a hindcast simulation are adapted to different change conditions and sensitivity studies for different periods have been carried out. First results of these investigations on model sensitivity studies are presented. These results will be used as a basis for further development of climate projection models.
Spatial and Temporal Variations of Eutrophication in Poyang Lake
Authors: huang aiping
Published: March 2020

Lake eutrophication is a key point in water environmental problems in the world. Spatiotemporal variations of nutrients and chlorophyll-a and eutrophication index in Poyang Lake, the largest freshwater lake in China, are analyzed in this paper basing on field observation data at 17 sampling points from 2011 to 2016. The results show that nutrient concentrations have obvious seasonality characteristics and present bigger values in the low water period than the high water period. The peak value of chlorophyll-a concentration appears in July and October respectively. As a whole, the eutrophication index in the low water period is higher than the high water period, and the maximum value is found in October which mainly due to the high chlorophyll-a concentration. Poyang Lake is at light eutrophication level from 2011 to 2012, and mesotrophic from 2013 to 2016. From the perspective of space, nutrient concentrations in the southern part of the lake is higher than the northern part in general, and chlorophyll-a and eutrophication index show the similar law. This paper makes a quantitative analysis for spatial and temporal variations of eutrophication which benefit the water management especially water pollution control in Poyang Lake