bluuebunny/crossref_metadata_2025 huggingface dataset:
Wildfire spreading across the urban area: definition and mapping of vegetation connectivity
Authors: Polinova Maria , Kutiel Haim , Wittenberg Lea , Brook Anna
Published: March 2020

Climate change, increased frequency of natural disasters and their anomaly in the modern world demand review existing knowledge about environment and approaches for its management. In recent decades, one of the phenomena that humanity met with is urban wildfires. Experience has shown that existing approaches from forest fire management are not effective in a built-up environment. In practice, studying this phenomenon is limited due to lack of empirical knowledge.

To bridge this knowledge gap, the fire dynamic patterns in an urban area was reconstructed based on fire service data on the example of wildfire in Haifa (Israel) in November 2016. The results of reconstruction show that unlike forest fires, where fuel is almost unlimited around the ignition point, urban areas are sensitive to wildfire because of 'fire connectivity' through vegetation: fire moves from one green patch to another, bypassing nonflammable structures.

Although the role of urban vegetation in the spread of fires is obvious, it is difficult to define a suitable term in case of fire management. Today, cities and vegetation are studied together in the urban planning and ecosystem services and have different definitions, depends on study propose: ‘Urban Green Spaces’, ‘Green Infrastructure’, ‘Urban Forestry’, etc. The closest term in fire management for vegetation interaction with structures is ‘Wildland Urban Interface’ (WUI). However, WUI considers vegetation surrounding the city and excludes urban green spaces. Since before this time the inner-city vegetation was not considered in the fire management and wasn’t estimated its essential parameters for this case, it does not have an exact term and definition. The reconstructed wildfire allows to analyze and define vegetation in context of fire connectivity.

The results show that wildfire spreads in the urban area through ember attacks. Meanwhile, the embers led to ignition only in some patches and only in a few cases the energy amount was enough for new embers emission. Thus, the fire vegetation connectivity in urban areas can be defined by its ability to ignite and reproduce new embers.

To support fire management and risk assessment in urban areas, it is important to map vegetation based on its ignitability and potential energy emission. The task is complicated due to the uncertainty of surface fuel (including both litter and human waste). Citywide, detecting and monitoring such patches through field surveys is time-consuming work. To solve this objective by remote sensing technique, we analyzed series of Landsat 8 images for 2015 to identify spectral and temporal features of vegetation related to its flammability. The proposed approach supports estimation and mapping of vegetation connectivity in case of urban wildfire based on its multi-temporal spectral signature.
System for supporting detailed implementation plan on measures for adaptation to climate change of local governments
Authors: Jung Huicheul , Kim Jaeuk , Yu Insang , Lee Sung-Hun
Published: March 2020

It is mandatory to establish a detailed implementation plan on measures for adaptation to climate change of local governments, based on the Article 48 of the Framework Act on Low Carbon, Green Growth and Article 38 of the Enforcement Decree of the same Act of South Korea. However, it is difficult for local governments to establish such detailed implementation plan due to high budget spending, lack of experts in climate change field and the shift in cyclical positions of government officials. The Korea Adaptation Center for Climate Change(KACCC) has developed a system for supporting local governments to overcome the difficulties. The system provides integrated data regarding climate change adaptation, such as general information, current status and prospect of climate change, climate change impact analysis, vulnerability and risk assessment to climate change using VESTAP (Vulnerability Assessment Tool to Build Climate Change Adaptation Plan) for each region. Based on the integrated information regarding adaptation to climate change, local governments conduct a survey targeting general public, civil servants, experts, etc. using the questionnaire on adaptive awareness provided by the system. Each local government can analyze the information and inventory of adaptation measures and diagnose the policies to establish detailed implementation plans for each sector. By establishing the system, it is expected to support government officials’s task through standardization and automation of detailed implementation plans and reduce budget and time required for data collection and analysis. It is possible to improve the quality and maintain the consistency of plans by local governments. The system also supports decision making by rapid and reasonable adaptation measures leading to establishing highly effective and managed implementation plans for local governments.

※ This work was supported by Korea Environment Industry & Technology Institute(KEITI) through Climate Change Correspondence Program, funded by Korea Ministry of Environment(MOE)(2018001310004).
A Versatile and Complete Technology Platform for Autonomous Ocean Bottom Seismometry
Authors: Moores Andrew , Townsend Bruce , Pigeon Sylvain , Somerville Ted
Published: March 2020

Ocean Bottom Seismometry has more constraints than terrestrial seismometry due to the challenging environment, complex logistics and high costs associated with operating on the seafloor. However, the scientific objectives of a station are the same: to reliably record high-quality ground motion signals with sufficient fidelity to discern phenomena of interest that manifest above the baseline background earth noise at any given site. To better address the specific needs and challenges of ocean bottom seismology, Nanometrics in conjunction with Scripps Institute of Oceanography, is developing a comprehensive OBS solution that comprises versatile but compact instrument platforms, ultra-low power high-performance seismometers and datalogger, and an end-to-end workflow that spans the entire process from on-shore campaign design to shipboard operation, delivering ready-to-use complete datasets. Recent SWaP (Size, Weight and Power) breakthroughs in seismometer and datalogger technology realize more than 50% power reduction and 40% size/weight reduction for broadband and very broadband sensors, and high precision low-power digitizing technology, which together offer very low noise OBS stations with extremely low power consumption. This next-generation seismometer technology is based on proven intermediate and very broadband sensors that have been deployed widely by oceanographic institutes globally. Key benefits of the complete OBS ecosystem and end-to-end workflow include significantly extended deployment durations, the same seismic sensor performance options for OBS as on land,from geophones to the newest generation of ultra broadband seismometers, optimal operational cost resulting from greatly improved ease-of-use and low SWaP, and high outcome certainty due in part to integrated simple workflows designed specifically for the autonomous OBS use case. Ultra-fast harvesting of data produces a ready-to-use dataset including automatically generated StationXML response metadata and automatic time correction, and facilitates rapid recovery and redeployment of OBS stations.  

 
An atmospheric surface layer study: The Idealized horizontal Planar Array experiment for Quantifying Surface Heterogeneity (IPAQS)
Authors: Morrison Travis , Calaf Marc , Pardyjak Eric , Hultmark Marcus , Higgins Chad , Iungo Giacomo , Drake Stephan , Hoch Sebastian , Zajic Dragan , Perelet Alexei , Bingham Alex , Brunner Claudia , DeBell Thomas , Gunawardena Nipun , Huang Yi-Chun , Mogollon Gabe , Najafi Behzad , Pandya Yajat , Puccioni Matteo , Kumar Singh Sr Dhiraj
Published: March 2020

Numerical weather prediction models rely heavily on boundary-layer theories, which poorly capture the interactions between the Earth’s heterogeneous surface and the internal boundary layers aloft. Further, in relation to these theories, there remains outstanding questions that still require new understanding, such as the closure of the surface energy balance, advection quantification, and surface-flux interaction. We hypothesize that under certain conditions of unstable and neutral stratification, surface thermal heterogeneities can significantly influence the flow structure and alter momentum and scalar transport. To be able to access this hypothesis, we designed the Idealized horizontal Planar Array experiment for Quantifying Surface heterogeneity (IPAQS). IPAQS took place during the summers of 2018 and 2019 at the Great Salt Lake Desert playa in western Utah at the U.S. Army Dugway Proving Ground’s Surface Layer Turbulence and Environmental Test (SLTEST) facility. The site is characterized by a long uninterrupted fetch with uniform surface roughness and large thermal and moisture heterogeneities covering a wide range of scales. Observations were made with an array of 2-m high, temporally-synchronized, fast-response sonic anemometers, and finewire thermocouples, which were deployed on a coarse grid covering an area of 800 m x 800 m with 200-m spacing. Results provide valuable insight into the spatial and temporal evolution of the flow. Fine-scale turbulence was measured using Nano-Scale Thermal Anemometry Probes (NSTAP). Meanwhile, larger-scale turbulence was captured with Doppler wind LiDARs. Presented is an overview of the experiment and initial results.
An Empirical Model of Electron Flux from the Seven-Year Van Allen Probe Mission
Authors: Gabrielse Christine , Roeder James , Lee Justin , Claudepierre Seth , Turner Drew L. , O'Brien T. Paul , Fennell Joseph , Blake J. Bern
Published: March 2020

The near-Earth radiation environment is a force to contend with when designing satellites and their instruments. Solar storms can accelerate and transport energetic particles closer to Earth, populating Earth’s radiation belts and increasing a satellite’s radiation dosage. A major application to the field of space weather is therefore knowing and understanding the near-Earth radiation environment. We use Van Allen Probe data throughout mission lifetime to look at electron fluxes at different energies, pitch angles, and L shells, creating a daily average flux model that can be used to deduce what fluences were observed by any satellite that flew within Van Allen Probe’s seven-year mission. We supplement Van Allen Probe fluxes with THEMIS statistical fluxes at higher L shells. This model can be applied to better understand satellite degradation issues related to the radiation environment. It is an improvement from previous empirical models in this regard by virtue of the fact that actual fluxes from a specific storm (or storms) can be deduced and compared to real satellite degradation data.
The effects of tidal changes on the frequency of nuisance flooding events in the United States
Authors: Li Sida , Wahl Thomas , Jay David , Talke Stefan , Liu Lintao
Published: March 2020

Nuisance flooding (NF) or high tide flooding describes minor nondestructive flooding which can nonetheless cause substantial negative socio-economic impacts to coastal communities. The frequency of NF events has increased and accelerated over the past decades along the U.S. coast, leading to changes ranging from 300% to 900%. This is mainly a result of sea level rise reducing the gap between high tidal datum and flood thresholds. While long-term relative sea level rise is the main driver for the increased number of NF events, other factors such as variability in the Gulf stream, the storm climate, and infragravity waves can also contribute. Another important driver that is often overlooked is related to changes in coastal and estuary tides, through secular trends in the amplitudes of major tidal constituents. In this presentation we assess the role of tidal changes in modulating the frequency of NF events along the U.S. coastline. We analyze hourly records from 49 U.S. tide gauges for which the National Weather Service has defined NF thresholds. We find that (1) overall across all tide gauges the number of NF days has increased since 1950 due to changes in coastal tides, adding up to 100 NF days in recent years (on top of the increase due to relative sea level rise), (2) more tide gauges experience an increase in NF events than a decrease due to changes in tides, (3) tide gauges in major estuaries which have undergone major anthropogenic alterations experience the strongest changes; in Wilmington (Cape Fear estuary), for example, 10-40% of NF events in recent years can be attributed to tidal changes. 
Estimation of Wind Speeds in Urban Areas Using Look-up Tables for Wind-speed Change Rate Simulated by a CFD Model
Authors: Wang Jang-Woon , Kim Jae-Jin , Yang Ho-Jin
Published: March 2020

In this study, we developed a new urban parameterization method of wind speeds. The parameterization method uses building morphology parameters (the volumetric fraction, the plane area fraction, and the average height of buildings) for three different areas. For this, we investigated the relationships between the wind speed change rates by buildings and the urban parameters in three target areas. Each target area includes an automated weather station (AWS) at its center. We conducted the multiple regression analysis to make look-up tables for the relationships between the wind speed change rates and the urban morphology parameters for 32 inflow directions in the target areas. For validation, we simulated the wind speeds at the AWSs using a CFD model coupled to the local data assimilation and prediction system (LDAPS), one of the operational numerical prediction systems of the Korean Meteorological Administration. The results showed that the estimated wind speeds at the AWSs in the three target areas were very similar to those simulated by the LDAPS-CFD coupled model as well as those observed at the AWSs.
Experimental and CDEM Analysis on Crack Propagation Mechanism of Rock-Like Material Containing Flaws Under Uniaxial and Biaxial Compression
Authors: Li Yong , Zhu Weishen , Wei Chao , Cai Weibing , Wu Guannan , Wang Zhiheng , Kong Weiqiu
Published: March 2020

Abstract: Uniaxial and biaxial tests are performed to investigate the evolution mechanism of crack propagation and coalescence through developing newly cement mortar materials with horizontal and inclined pre-existing flaws. Additionally, a new numerical method-CDEM (Continuous discrete element method) is employed to analyze the evolution laws of stress field of crack tips under hydraulic coupling. The results reveal that the maximum principal stress of the wing crack tip gradually decreases with increase of internal water pressure, and the initiation stress, initiation angle and peak strength show decreasing trend. The results of crack propagation and coalescence obtained by numerical simulation is consistent with laboratory results. With the water pressure increases, prior to the occurrence of wing cracks, the coplanar cracks firstly initiate around inclined flaws. Under the coupling action of uniaxial compression and internal water pressure, the lateral pressure would limit the initiation of the wing cracks, while the increasing water pressure weakens the inhibition of lateral pressure on wing cracks.
Exploiting the characteristics of volcanic lightning for volcano monitoring
Authors: Behnke Sonja , Edens Harald , Senay Seda , Swanson Diana , Van Eaton Alexa , Schneider David , Iguchi Masato , Miki Daisuke
Published: March 2020

Volcanic lightning measurements are gaining momentum in the volcano monitoring community as a tool to identify when an ash producing eruption has occurred. As a volcanic plume develops from an ash-laden jet to a convective plume, the electrical discharges also evolve, ranging from small “vent discharges” (a few meters in length) and near-vent lightning (tens of meters to kilometers in length) to thunderstorm-like plume lightning (tens of kilometers in length). Currently, volcanic lightning monitoring capabilities for volcano observatories are mainly limited to using long-range lightning sensor networks, which do not detect the full gamut of volcanic lightning due to the networks’ detection efficiency and the radio frequency band that they use (very low frequency or low frequency). This biases the sensors towards detecting only the larger volcanic lightning discharges that occur at later stages in plume development, which can result in detection delays of minutes to tens of minutes from the onset of eruption. In addition to the latency, there is no way to know if the lightning picked up by long range networks is from a volcanic or meteorological source without some other additional source measurement. Both the latency and the source ambiguity could be reduced by using lightning sensors at close range that can detect the very small vent discharges associated with volcanic explosions. Vent discharges occur within the gas thrust region in a plume, starting simultaneously with the onset of an eruption and persisting continually for seconds or tens of seconds, depending on the duration of an eruption. They produce a distinctive ‘continual radio frequency’ signal, of which there is no analogous signature in meteorological lightning. Thus, the characteristics of the radio frequency signature of vent discharges could be exploited to innovate a new sensor design that is both low power and transmits information (i.e., a useful derived data product) at rates low enough to be used at remote volcanoes where volcano monitoring is often sparse. To meet this goal, a new experiment at Sakurajima Volcano in Japan is underway to learn more about the physical characteristics and signal characteristics of vent discharges. We use broadband very high frequency sensors to record time series measurements of the vent discharges and other volcanic lightning discharges that occur from explosions of the Minamidake crater of Sakurajima. These measurements reveal new information about vent discharges, such as their duration and spectral features, that can be used to help identify when explosive eruptions are occurring.
Hindsight 2020: X-ray Spectroscopy on Mars, Challenges, Results and Future.
Authors: Gellert Ralf
Published: March 2020

Three generations of the Alpha-Particle-X-ray-Spectrometer (APXS) have been part of the science suite on all four landed NASA Mars rovers so far. Using x-ray spectroscopy following excitation with alpha particles and x-rays from 244Cm radioactive sources, so far about 2000 samples have been investigated along the combined traverse of ~85km on the surface of Mars.

The APXS reports 16 standard elements in all samples and additional trace elements like Ge, Cu, Ga, Rb, Sr, As, Se, Y and Pb if at elevated levels. The sample spot of ~ 20 mm diameter is often large enough to represent bulk content, though small enough to reveal evidence for certain minerals through element correlations when oversampled in rasters. The results from all missions revealed large scale sedimentary formations, like Murray and Burns indicating specific environmental conditions in the past. The soil was found similar at all sites, representing a well mixed global crust component. APXS geochemical data were used for important constraints of complimentary mineralogy results, ground truth for orbiters and comparison to Martian meteorites.

Results from the ongoing Curiosity mission and the long living MER rovers will be discussed. Additionally, some very successful applications and investigations that were serendipitously developed after launch will be reviewed. Part of the presentation will be devoted to the unique challenges, trade-offs during design and lessons learned from the long operation of the instrument. The combination of APXS, XRD and Moesbauer results from MER and MSL with future fine scale XRF results of the soil at the Mars 2020 landing site might shed a light into the enigmatic amorphous phase, which could represent a record of the past alteration processes on Mars.
Participation of the private sector in Seabed Mapping Programs
Authors: Edderouzi Assia
Published: March 2020

One of the biggest ongoing trends related to oceans is the growth of the Blue Economy, that is described as the sustainable use of ocean resources for economic growth, improved livelihoods and jobs, and ocean ecosystem health. In the EU only, it represents roughly 5.4 million jobs and generates a gross added value of almost €500 billion a year. Unlocking the value of the blue economy requires mapping our oceans with both environmental and social dimensions. To achieve this, it is of vital importance to have support and participation from governments, the scientific community and the private sector. Global initiatives like the Decade of Ocean Science for Sustainable Development and SeaBed2030 are good platforms for these stakeholders to overcome internal institutional inertia or distrust of novel types of partnerships, to consolidate or share existing data and help map areas where no data exist. The private sector in particular is key to reach the goal of a comprehensively mapped seafloor. We cannot rely solely on current academic scientific research funding mechanisms. Government funding for academic research is limited, and competition for grants can be expected to remain high in the future. Business can provide much more than just simple funding of Seabed Mapping projects. R&D, Local Content and Participation, Data Stores, Capacity Building and PR are just few examples. The private sector can help affect policy change through lobbying efforts, train the next generation of Ocean Mappers and Scientists, and help to create sustainable practices within the oceans.  So why aren’t more companies investing in these important initiatives? Here we will discuss reasons behind this lack of active participation. We will also explore ways encourage the private sector to think beyond “business as usual” and take ambitious actions in advancing ocean science toward addressing societal needs. Furthermore, we will showcase studies where this collaboration has been effective. The ball is in the “business court”. It is imperative that this sector shifts mindset, allowing data to live beyond its own immediate needs and serve the maximum good. When this happens, together we will move ocean science forward and meet our shared goal of a healthy, sustainable ocean for generations to come.
Standard variables influencing geodiversity
Authors: Zwoliński Zbigniew
Published: March 2020

The existing assessments of geodiversity are based on very different abiotic elements of the natural environment. This makes these assessments incomparable between different areas and obtained by different methods. Therefore, it is sometimes difficult to say in comparative studies which area is more or less geodiverse. The search for unambiguous geodiversity assessments is one of the most important challenges in the current era of climate change and environmental exploitation. This presentation aims to indicate those elements of the natural environment and their parameters that are independent of the specificity of the area being assessed. The specificity of the assessed area may vary in many aspects, e.g. genesis and provenance, age and evolution, hypsometry and geomorphometry, geology and lithology, soil and surface sediments, climate zones, groundwater and surface water supply, etc. Is it possible to find such variables that will be universal and objective in assessing geodiversity with such a variety of abiotic elements of the environment? During the presentation, an attempt will be made to answer the above question. The suggestion of this answer should be a contribution to the discussion on the scope of the standard variables influencing geodiversity.
Variability of PM pollution in the light of emission changes and meteorological variability: a case study for Styria, Austria
Authors: Schmidt Christian A. , Huszár Peter , Mayer Monika , Fritzer Johannes , Rieder Harald E.
Published: March 2020

Despite ambitious efforts to abate surface air pollution, the air quality thresholds for PM10 and PM2.5 are regularly exceeded in the state of Styria. PM target levels are most frequently exceeded in industrial regions and urban cores of the forelands preceeding the alps. Besides local emissions, ambient meteorology and particularly stagnation are of special importance for PM pollution. Here we assess local and regional changes in PM pollution following emission reduction measures, while simultaneously considering effects of meteorological variability. We further supplement our observational study with a set of high-resolution chemistry-transport-model (CTM) simulations to assess future changes in the PM burden in Styria.
Impact of urban expansion and warming climate on sea-breeze circulations: A numerical study in the Greater Houston Metropolitan Area
Authors: Tewari Mukul , Singh Jitendra , Ray Pallav , Georgescu Matei , Salamanca Francisco , Treinish Lloyd
Published: March 2020

The Building Effect Parameterization + Building Energy Model (BEP+BEM) with a detailed urban parameterization coupled with the Weather Research and Forecasting (WRF) model is used to simulate the summertime local circulation in the Houston, Texas metropolitan area. Six numerical model simulations at 3km horizontal resolutions (within the nested parent domain of 9km) are performed using land use data representative of 2010, and 2100.They include:

(a) Control Simulation (with 2010 land use with current and future climate)

(b) same as (a) but with less aggressive urban expansion

(c) same as (a) but with more aggressive urban expansion

For future climate simulation, CCSM4 data (RCP8.5 scenario) were used to generate the climate perturbation, which was then applied to the current forcing data (NCEP final analyses) used for the numerical model simulations. Validation is based on comparison between model simulations and observations and it shows reasonably good model performance. Numerical simulations show an important interaction between the sea breeze and the urban heat island (UHI) circulation. The UHI forms a strong convergence zone in the center of the city and accelerates the sea-breeze front toward it. This phenomenon raises several questions.  (1) With urban expansion, how is the sea breeze penetration modified?  What is its impact on energy consumption in the city during the summer season, (2) After the dissipation of the UHI, how does the penetration of sea breeze change?  (3) How is the speed of the sea breeze modified with climate change and/or urban expansion? We will discuss our approach and present our results that help answer these questions.
Effect of soil C model structural uncertainty on global projections
Authors: Vladimirov Artem , Vasilyev Taras , Vasilyeva Nadezda
Published: March 2020

In this study we apply the family of mathematical models for soil organic carbon (SOC) dynamics to estimate the effect of SOC model structural uncertainty on global scale C  projections. The model family features switchable biological and physical mechanisms (such as explicit microbes, dynamic CUE and turnover, priming effect, dynamic adsorption strength and physical occlusion) in a single modeling framework where mechanisms can be turned on and off without affecting model parameters that are not involved in a given mechanism. The model family fit to experimental chronosequence data provided uncertainty ranges for mechanism-specific parameters and individual models likelihood.

Selected models were run with litter fall, soil surface temperature and moisture from Earth System Model (ESM) simulation as an input, while model parameters were randomly distributed according to their uncertainties. Variance of obtained model trajectories in a given time frame was assumed as a lower estimate for model prediction uncertainty. Different models in the family were compared by their prediction uncertainty in addition to their likelihoods to obtain the final estimate for efficiency of a certain model for ESM.
NOOS-Drift, an innovative operational transnational multi-model ensemble system to assess ocean drift forecast accuracy.
Authors: Legrand Sebastien , Dagestad Knut-Frode , Daniel Pierre , Kapel Michel , Orsi Samuël
Published: March 2020

In case of maritime pollution, man-overboard, or objects adrift at sea, national maritime authorities of the 9 countries bordering the European North West Continental Shelf (NWS) rely on drift model simulations in order to better understand the situation at stake and plan the best response strategy. So far, the drift forecast services are mainly managed at national levels with almost no integration at the transnational level. Designed as a support service to the national drift forecasting services, NOOS-Drift has the ambition to change this paradigm.   

NOOS-Drift is a distributed transnational multi-model ensemble system to assess and improve drift forecast accuracy in the European North West Continental Shelf. Developed as a one-stop-shop web service, the service allows registered users (national drift model operators or trained maritime authorities) to submit on-demand drift simulation requests to be run by all the national drift forecasting services connected to NOOS-Drift. Within 15 minutes after activation, the NOOS-Drift users shall get access to the drift simulation results of the individual ensemble members, as well as the results of a multi-models joint analysis assessing the ensemble spread and delineating risk areas to locate possible maritime pollution. This operation of such a distributed multi-models service is to our knowledge a world premiere. 

In this communication, we will present the technical and scientific developments that had to be done to make this service possible, including: 

a robust, secure and latency-free communication system that coordinates the execution of the different national models

a strategy to build the multi-model ensemble

a definition of drift forecast accuracy

the joint multi-model analysis tools

the standard file formats and visualisation means 

Finally we will illustrate on an example how the NOOS-Drift service could change the decision making process.
Transnational Access to on-site modelling resources and hazard assessment tools: Establishing the pillars of scientific collaboration.
Authors: Geyer Adelina , Ronchin Erika , Jimenez Diana , Martí Joan , Martínez Marc
Published: March 2020

The Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC) is the largest public multidisciplinary research organization in Spain. The Institute of Earth Sciences Jaume Almera (ICTJA) of Barcelona is one of the main CSIC centres dedicated to Earth Sciences. The Group of Volcanology of Barcelona (GVB), part of Environmental Geology and Geohazards of the ICTJA,  has vast experience in numerical and experimental modelling of volcanic and related processes, as well as in the development of hazard assessment and risk management e-tools and methodologies to be applied in active volcanic regions. Within the framework of the EUROVOLC project, the GVB-ICTJA has offered physical access to on-site modelling resources including initial training, guidelines and technical assistance to simulate with the FEM modelling software COMSOL Multiphysics: (i) thermo-fluid dynamic processes occurring during the phases of magma injection, accumulation and cooling and (ii) local and regional stress field of a volcanic area. The on-site access has been complemented with further remote assistance to the users to help finishing their research work. Additionally, the ICTJA has provided on-site access to VOLCANBOX (http://www.volcanbox.eu), an e-tool that integrates, in a systematic and sequential way, a series of well-tested tools addressing various aspects of the volcanic hazard processes and risk assessment. E-tools-computer or Web-based applications can help users employ probabilistic methods to assess and forecast volcanic eruptions and hazards, as well as their spatial and temporal likelihood of occurrence. In the first Transnational Access Call opened by the EUROVOLC project two accesses were funded, one for each offered installation. Thanks to the activities carried out during both accesses, the pillars for future scientific collaboration between the visiting research groups and the GVB-ICTJA have been successfully  consolidated.

These activities were funded  by the EUROVOLC project (Horizon 2020 Grant Agreement: 731070).
Diachronous Tibetan Plateau landscape evolution derived from lava field geomorphology
Authors: Allen Mark , Law Robert
Published: March 2020

Evolution of the Tibetan Plateau is important for understanding continental tectonics because of its exceptional elevation (~5 km above sea level) and crustal thickness (~70 km). Patterns of long-term landscape evolution can constrain tectonic processes, but have been hard to quantify, in contrast to established datasets for strain, exhumation and paleo-elevation. This study analyses the relief of the bases and tops of 17 Cenozoic lava fields on the central and northern Tibetan Plateau. Analyzed fields have typical lateral dimensions of 10s of km, and so have an appropriate scale for interpreting tectonic geomorphology. Fourteen of the fields have not been deformed since eruption. One field is cut by normal faults; two others are gently folded with limb dips <6o. Relief of the bases and tops of the fields is comparable to modern, internally-drained, parts of the plateau, and distinctly lower than externally-drained regions. The lavas preserve a record of underlying low relief bedrock landscapes at the time they were erupted, which have undergone little change since. There is an overlap in each area between younger published low-temperature thermochronology ages and the oldest eruption in each area, here interpreted as the transition between the end of significant (>3 km) exhumation and plateau landscape development. This diachronous process took place between ~32.5o - ~36.5o N between ~40 and ~10 Ma, advancing northwards at a long-term rate of ~15 km/Myr. Results are consistent with incremental northwards growth of the plateau, rather than a stepwise evolution or synchronous uplift.
Assessing China's Digital Economy and Environmental Sustainability: A Regional Low-Carbon Perspective
Authors: Piao Xiuting , Cui Xuefeng
Published: March 2020

Digital economy is becoming a new engine of China's economic transformation, leading a new path of green and low-carbon development. However, the positive and negative effects of the digital economy on the environment have also been widely debated. The energy consumption of China's digital economy industry is still increasing, but it has received little attention. This paper studies the emerging links between digital economy and low-carbon sustainable development. Understanding the impact of the digital economy on carbon emissions is critical to addressing the challenges of climate change in the digital age.

By integrating input-output methods, this paper establishes a comprehensive framework to evaluate China's digital economy and environmental sustainable development. It can not only evaluate the carbon emissions in various sub-industries of the digital economy, but also reveal its formation and change mechanism by determining its source industries, transfer paths and economic drivers. Using STIRPAT model and provincial panel data from 2001 to 2016, this paper investigates the impact of the digital economy industry on carbon emissions at the national and regional levels. In addition, assess the carbon footprint of the entire digital industry, including the relative contribution of major infrastructure, core and integration components of the digital economy to carbon emissions. The results show that the digital economy helps reduce China's carbon emissions. The digital economy in the central region has a greater impact on carbon emissions than the eastern region, while the western region has unconspicuous impact. With the emergence of the digital economy in the energy system, energy consumption can be reduced and energy efficiency can be improved, which can help reduce carbon emissions in the energy sector, and contribute to the sector's carbon emission reduction goal of about 3%. The positive and negative impacts of the digital economy on the environment have resulted in an inverted U-shaped relationship between the digital economy and carbon emissions. The inflection point of the digital economy is slightly higher than the medium level, which means that carbon emissions may increase further with the development of the digital economy at this stage. Without control, the relative contribution of the digital economy to carbon emissions may exceed 10% by 2030. These findings not only help to advance the existing literature, but also deserve special attention from policy makers.
Development of a big data system to assess ecosystem services of surface soil
Authors: Lim Kyoung Jae , Lee Dongjun , Kim Jonggun , Yang Jae E , Shin Minhwan
Published: March 2020

A big data system plays a significant role in various fields. This technology has also been applied to environment fields because it can discover hidden patterns between environmental factors. As the massive data set was constructed for several decades, big data analysis has widely been using for extracting useful information by analyzing different types of big data sets. In this study, we developed a big data system frame to assess the ecosystem service provided from surface soil. Among big data platforms, we used the Amazon Web Service (AWS) due to their cost-efficiency and hardware flexibility. There are five stages of the big data system (i.e. data acquisition– data storage – data processing – data analysis – visualization). In the data acquisition step, the soil sensor and Internet of Things (IoT) system were used, and we collected existing soil properties data provided by national institutes such as Rural Development Administration (RDA), Ministry of Environment (MOE), and Ministry of Land, Infrastructure, and Transport (MOLIT). AWS S3 platform, which is an object storage service and provides easy-to-use management features to users, was accepted as the data storage platform of the big data system. Amazon EMR, Amazon SageMaker, and Amazon QuickSight were used for the step of data processing, data analysis, and visualization of the big data system respectively. We tested that the developed system could predict soil bulk density and able to replace a typical environmental model by using models based on machine learning and deep learning. The results of the two tests showed positive results that the developed models could predict soil properties and simulate natural phenomena as much as the typical environmental model could.  However, since the system is at an early development stage, it needs repetitive tests in the future considering various soil properties. If this system becomes fully functional, the system will be helpful to improve soil environments.
Process understanding of a linkage between East-Asian cold-surge wiith the unprecedented Arctic warming event in early 2016
Authors: Han Kwang-hee , Ku Ho-young , Kim Baek-min
Published: March 2020

At the end of December 2015, Storm Frank, a major Atlantic windstorm, intruded into the Arctic-circle along with warm air and a large amount of moisture, resulting in an unprecedented Arctic high-temperature phenomenon. In late January 2016, the Eurasian continent suffered a series of strong cold events. This study performed a synoptic analysis of a daily Northern Hemisphere SLP and 500hPa, 300hPa height anomaly using JRA-reanalysis data focusing on the process understanding of the sequential development and strengthening of Siberian high in association with the generation of the Ural blocking after the Arctic warming event. From synoptic analysis , we found that, within one month period, there exist several spells of Ural blocking occurrence instead of steady occupation of persistent high pressure over Ural Mountain region. The heat intrusion from midlatitude in association with Storm Frank caused a large wave breaking event over Atlantic sector of Arctic and initiated Ural blocking. The unprecedented warm temperature in early 10 days of January 2016 caused a large sea-ice loss and further heat injection from Barents/Kara seas helping anchoring the blocking over Ural Mountain region. In January 2016, several cold events over Eurasian continent well matched with the several spell of Ural blocking events. We suggest that daily scale interactions among warm advection, downward longwave radiation, sea-ice loss, and blocking occurrence need to be carefully considered to understand true nature of Arctic-Midlatitude linkage issue.
Asymmetric impact of CP ENSO on the significant reduction of tropical cyclone genesis frequency over the WNP since the late 1990s
Authors: Kim Han-Kyoung , Yeh Sang-Wook , Kang Nam-Young , Moon Byung-Kwon
Published: March 2020

Tropical cyclone (TC) genesis frequency over the western North Pacific (WNP) is reduced significantly since the late 1990s, coinciding with a Pacific decadal oscillation (PDO) phase change from positive to negative. In this study, the underlying mechanism for this reduction is investigated through analysis of asymmetric central Pacific (CP) El Niño-Southern Oscillation (ENSO) properties induced by the negative PDO phase. Results suggest that the significant reduction is caused by asymmetric CP ENSO properties, in which the CP La Niña is more frequent than the CP El Niño during negative PDO phases; furthermore, stronger CP La Niña occurs during a negative PDO phase than during a positive PDO phase. CP La Niña (El Niño) events generate an anticyclonic (cyclonic) Rossby wave response over the eastern WNP, leading to a significant decrease (increase) in eastern WNP TC genesis. Therefore, more frequent CP La Niña events and the less frequent CP El Niño events reduce the eastern WNP mean TC genesis frequency during a negative PDO phase. In addition, stronger CP La Niña events during a negative PDO phase reinforce the reduction in eastern WNP TC genesis. The dependency of CP ENSO properties on the PDO phase is confirmed using a long-term climate model simulation, which supports our observational results. 

Acknowledgements: This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT; No. 2019R1A2C1008549).
Ammonia, carbon dioxide and methane in Mediterranean paddy fields along the 2019 crop season
Authors: Estruch Carme , Curcoll Roger , Borrós Marta , Àgueda Alba , Morguí Josep-Anton
Published: March 2020

Human activities implying land management are potential sources of greenhouse gases (GHGs) such as carbon dioxide (CO2) and methane (CH4). In addition, agricultural management practices enhances the presence of reactive gases in the atmosphere such as ammonia (NH3).  Knowing the atmospheric variability of gases in relation to the different stages of the rice culture cycle and other anthropic activities could help to improve GHGs' mitigation strategies in deltas.

A mobile survey was undertaken through 2019 in the Ebro Delta as a part of the ClimaDat Network project (DEC station, www.climadat.es), to study the effect of land management in the spatial and temporal variability of greenhouse gases and NH3 concentrations. We are broadening the scope of a survey undertaken in 2012 (Àgueda et al. 2017). In the new survey we increased the total number of transects and longitude every three weeks during a year, starting in December 2018.

Whereas atmospheric NH3 concentration links with diurnal and seasonal cycles, the distribution of CO2 and CH4 shows a combination of spatial and temporal variability.   Our aim is to understand how we can use wind trajectories to find the principal sources of atmospheric variability. That is, can wind direction improve our comprehension of metabolic processes occurring in paddy lands? In this work, we use wind trajectories as means of spatial classification, to explore the spatiotemporal dynamic affecting the potential of CO2 and CH4 atmospheric concentration. 
Ionosphere VTEC modeling with the raw-observation-based PPP model：an advantage demonstration in the multi-frequency and multi-GNSS context
Authors: Liu Teng , Zhang Baocheng , Yuan Yunbin , Zhang Xiao
Published: March 2020

The ionospheric delay accounts for one of the major errors that the Global Navigation Satellite Systems (GNSS) suffer from. Hence, the ionosphere Vertical Total Electron Content (VTEC) map has been an important atmospheric product within the International GNSS Service (IGS) since its early establishment. In this contribution, an enhanced method has been proposed for the modeling of the ionosphere VTECs. Firstly, to cope with the rapid development of the newly-established Galileo and BeiDou constellations in recent years, we extend the current dual-system (GPS/GLONASS) solution to a quad-system (GPS/GLONASS/Galileo/BeiDou) solution. More importantly, instead of using dual-frequency observations based on the Carrier-to-Code Leveling (CCL) method, all available triple-frequency signals are utilized with a general raw-observation-based multi-frequency Precise Point Positioning (PPP) model, which can process dual-, triple- or even arbitrary-frequency observations compatibly and flexibly. Benefiting from this, quad-system slant ionospheric delays can be retrieved based on multi-frequency observations in a more flexible, accurate and reliable way. The PPP model has been applied in both post-processing global and real-time regional VTEC modeling. Results indicate that with the improved slant ionospheric delays, the corresponding VTEC models are also improved, comparing with the traditional CCL method.
Sensitivity of Arctic sea ice to variable model parameter space in Regional Arctic System Model simulations.
Authors: Osinski Robert , Maslowski Wieslaw , Lee Younjoo , Craig Anthony , Clement-Kinney Jaclyn , Niciejewski Jan
Published: March 2020

The Arctic climate system is very sensitive to the state of sea ice due to its role in controlling heat and momentum exchanges between the atmosphere and the ocean. However, the representation of sea ice state, its past variability and future projections in modern Earth system models (ESMs) vary widely. One of the reasons for that is strong sensitivity of ESMs to sea ice related varying parameter space. Based on limited observations, those parameters typically have a range of possible values and / or are not constant in space and time, which is a source of model uncertainties.   

The Regional Arctic System Model (RASM) is a limited-domain fully coupled climate model used in this study to investigate sensitivity of sea ice states to limited set of parameters. It includes the atmospheric (Weather Research and Forecasting; WRF) and land hydrology (Variable Infiltration Capacity; VIC) components sharing a 50-km pan-Arctic grid. The sea ice (the version 6.0 of Los Alamos sea ice model, CICE) and ocean (Parallel Ocean Program, POP) components share a 1/12° pan-Arctic grid. In addition, a river routing scheme (RVIC) is used to represent the freshwater flux from land to ocean. All components are coupled at high frequency via the Community Earth System Model (CESM) coupler version CPL7.

We have selected four parameters out of the set evaluated by Urrego-Blanco et al. (2016) and subject to their potential impact on sea ice and coupling across the atmosphere-sea ice-ocean interface. The total of 96 sensitivity simulations have been completed with fully coupled and forced RASM configurations, varying each parameter within its respective acceptable range. Using sea ice volume as a measure of sensitivity, the thermal conductivity of snow (ksno) parameter has produced the most sensitivity, in qualitative agreement with Urrego-Blanco et al. (2016). However, using dynamics related metrics, such as sea ice drift or deformation, other parameters, i.e. controlling the sea ice roughness and frictional energy dissipation, have been shown more important. Finally, different quantitative sensitivities to the same parameter have been diagnosed between fully-coupled and forced RASM simulations, as well as compared to the stand alone sea ice results.