bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution of residential wood burning to wintertime air pollution in an urban area
Authors: Kaltsonoudis Christos , Florou Kalliopi , Kodros John , Jorga Spiro , Vasilakopoulou Christina , Baliaka Charalampia , Aktypis Andreas , Nenes Athanasios , Pandis Spyros
Published: March 2021

Τhe composition of wintertime urban air in Patras, Greece was investigated during early 2020 focusing on the role of biomass burning. A high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a Proton Transfer-Reaction Mass Spectrometer (PTR-MS) were deployed. Additionally continuous measurements of the aerosol size distribution from 10 nm to 10 μm were performed, as well as measurements of the size-resolved aerosol composition using a Micro-Orifice Uniform-Deposit Impactor, black carbon (BC) concentrations using an SP2, aerosol absorption, brown carbon concentrations, and reactive oxygen species (ROS). A number of low-cost sensors for particles and vapors was also deployed in the city.

               The PM2.5 concentration peaked during the early evening reaching up to 150 µg m-3. PM1 aerosol (23 µg m-3 on average) was mainly composed of organics (69%) with the rest being BC (11%), sulphate (10%), nitrate (5%), ammonium (4%) and chloride (1%). Positive Matrix Factorization (PMF) of the measurements of the AMS indicated that biomass burning due to residential heating was the dominant source of PM1 during the campaign accounting for 53% of the total OA with the rest being the oxygenated organic aerosol (ΟΟΑ) at 25%, the cooking OA (COA) at 12% and the traffic related hydrocarbon-like OA (HOA) at 10%.

               The biomass burning contribution was also evident in several volatile organic compounds (VOCs) detected by the PTR-MS. Biogenic species such as isoprene and the monoterpenes showed clear relation to wood burning, while most of the aromatic compounds were related both to traffic and wood burning. The latter was also true for other gas species measured such as CO, NOx etc. Biomass burning was also a major contributor to the ROS measured as well as the brown carbon.
Assessing the influence of bedrock discontinuities on glacier fractures using ground-penetrating radar and structure from motion
Authors: Dematteis Niccolò , Trolio Fabrizio , Giordan Daniele
Published: March 2021

The Planpincieux Glacier lies in the Italian side of the Grandes Jorasses massif (Mont Blanc area), toward the Ferret Valley, in the Courmayeur municipality. This is a highly touristic area, visited every year by tens of thousands of people.

In summers 2019 and 2020, large portions of the Montitaz Lobe of the glacier (estimated volumes of 250000 m3 and 500000 m3 respectively) became unstable and menaced the Planpincieux village. According to runout simulations, such volumes could have reached and damaged a small bridge, buildings or the main valley road, depending on the volume involved in the collapse. Therefore, robust volume estimation was required for the realisation of effective safety plans.

To this aim, a helicopter-borne ground-penetrating-radar (GPR) survey was conducted in July 2020 with the novel dual polarization AIRETH system. Such a survey provided the ice thickness (20-60 ±10 m) of the unstable portion  and the bedrock topography along transects.

Besides, multiple helicopter and drone photogrammetric surveys were acquired since 2017, which provided the digital terrain model (DTM) and the orthophotos of the glacier using structure from motion (SfM) technique.

Merging GPR and SfM allowed at reconstructing the evolution of the glacier shrinkage in the period where DTMs were available. Moreover, it was possible to assess the correspondence of several bedrock discontinuities with large recurrent fractures.

Even though it is commonly acknowledged that the bedrock topography influences the glacier morphology, their correspondence has been rarely demonstrated in an Alpine glacier.

Since the fractures provoked by the bedrock discontinuities might destabilise the underlying glacier portion, the knowledge of the actual position of such fractures can help in the quantitative evaluation of the glacier instability. This can have a strong impact in the potential glacier-related risk assessment and management.
The rheology and mechanical anisotropy of a foliated blueschist
Authors: Tokle Leif , Hufford Lonnie , Morales Luiz , Behr Whitney
Published: March 2021

Blueschists are a major constituent rock type along the subduction zone interface and therefore critical to our understanding of subduction zone dynamics. Previous experimental work on natural blueschists focus on either seismic anisotropy or on the process of eclogization of a blueschist aggregate. We have begun an experimental investigation to constrain the rheology and mechanical anisotropy of a naturally foliated blueschist from the Condrey Mountain Window, CA, USA. General shear experiments were performed in a Griggs apparatus using cores of the natural blueschist at 700°C, 1 GPa, and a shear strain rate of ~10-5 s-1. The starting material consists of ~55% glaucophane, ~40% epidote, ~5% titanite, and <5% quartz where both glaucophane and epidote have strong crystallographic fabrics and shape-preferred orientations that define the foliation. Three types of experiments were performed: 1) with the foliation parallel to the shear plane, 2) with the foliation parallel to the sigma1 direction, and 3) where the starting material was crushed into a powder representing no foliation. Both of the foliated experiments achieve similar peak shear stresses of ~250 MPa; however, the sample with the foliation parallel to the shear plane shows strain weakening while the sample with the foliation parallel to the sigma1 direction shows no strain weakening. We also observe several stress drops of ~20-30 MPa in the sample with the foliation parallel to the sigma1 direction prior to peak stress conditions. Microstructures from both of the foliated samples show evidence for brittle deformation processes, while kinking is also commonly observed in glaucophane. The sample with no foliation has a lower shear stress of ~130 MPa and shows no evidence for brittle deformation processes but rather shows development of a S-C-C’ mylonitic fabric. Additional experiments will be performed at different temperatures and strain rate conditions. A detailed microstructural analysis will accompany the mechanical results.
Analysis of tropospheric parameter time series obtained with various types of GNSS antenna phase center models
Authors: Stępniak Katarzyna , Krzan Grzegorz
Published: March 2021

Water vapour is a key variable of the water cycle and plays a special role in many atmospheric processes controlling the weather and climate. Nowadays, extreme weather events, such as storms, floods, landslides, heat waves and droughts are the main concerns of society. The Global Navigation Satellite System (GNSS) is one of the few tools that can be used as an atmospheric water vapour sensor and, simultaneously, provide continuous, unbiased, precise and robust atmosphere condition information. A significant impact on the tropospheric parameter determination in the processing of satellite observations has undoubtedly GNSS antenna phase centers model.

Therefore, the aim of our study is to investigate the impact of different GNSS antenna calibration models on the quality of the tropospheric parameter series applied for climate applications. We analyse the zenith total delays (ZTD) obtained from GNSS data processing and afterwards converted integrated water vapour (IWV). Three years of GNSS data collected at 40 European Reference Frame (EUREF) Permanent GNSS Network (EPN) stations were processed with the NAPEOS software. Precise Point Positioning (PPP) technique utilizing European Space Agency (ESA) precise satellite orbits and clocks was used to estimate the parameters. Several different processing variants were processed and inter-compared. The first group of solutions was obtained by applying the International GNSS Service (IGS) type-mean Phase Center Correction (PCC) models. In the second and third groups of solutions, PCC models from respectively individual field robot calibration and calibration in an anechoic chamber were used. All solutions were processed using GPS and Galileo observations. Moreover, in order to validate and assess the quality of the GNSS solutions, the tropospheric parameters obtained from ERA5 reanalysis were compared with GNSS estimates. 

In general, the results of the study show that the NAPEOS software can provide high quality GNSS tropospheric delay time series. The initial results indicate that the impact of applying different PCC model calibrations is not negligible. ZTD estimates obtained from variants using ROBOT and IGS14 calibration are closer to ERA5 than estimates from variants that used calibrations in an anechoic chamber. In addition, multi-GNSS processing variants are closer to ERA5 than GPS only or Galileo only processing variants. The results also depend on the equipment (receiver and antenna) of the stations. Validation against the data from climate reanalysis confirms that all GNSS approaches provide high-quality ZTD estimates. Furthermore, there is a high agreement in the IWV distributions between GNSS and ERA5.
Characterizing volcanic tremor sources associated with collapses in Halema‘uma‘u Crater at the beginning of the 2018 Kilauea eruption
Authors: Soubestre Jean , Chouet Bernard , Dawson Phillip
Published: March 2021

We analyze data from one tiltmeter and twelve broadband seismic stations recorded at the beginning of the 2018 Kilauea eruption, to provide an integrated view of distinct tremor sources that preceded and accompanied this eruption. Studying the beginning of the eruption is challenging because of the diversity and complexity of signals that were recorded during this phase. But such undertaking represents a key aspect for understanding the dynamics of the different processes that took place at the start of the lava lake withdrawal on May 2 and during the twelve major collapses that occurred in Halema‘uma‘u Crater through May 26. The application of a network-based method to automatically detect and locate seismic tremor, combined with physical modeling of the underlying source processes, enables a characterization of these tremor sources in unprecedented detail.

Our analyses document one tremor source active during the period preceding the eruption, which is attributed to the quasi-steady radiation from a shallow hydrothermal system located at the south-southwest edge of Halema‘uma‘u Crater. These analyses further document two newly described sequences of gliding tremor. The first sequence is attributed to progressive jerky intrusions of a rock piston into a shallow hydrothermal reservoir between May 7 and May 17. The second sequence is attributed to the gradual degassing of a bubbly magma within an east striking dike below Halema‘uma‘u Crater, impacted by repeated roof collapses, and resulting in a quasi to totally degassed magma by May 26.
Quantifying past changes in Holocene ultraviolet-absorbing compounds (UACs) from Cedrus pollen in Lake Sidi Ali, Morocco, Africa based on fourier-transform infrared spectroscopy (FTIR)
Authors: Wang Tianyuan , Bell Benjamin , Fletcher William , Wogelius Roy , Zielhofer Christoph
Published: March 2021

UV-B radiation may affect atmospheric circulation and influence climate, as well as affecting all biological life on Earth. However, past environmental and climate reconstructions (using various multi-proxy approaches) generally do not focus on UV-B. Ultraviolet-Absorbing Compounds (UACs) in pollen grains are an indicator of the UV-B level received by plants, and it is possible to measure the abundance of UACs in pollen using Fourier Transform Infrared (FTIR) micro-Spectroscopy, providing a promising approach to UV-B reconstruction. This research reconstructed UAC levels in individual Cedrus atlantica (Atlas cedar) pollen grains within sediment samples from a 20 m core at Lake Sidi Ali, Middle Atlas, Morocco, spanning the Holocene. Correlations between UACs and other palaeoenvironmental proxies from the same core are discussed, including, oxygen stable isotopes (18O) which reflect winter rainfall, local dust sedimentation, and lake sediment CaCO3 and Total Organic Carbon (TOC), as well as independent 10Be-derived Total Solar Irradiance (TSI). Correlations between these proxies may indicate solar-related temperature and humidity fluctuations at Lake Sidi Ali, considering mechanisms of varied ocean and terrestrial circulation under different levels of solar activity, although there is some chronological uncertanty due to different sampling resolutions. A positive correlation between UAC levels and winter rainfall at Morocco implies connections between oceanic circulation and solar activity, while the relationship with local dust sedimentation reveals how solar irradiation may influence the Saharan dry air mass contribution to Morocco. Analysis of single pollen grains using FTIR presents several challenges in obtaining clean spectra, which can be a source of uncertainty with this approach. To minimise noise in FTIR spectra, Cedrus pollen grains should be measured using the same orientation under microscope. As this is not always posssible, we developed a protocol to evaluate spectra quality to filter out spectra that had excessive noise, or were deemed not to be a pollen grain. We also assess the minimum effective number of pollen grains that require measurement to provide a statisitcally significant sample and thereby improve the quality of UAC data. Our protocol represents good practice in developing a robust UAC data set, which can allow for UV-B and solar radiation levels to be inferred. Future work aims to quantitatively reconstruct UV-B levels using a modern UAC calibration.

 
Modelling the Tropospheric Multiphase Chemistry of Biomass Burning Trace Compounds Using the Chemical Aqueous Phase Radical Mechanism (CAPRAM)
Authors: He Lin , Hoffmann Erik Hans , Tilgner Andreas , Herrmann Hartmut
Published: March 2021

Biomass burning (BB) is a significant contributor to air pollution on global, regional and local scale with impacts on air quality, public health and climate. Anhydrosugars (levoglucosan, mannosan and galactocan) and methoxyphenols (guaiacol, creosol, etc.) are important tracer compounds emitted through biomass burning. Once emitted, they can undergo complex multiphase chemistry in the atmosphere contributing to secondary organic aerosol formation. However, their chemical multiphase processing is not yet well understood and investigated by models. Therefore, the present study aimed at a better understanding of the multiphase chemistry of these BB trace species by means of detailed model studies with a new developed detailed chemical CAPRAM biomass burning module (CAPRAM-BB). This module was developed based on the kinetic data from the laser flash photolysis measurements in our lab at TROPOS and other literature studies. The developed CAPRAM-BB module includes 2991 reactions (thereof 9 phase transfers and 2982 aqueous-phase reactions). By coupling with the multiphase chemistry mechanism MCMv3.2/CAPRAM4.0 and the extended CAPRAM aromatics (CAPRAM-AM1.0) and halogen modules (CAPRAM-HM3.0), it is being applied for some residential wood burning cases in Europe and wildfire cases in the US. Our model results show that the BB chemistry could significantly affect the budgets of important atmospheric oxidants such as H2O2 and HONO, and contribute to the SOA formation especially the fraction of brown carbon and substituted organic acids.
Solar Energetic Electron Events Associated with Hard X-ray Flares 
Authors: Wang Wen , Wang Linghua , Krucker Sam , Mason Glenn M. , Su Yang , Bucik Radoslav
Published: March 2021

We investigate 16 solar energetic electron (SEE) events measured by WIND/3DP with a double power-law spectrum and the associated western hard X-ray (HXR) flares measured by RHESSI with good count statistics, from 2002 February to 2016 December. In all 16 cases, the presence of an SEE power-law spectrum extending down to 65 keV at 1 AU implies that the SEE source would be high in the corona, at a heliocentric distance of >1.3 solar radii, while the footpoint or footpoint-like emissions shown in HXR images suggest that the observed HXRs are likely produced mainly by thick target bremsstrahlung processes very low in the corona. We find that in 8 cases (the other 8 cases), the power-law spectral index of HXR-producing electrons, estimated under the relativistic thick-target bremsstrahlung model, is significantly larger than (similar to) the observed high-energy spectral index of SEEs, with a positive correlation. In addition, the estimated number of SEEs is only ∼10-4 - 10-2 of the estimated number of HXRproducing electrons at energies above 30 keV, but also with a positive correlation. These results suggest that in these cases, SEEs are likely formed by upward-traveling electrons from an acceleration source high in the corona, while their downward-traveling counterparts may undergo a secondary acceleration before producing HXRs via thick-target bremsstrahlung processes. In addition, the associated 3He=4He ratio is positively correlated with the observed high-energy spectral index of SEEs, indicating a possible relation of the 3He ion acceleration with high-energy SEEs
Variability of natural whistler-mode emissions in the inner magnetosphere
Authors: Santolik Ondrej , Kurth William S. , Kletzing Craig A.
Published: March 2021

Whistler-mode electromagnetic waves, especially natural emissions of chorus and hiss, have been shown to transfer energy between different electron populations in the inner magnetosphere via quasi-linear or nonlinear wave particle interactions. Average or median intensities of chorus and hiss emissions have been found to increase with increasing levels of geomagnetic activity but their stochastic variations in individual spacecraft measurements at the same location are usually comparable to these large-scale temporal effects. Statistical properties of variations of wave power directly influence results of quasi-linear diffusion models.

We use the survey measurements of the Waves instruments of the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) onboard two Van Allen Probes to asses the probability distribution function of these stochastic variations. We take advantage of the entire data set of these measurements with a nearly 100% coverage from August 31, 2012 till October 13, 2019 (2600 days) for spacecraft A, and from  September 1, 2012 till July 16, 2019 (2510 days) for spacecraft B. 
Assessing policy coherence in the Water-Food-Ecosystems nexus
Authors: Arfa Imen , Blanco Maria , González-Rosell Adrián
Published: March 2021

To make coherent policies and strategies in the water-food system, it is necessary to analyse the synergies and trade-offs based on indicators approach. Policy coherence is considered a fundamental part of the EU’s contribution to achieving the sustainable development goals (SDGs) and calls for addressing the interlinkages between various SDGs. In this research, key indicators have been identified to analyse policy coherence within the water-food system in Andalusia (Spain). Furthermore, food and water policy scenarios have been simulated using a system dynamics model to evaluate future water-food trends by 2050. These provide a better understanding of how relevant policies are linked, which in turn helps to conduct integrated policy analyses and develop coherent policies and programmes across various dimensions of sustainable development.

In this region, water availability is a limiting factor for food production. Significant synergies and trade-offs were identified between water saving indicators and food production. An increase in water price causes a decrease in the irrigated area, as well as in irrigation water use. However, water pricing policies also increase crop irrigation water productivity. Agricultural policies that promote alternative sources of water, such as the reuse of treated wastewater, contribute to mitigating water scarcity, especially in the context of adaptation to climate change.
Skillful Dynamical-Statistical Predictions of European Summer Temperature
Authors: Mignot Juliette , Borchert Leonard , Koul Vimal , Mayer Björn , Menary Matthew , Sgubin Giovanni , Swingedouw Didier
Published: March 2021

While decadal North Atlantic sea surface temperature (SST) variations are generally predictable, prediction skill of surface temperature over Europe is much more limited. We invoke here observed links of decadal European summer temperature variations to North Atlantic SST changes in the preceding months to produce skillful decadal predictions of European summer temperature variations.

We analyze the ERA5 reanalysis data set to re-assess the observed influence of North Atlantic SST on European summer temperature for the period 1960-2020. To facilitate possible merging activities of initialized decadal prediction simulations and climate projections in the future, we examine predictions for the target regions Northern Europe (NEU), Central Europe (CEU) and Mediterranean (MED) as are defined as the SREX regions for IPCC Assessment Report 5. Summer (June-July-August: JJA) temperature in NEU shows significant co-variability in a decadal spectral band with MAM SST in the Western North Atlantic (WNA), while JJA CEU temperature shows the same with JJA SST in that region. JJA temperature in the MED region shows significant decadal co-variability with the annual mean AMV index. SVD analysis illustrates that an atmospheric Rossby wave train connects North Atlantic SST to European summer temperature changes.

Dynamical retrospective forecasts from a suite of decadal prediction systems from the Coupled Model Intercomparison Project Phase 6 Decadal Climate Prediction Project are tested for their agreement with observations for the period 1960-2020. Dynamical predictions of JJA temperature in NEU, CEU and MED are mostly not skillful at lead years 1-10 in the CMIP6 simulations. Most models do, however, show skill in the SST regions that are connected to these summer temperature variations, identified above. We use these SST predictions to drive a simple statistical model that rescales the variance of the SST predictions according to observed SAT variance in the target region. This dynamical-statistical prediction is shown to be skillful at lead years 1-10 for summer temperature in the SREX regions. This skill, however, relies on the skill of the models in predicting the respective SST index. Our work therefore indicates a promising avenue to produce skillful decadal climate predictions over land based on skillful predictions of the ocean.
Sluggish hydrodynamic escape of early Martian atmosphere with reduced chemical compositions
Authors: Yoshida Tatsuya , Kuramoto Kiyoshi
Published: March 2021

   Mars may have obtained a proto-atmosphere enriched in H2, CH4, and CO during accretion. Such a reduced proto-atmosphere would have been largely lost by hydrodynamic escape, but its flux is highly uncertain. To estimate the evolution of the proto-atmosphere of Mars correctly, an exact escape modeling including exact radiative balance and chemical processes is required partly because those reduced species and their photochemical products may act as an effective coolant that suppresses the escape of atmosphere. Here we develop a one-dimensional hydrodynamic escape model that includes radiative processes and photochemical processes for a multi-component atmosphere and apply to the reduced proto-atmosphere on Mars.

   Under the enhanced XUV flux suggested for young Sun, the escape flux decreases by more than one order of magnitude with increasing the mixing fraction of CH4 and CO  from zero to > 10 % mainly because of the energy loss by radiative cooling by these infrared active chemical molecules. Concurrently, the mass fractionation between H2 and other heavier species becomes to be enhanced. Given that the proto-Mars initially obtained > 10 bar of H2 and carbon species equivalent to 1 bar of CO2 was then left behind after the end of the hydrodynamic escape of H2, the total amount of carbon species lost by hydrodynamic escape is estimated to be equivalent to 20 bar of CO2 or more. Such a severe loss of carbon species may explain the paucity of CO2 on Mars compared to Earth and Venus. If the proto-Mars obtained > 100 bar of H2, the timescale for H2 escape exceeds ~100 Myr. This implies that an atmosphere with reduced chemical compositions allowing the production of organic matter deposits may have been kept on early Mars traceable by geologic records.
Gas-phase O3 reaction of dimethyl phthalate and diethylphthalate: a kinetic and product study
Authors: Antiñolo María , Baeza María Teresa , Jiménez Elena , Albaladejo José
Published: March 2021

Phthalates are chemical species widely used as plasticisers that are known to be absorbed by living organisms and negatively affect their health. Phthalates have been detected mostly indoors. For example, they have been measured in the gas phase, as part of particulate matter and on different surfaces in the form of dust.1-4 Although their presence in this kind of environments is well known and widely documented, there are scarce studies on their behaviour when they are in contact with tropospheric oxidants such as ozone (O3) or hydroxyl radicals.5-7

The aim of this work is to measure, for the first time, the kinetics of the gas-phase reaction of O3 with two phthalates: dimethyl phthalate (DMP) and diethyl phthalate (DEP). In a smog chamber at room temperature and atmospheric pressure, decay rates of DMF or DEF are measured by a Proton Transfer-Time of Flight-Mass Spectrometer (PTR-ToF-MS), while the O3 concentration is determined by Fourier Transform Infrared (FTIR) spectroscopy. Gas-phase products are also monitored by PTR-ToF-MS and secondary organic aerosol (SOA) formation is also evaluated by a Fast Mobility Particle Sizer. The impact on the indoor air quality of DMP and DEP will be discussed considering their atmospheric lifetime and the generated products.

REFERENCES: 1. Bornehag, C.G.; Lundgren, B.; Weschler, C. J.; Sigsgaard, T.; Hagerhed-Engman, L.; Sundell, J. Environ. Health Perspect. 2005, 113, 1399-404; 2. Rudel, R. A.; Perovich, L. J. Atmos. Environ. 2009, 43, 170‑181; 3. Fromme, H.; Lahrz, T.; Piloty, M.; Gebhart, H.; Oddoy, A.; Rüden, H. Indoor Air 2004, 14, 188-195; 4. Larsson, K.; Lindh, C. H.; Jönsson, B.A.; Giovanoulis, G.; Bibi, M.; Bottai, M.; Bergström, A.; Berglung, M. Environ. Int. 2017, 102, 114-124; 5. Mansouri, L.; Mohammed, H.; Tizaoui, C.; Bousselmi, L. Desalination Water Treat. 2013, 51, 6698-6710; 6. Mohan, S.; Mamane, H.; Avisar, D.; Gozlan, I.; Kaplan, A.; Dayalan, G. Materials 2019, 12, 4119 (3); 7. Dueñas Moreno, J.; Rodríguez S, J.L.; Poznyak, T.; Chairez, I.; Dorantes-Rosales, H.J. J. Environ. Manage. 2020, 270, 110863 (7).
Estimation of fracture compliance based on group delays inferred from full-waveform sonic log data
Authors: Zhou Zhenya , Caspari Eva , D. Barbosa Nicolás , Greenwood Andrew , Holliger Klaus
Published: March 2021

Fractures, which are ubiquitous in the Earth’s upper crust, have significant impacts on a wide range of human activities, and, hence, their adequate characterization is of wide interest and importance. Seismic methods have significant potential for effectively addressing this objective. When a seismic wave propagates across a fluid-filled fracture, its amplitude is diminished and its travel time is increased. Based on the linear slip theory, the associated amplitude decays and phase delays can be used to estimate the mechanical compliance of fractures. Full-waveform sonic (FWS) log data are particularly well-suited for this purpose. While the amplitudes of FWS data acquired during standard continuous logging runs (tool being moved uphole at a constant logging speed) can be somewhat unstable, the associated first-arrival travel times are generally quite robust. In this work, we exploit the relation between the time delay that seismic waves experience across fractures and relate them to the associated compliances. Specifically, we estimate fracture compliance from the differences in group time delay of the refracted P-wave between fractured and non-fractured sections along a borehole. Numerical simulations indicate that the proposed method provides reliable compliance estimates not only for individual fractures, but also for sets of multiple discrete fractures. This finding is corroborated by applying our approach to FWS log data acquired in the course of standard logging runs in the Bedretto Underground Laboratory (www.bedrettolab.ethz.ch). Our estimates are comparable to previously inferred compliance values in a closely comparable geological environment (Grimsel test site, www.grimsel.com). The latter were inferred under rather ideal conditions, involving the quasi-static acquisition of the FWS data as well as the combination of amplitude and travel time information for their interpretation. An interesting and important open question, which we plan to address in the following, concerns the influence of the heterogeneity of the host rock embedding the fractures on compliance estimation in general and on the proposed method in particular.
Evaluation of Earth Observation Products and Their Potential for Crop Damage and Crop Loss Assessment. The Case of Beacon Project.
Authors: Lekakis Emanuel , Tarquis Ana Maria , Kotsopoulos Stylianos , Mygdakos Gregory , Dimitrakos Agathoklis , Tsioutsia Ifigeneia Maria , Rivas-Tabares David , Simeonidou Polymachi
Published: March 2021

Agricultural Insurance (AgI) sector is expanding on a global scale and is projected to grow by €50 B, by 2020. This rapid growth is driven by a set of fundamental structural changes directly affecting the agricultural sector like more frequent and severe extreme weather events, growing global population and intensification of production systems. Insurance solutions are set to grow in importance for agricultural management, given that agriculture will continue to be increasingly dependent on risk financing support. However, the development and provision of insurance services/products in the agricultural sector is generally low as compared to other sectors of the economy, and in their majority, suffer from low market penetration.

In that frame, the BEACON toolbox was born, that aims to provide insurance companies with a robust and cost-efficient set of services that will allow them i) to alleviate the effect of weather uncertainty when estimating risk of AgI products; ii) to reduce the number of on-site visits for claim verification; iii) to reduce operational and administrative costs for monitoring of insured indices and contract handling; and iv) to design more accurate and personalized contracts. Specifically, BEACON scales-up on EO data and Weather Intelligence components, couples them with blockchain, to deliver the required functions for Weather Prediction and Assessment and Smart Contracts and offer the required services:

Crop Monitoring, which provides contract profiling and crop monitoring data together with yield estimations.

Damage Assessment Calculator, which supports AgI companies in better assess and calculate damage to proceed with indemnity pay-outs of claims.

Anti-fraud Inspector, which allows AgI to automatically check the legitimacy of a claim submitted.

Weather Risk Probability, which provides probabilities maps of extreme weather events that may occur in the upcoming season.

Damage Prevention/ Prognosis – Early Warning System, which provides extreme weather alerts to AgI providers and their customers.

This work focuses on the Damage Assessment Calculator component. It provides an approach using different types of EO data, implemented in the operational workflow of BEACON that can be used by AgI companies to improve the prediction and crop loss assessment due to drought and hailstorms.

 

Acknowledgements

This  project  has  received  funding  from  the  European  Union's Horizon 2020 Research and Innovation programme under grant agreement No 821964 (BEACON).
Bayesian spatiotemporal statistical modelling of water quality within rivers
Authors: Wilkie Craig , Ray Surajit , Scott Marian , Miller Claire
Published: March 2021

Rivers are vital parts of the hydrosphere, providing ecosystem services and water for drinking and agriculture. However, rapid industrialisation and urbanisation globally leads to increasing pollution in many rivers. On their own, many in-river monitoring efforts in lower middle income countries do not yet provide enough information to adequately understand the general state or trends in freshwater ecosystems, presenting difficulties in efforts to mitigate water quality degradation. However, new sources of data such as satellites, drones and sondes provide better spatial and temporal coverage of the river network. This talk presents a statistical downscaling approach for the fusion of data from these different sources into a single product with improved accuracy and coverage compared to that of an individual source, through a Bayesian hierarchical modelling approach. The model development is motivated by the Ramganga river in northern India, a source of irrigation for crops and drinking water that supports millions of people, but suffers from heavy metal and nutrient pollution from population pressures, intensive agriculture and industries along its length, leading to water quality degradation and biodiversity loss. The work takes place as part of the Ramganga Water Data Fusion Project, funded by the UK Global Challenges Research Fund with the aim of informing work such as risk-based modelling and developing future monitoring design to improve mitigation efforts.
Detection and Mapping of Forest Disturbance in Eurasian Continent
Authors: Zhang Yusha , Bo Yanchen , Sun Mei , Sun Tongtong
Published: March 2021

The global distribution and disturbance information of forest have strong impact on the change of Earth’s ecosystems. In the 1990s, the Eurasian continent forest cover an area of 182 million ha, accounting about 33.2% of the Eurasian continent land area. However, we lack a complete mapping of high-resolution forest disturbances in Eurasia. Remote sensing can regularly obtain forest cover data across expansive range. Therefore, a complete set of Landsat time-series-based forest disturbance detection method is constructed in this paper to map a 30-meter forest disturbance detection distribution map of Eurasian continent.

In the construction of Landsat time series(LTS) data, the Landsat TM, ETM +, and OLI images of forest growth season were selected and synthesized into inter-annual time series over 35 years from 1986 to 2020. And the appropriate indices, NBR and NDVI, were selected as the input data for time series analysis. In time series analysis, the adaptive threshold of model learning is effectively applied in the process of extracting potential disturbance points, and the rich temporal information of LTS is fully mined to optimize and filter the disturbances.

The LTS images and forest disturbance based on adaptive threshold model are used to map three decades of forest disturbances, including the characteristics of the disturbance, spatiotemporal distribution and disturbance frequency across Eurasian continent. The derived disturbance year maps revealed that the disturbed forest area is 237 million ha and 12.8% of Eurasia’s forest area. In order to validate the accuracy of the map, 10066 interpreted Landsat pixels, including 3932 disturbed samples and 6134 undisturbed samples, are selected as reference data. The overall accuracy of the disturbance map is 86.6%, with a commission error of 13.4% and an omission error of 9.4%. The results indicated that the LTS and adaptive threshold model can effectively support the mapping of forest disturbance in Eurasian continent.
Long-term rewetting of fen peatlands alters the response of water tables to rainfall and temperature
Authors: Ahmad Sate , Liu Haojie , Alam Shajratul , Günther Anke , Jurasinski Gerald , Lennartz Bernd
Published: March 2021

Fens belong to the most threatened ecosystems in Europe. Maintaining a high water table through rewetting is an effective measure to rehabilitate many of their ecosystem functions. However, the impact of meteorological factors such as relative humidity, precipitation and air temperature on water storage and its dynamics is still unclear especially for rewetted fens in the temperate regions. Here, we quantify the impact of meteorological factors on water table dynamics comparing a drained and a rewetted fen in North-East Germany, using multiple linear regression with data from continuous high-resolution (temporal) water level monitoring and weather stations. We found that a 1-degree rise in daily maximum air temperature causes a drop of about 4 mm in the water table in the drained and degraded fen but only a drop of around 2 mm at the rewetted site, mainly through evapotranspiration. Higher minimum relative humidity limits evapotranspiration and is, thus, negatively associated with water table elevation at both sites. Precipitation contributes to recharge, causing the water table to rise almost six times higher at the drained site than at the rewetted site. We attribute the differential impacts of meteorological factors on water table dynamics to (1) differences in vegetation, which acts as surface control and (2) differences in soil properties. We found that for the depths at which the groundwater fluctuates, the peat of the rewetted fen has a higher specific yield compared to the drained fen, causing the water table to rise or recede at smaller rates. A period of 20 years of rewetting was sufficient to form a new layer of organic matter with a substantial fraction of macropores providing water storage capacity and thereby changing water table response. Our study underlines the importance of long-term rewetting and meteorological factors for peatland restoration. Continuous monitoring of water table and vegetation development in rewetted fens is advisable to ensure long-term success, especially under climate change conditions.
Ionosonde and satellite data analysis in relation to the M5.9 April 6, 2009 L’Aquila (Italy) earthquake
Authors: Sabbagh Dario , Perrone Loredana , De Santis Angelo , Campuzano Saioa A. , Cianchini Gianfranco , Marchetti Dedalo , Orlando Martina , Piscini Alessandro , Soldani Maurizio
Published: March 2021

A combined ground-satellite study of the ionospheric response to the preparation phase of the M5.9 crustal earthquake occurred in L’Aquila (Italy) on April 6, 2009 is here presented. Ionospheric anomalies based on ionosonde observations of the altitude and blanketing frequency of the E-sporadic (Es) layer (h’Es and fbEs, respectively) and of the critical frequency foF2 of the F2 layer are considered. For our analysis we make use of data from the Rome ionospheric observatory, located 90 km away from the earthquake epicentre, looking for anomalies up to a couple of months before the mainshock occurrence. Specifically, the variations for 2-3 hours of these parameters with respect to the past 27-day hourly running median are studied in relation to: (a) the ongoing geomagnetic activity during and several hours before the detection of the anomalies, as described by the values of the global ap and the auroral AE geomagnetic indices; (b) the earlier-obtained empirical relations for the seismic-ionospheric disturbances relating the earthquake magnitude with the epicentral distance and the anticipation time of the found anomalies. In addition, ionospheric anomalies in the electron density measured over the earthquake preparation region by the CHAllenging Minisatellite Payload (CHAMP) satellite at altitudes of about 320 km are studied in relation to the ionosonde-derived anomalies during the whole period preceding the mainshock occurrence.
DisCoord: a serious game for co-creating knowledge for Disaster Risk Reduction
Authors: Delima Gina , Jacobs Liesbet , Loopmans Maarten , Ekyaligonza Mary , Kabaseke Clovis , Kervyn Matthieu , Mertens Kewan
Published: March 2021

Effective disaster risk reduction (DRR) presupposes awareness among key stakeholders on the causal factors that exacerbate disaster risks as well as a feeling of ownership over proposed DRR measures. Yet, the prevailing top-down communication of risk and the expert-centered knowledge have a limited impact in bringing significant positive change. Serious games respond to the need for a community-based DRR approach as they encourage a collective recognition of societal issues and co-learning at the different levels of the DRR governance system. However, there is still a gap in understanding how serious games facilitate co-creation of knowledge. In this article, we first introduce a serious game, called DisCoord, as a public pedagogy tool that bridges diverse views and sets of knowledge of DRR stakeholders separated by spatial and socio-cultural domains. Second, through a qualitative method of analysis of the 10 game sessions in Uganda, we examine the factors and processes that influence knowledge co-creation. The game actors – game designers, game facilitators and players – primarily steer and influence the co-creation process. These actors have diverse pre-game views, which are expressed through the game rules, arguments, game strategies, and game outcomes, and are confronted within the public space provided by the game. We find that crises experienced during the game, real-life based arguments provided by the players and own interpretations by the players are key factors in the co-creation process. This study leads us to conclude that games like DisCoord are useful as public pedagogy intervention as they bring different forms of knowledge together in a public space and facilitate co-learning. This paper also contends that countering a top-down approach of risk communication using a public pedagogy approach requires an openness towards the unpredictable, de-centered DRR, and plural co-learning outcomes.
Ubiquity of quasi-aerosol layers in the free troposphere over the Indian region: Results from multiyear satellite observations 
Authors: Kumar Gaurav , Vernier Jean Paul , Madhavan Bomidi Lakshmi , Ansari Kamran , Sinha Puna Ram
Published: March 2021

Vertical distribution of aerosols and their composition in the lower troposphere is critically important for assessing the Earth’s radiation budget and their impact on monsoon circulation. We combine the extinction coefficient, particulate depolarization ratio obtained from CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) for period of 11 years (2008-2018) over the Indian region to provide an unprecedented climatological overview of the physical and optical characteristics of quasi-aerosol layers and their source and formation mechanism throughout its annual life cycle in the free troposphere. The key findings includes: i)The quasi aerosol layer over the Indian region are found to be persistent between 4-6 km during all seasons and occasionally reach above 6 km and exhibited strong seasonal and regional dependency, ii) Layer thickness varies between 2.0 -3.0 km corresponds to primary peak are more frequent of about 80-90 % of cases over all six regions and while  secondary layer occasionally forms (10-20 %), iii) The aerosol layer thickness increases by about 36.7 and 25% during summer and fall season compared to that of spring, and winter, iv) Layer-AOT showed year-to-year variations of up to a factor of two with a relative variability of about 15-23% (1σ), v) Trend in layer AOT is not very conspicuous and showed oscillatory pattern, vi) Depolarization ratios generally increase with height suggesting that the irregularity of aerosol shape increases with altitude, vii) The polluted dust and smoke are the major aerosol components of the observed quasi aerosol layer  between 4 to 6 km for spring and fall season while these are the polluted dust during winter and summer.
The Irminger Sea – air-ice-ocean interactions in a 5 km coupled simulation with ICON-ESM
Authors: Gutjahr Oliver , Jungclaus Johann H. , Brüggemann Nils , Haak Helmuth , Marotzke Jochem
Published: March 2021

Recent observations suggest that deep convection and water mass transformation in the Irminger Sea southeast of Greenland, together with overflows from the Nordic Seas, may be more important for the variability of the Atlantic meridional overturning circulation (AMOC) than the Labrador Sea. The preconditioning for and triggering of deep convection in the Irminger Sea is strongly associated with topography-induced mesoscale wind phenomena, such as Greenland tip jets, katabatic winds and marine cold air outbreaks. However, the resolution of current coupled climate models is too coarse to capture all the properties of these wind systems or to capture them at all. Here we explore the air-ice-ocean interactions induced by mesoscale wind phenomena in the Irminger Sea in a 1-year global coupled 5km simulation with ICON-ESM. The model is able to capture the complex interactions of the wind field and the ocean. We find that strong downward katabatic winds cause substantial heat loss from the Irminger Sea in addition to Greenland tip jets. The outflowing katabatic winds form narrow streaks of cold air that extend across the entire Irminger basin from southeast Greenland to Iceland. In addition, cold air outbreaks from the sea ice lead to the genesis of mesoscale cyclones, which in turn can cause Greenland tip jets before moving off to the east. All these wind phenomena cause substantial heat loss that preconditions the ocean for deep convection. If these wind systems are not resolved, the water mass transformation in the Irminger Sea could be too weak, contributing to why the Labrador Sea dominates AMOC variability in models. We conclude that resolving these mesoscale wind systems in an Earth system model could have significant implications for deep convection and water mass transformation in the Irminger Sea, and thus for AMOC variability.