bluuebunny/crossref_metadata_2025 huggingface dataset:
Future fire impact on PM2.5 pollution and attributable mortality
Authors: Park Chaeyeon , Takahashi Kiyoshi , Fujimori Shinichiro , Li Fang , Phung Vera Ling Hui , Takakura Junya , Hasegawa Tomoko , Ito Ahihiko
Published: March 2022

Fine particulate matter with a diameter of ≤ 2.5  (PM2.5), one of the hazardous air pollutants, contributed 4.5 million to 8.9 million global mortality annually. Among the total PM2.5 related mortality, 5%–21% were attributed to fires. While anthropogenic fire has been declined by reduced land fragmentation and changed land use, climate change has increased fire activities especially in fire seasons. These fires eventually lead to high PM2.5 in many regions, leading to public health concern. However, the impact of future fires on PM2.5 and its health burden according to climate change and socioeconomic scenarios has not been studied globally. We estimated fire related PM2.5 at the end of 21st century under various future scenarios (combination of Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs)) and its attributable mortality. We used modified CLM and GEOSChem for simulating fire emissions and PM2.5 concentration, respectively. The Global Burden of Disease (GBD) method was used for estimating attributable mortality. We also evaluated how global inequality in fire-PM2.5 mortality by income (economic inequality) would change. We found that future climate change led to higher fire-PM2.5 by increasing drought and biomass carbon density, whereas future increased GDP would offset the increase in fire-PM2.5. The results of fire-PM2.5 mortality varied significantly by SSPs. Population increase under SSP3 would lead to increase in mortality and economic inequality. The total fire-PM2.5 mortality decreased under SSP1–4, but the economic inequality increased under SSP4. If the world follows SSP1-RCP2.6 scenario, fire-PM2.5 mortality would reduce about 40% and improve economic equality.

This research was supported by the Environment Research and Technology Development Fund (JPMEERF20202002) of the Environmental Restoration and Conservation Agency of Japan.
Rifted margins classification and forcing parameters
Authors: Sapin Francois
Published: March 2022

Rifted margins are the result of the successful process of thinning and breakup of continents leading to the formation of new oceanic lithosphere. Observations on rifted margins are now integrating an increasing amount of multi-channel seismic data and drilling of several Continent-Ocean Transitions. Based on large scale geometries and domains observed on high-quality long-offset seismic lines, we illustrate a simple classification based on mechanical behavior and magmatic production. Therefore, rifted margins are not divided into opposing types, but described as a combination and continuum that can evolve through time and space from ductile to brittle mechanical behavior on one hand and from magma-poor to magma-rich on the other hand.

For instance, margins such as the Mauritania-Senegal Basin evolve north to south from a magma-poor to a magma-rich margin. Margins such as the Vøring one suffered different rifting episodes evolving from ductile deformation in the Devonian to more brittle and magma-poor rifting in the Cretaceous prior to a final magma-rich breakup in the Paleogene.

Thanks to these examples and to some others, we show the variability of the rifted margins worldwide but also along strike of a single segment and through time along a single margin in order to explore and illustrate some of the forcing parameters that can control the initial rifting conditions but also their evolution through time.
Seismica: a community-led Diamond Open-Access journal for seismology and earthquake science
Authors: Gabriel Alice-Agnes , Bruhat Lucile , van den Ende Martijn , Funning Gareth , Hicks Stephen P , Jolivet Romain , Lecocq Thomas , Rowe Christie
Published: March 2022

Seismica is an effort to establish a Diamond Open-Access (OA) journal for the community of researchers working in the (broadly defined) fields of seismology and earthquake science. Diamond OA journals are free to read, do not charge authors to publish, and thus promise to widen access to published research to all. Such efforts require broad community participation beyond editing and reviewing articles, as all functions typically fulfilled by paid staff, including administration, production, typesetting and copy editing, must be undertaken by volunteers.

In December 2020, the Seismica Task Force, a spontaneously-organized group of seismologists and earthquake scientists, connected on Twitter. Inspired by the example of the established Diamond OA journal Volcanica, we began to explore the possibility of founding such a journal in our own field. Through outreach via social media, blog posts, conference presentations and disciplinary mailing lists, we have built a community of over 180 interested participants. With broad input, this group has developed a roadmap (https://doi.org/10.31223/X5304V) for the build-out of the journal, including an editorial structure and policies, broad outreach and structures to ensure a diverse editorial team, a logo and visual branding, and agreements with the McGill University Library to host and support the journal.

In this presentation, we will introduce our first editorial board, and solicit our first article submissions for publication in 2022.  We will also update the broader community on these and other developments in the journal-building process, and share our experiences and lessons learned.
Cross helicity of interplanetary coronal mass ejections
Authors: Good Simon , Hatakka Lauri , Ala-Lahti Matti , Soljento Juska , Osmane Adnane , Kilpua Emilia
Published: March 2022

Like the solar wind in general, interplanetary coronal mass ejections (ICMEs) display magnetic field and velocity fluctuations across a wide range of scales. These fluctuations may be interpreted as Alfvénic wave packets propagating parallel or anti-parallel to the local magnetic field direction, with cross helicity, σc, quantifying the difference in power between the counter-propagating fluxes. We have determined σc at inertial range frequencies in a large sample of ICME flux ropes and sheaths observed by the Wind spacecraft at 1 au. The mean σc value was low for both the flux ropes and sheaths, with the balance tipped towards the positive, anti-sunward direction. The low values indicate that Alfvénic fluxes are more balanced in ICMEs than in the solar wind at 1 au, where σc tends to be larger and anti-sunward fluctuations show a greater predominance. Superposed epoch profiles show σc falling sharply in the upstream sheath and being typically close to balance inside the flux rope near the leading edge. More imbalanced, solar wind-like σc values are found towards the trailing edge and further from the rope axis. The presence or absence of an upstream shock also has a significant effect on σc. Coronal and interplanetary origins of low σc in ICMEs are discussed.
Integral fluences of GLEs: A new full reconstruction
Authors: Usoskin Ilya , Koldobskiy Sergey , Kovaltsov Gennady
Published: March 2022

For many reasons, from solar physics to terrestrial and engineering applications, it is important to estimate the total fluences of solar energetic particles (SEPs) especially for the strongest hard-spectrum events known as ground-level enhancements (GLEs). Here we present a revised reconstruction of the SEP spectral fluences using a recently developed probabilistic Monte-Carlo method, applied to major GLE events of the last decades. The method utilizes data from the ground-based neutron-monitor network in the higher-energy range and revised space-borne/ionospheric data for the lower-energy part. The fluences are reconstructed along with realistic uncertainty estimates which appear large for weak events and small for strong events.
b-value and kinematic parameters from 3D focal mechanisms distributions in Southern California
Authors: Carducci Andrea , Petruccelli Antonio , De Santis Angelo , de Nardis Rita , Lavecchia Giusy
Published: March 2022

The frequency-magnitude relation of earthquakes, with particular attention to the b-value of Gutenberg-Richter law, is computed in Southern California. A three-dimensional grid is employed to sample relocated focal mechanisms and determine both the magnitude of completeness and the b-value for each node. Sampling radius and grid size are appropriately chosen accordingly to seismogenic source dimensions. The SCEC Community Fault Model is used for comparison of the main fault systems along with the calculated 3D distributions.

The b-values are compared to Aλ, a streamlined kinematic fault quantification, which does not use inversion processes since directly depends on individual rakes of focal mechanisms. Potential relationships between the two quantities are then computed through multiple regressions at increasing depth ranges: they may help to evaluate seismic hazard assessment in relating the frequency and size of earthquakes to kinematic features. The rheological transition from elastic to plastic conditions is computed, assuming different physical constraints, and its influence on b-value and Aλ is also analyzed. Among proposed linear, polynomial, and harmonic equations, the linear model is statistically valued as the most probable one to relate the two parameters at different depth ranges. b-values against Aλ results are implemented into a 3D figure, where point data are interpolated by “Lowess Smoothing” surfaces to visually check the constancy depending on depth.
Gravimetric quasi-geoid of the Baltic Sea and comparison to GNSS levelling, DTU21 and tide gauges
Authors: Teitsson Hergeir , Forsberg René
Published: March 2022

A gravimetric quasi-geoid model, based on the latest FAMOS database release, has been computed for the Baltic Sea region, aiming for a best-possible model on the sea, while not focusing on the surrounding land.

 The geoid computation is based on the FFT remove-compute-restore method. XGM2019 is used as global reference field, with a Wong-Gore linear tapering from 180 to 200. No terrain corrections are included in the computation, since these are not expected to contribute to the accuracy of the model on the sea.

The gravimetric quasi-geoid model is compared to a GNSS-levelled ITRF2008 zero-tide dataset, the altimetry based DTU21 Mean Sea Surface dataset, and to a few tide gauge stations distributed throughout the region. Some preliminary comparisons to the GNSS-levelling dataset indicates that the gravimetric geoid has an accuracy of ±25 mm in the region surrounding the Baltic Sea.
An in-flow sensor system for data acquisition in snow avalanches
Authors: Neurauter Rene , Neuhauser Michael , Blobel Johannes , Winkler Robert , Dressler Falko , Fischer Jan-Thomas , Gerstmayr Johannes
Published: March 2022

The dynamics of snow avalanches and in particular their rheology is of big importance to develop improved avalanche models and thus increase safety in mountainous areas. Existing measurement systems only allow a limited in situ view of the dynamics of snow avalanches and therefore demand the development of innovative measurement systems. Furthermore, due to the limited measurement capability of existing systems, comprehensible motion reconstruction is currently not possible. Therefore, the aim of this work is to present a measurement system that enables accurate in flow observations of snow avalanches and has the mechanical properties of a typical snow granule. A main objective of the measurement system is to allow a full motion reconstruction regarding translations and rotations with a high sampling rate and without exceeding sensor ranges.

The newly developed system, denoted as AvaNode, has the shape of a concave cube with a variable density to fit typical snow granules in flowing avalanches and their deposits. The AvaNode contains a strapdown inertial navigation sensor capable of measuring accelerations, angular velocities, and magnetic flux densities with up to 400Hz and allows for an estimation of the orientations, velocities, and positions of the AvaNode using state of the art motion reconstruction algorithms. The reconstruction is significantly improved due to precise calibration of all sensors using reference measurements with a 6R robot and onsite magnetic field calibration. In order to get a refined motion trajectory, the AvaNodes are also equipped with radio ranging modules. These modules allow performing time of flight (TOF) measurements, determining the distance between several nodes. A Global Navigation Satellite System (GNSS) module determines longitude, latitude, and altitude, as well as world time, however, with low frequency resolution and larger errors due to snow coverage. To measure the temperature evolution in avalanches, an infrared temperature sensor is attached.  Multiple recovery systems like Recco rescue reflector (passive), Pieps TX600 (active), and Lambda4 Smilla (active) are integrated to allow fast retrieval of the sensors.

As first results, we present the employed sensor calibration approaches for the inertial navigation with corresponding laboratory data signatures. The sensor calibration allows in-depth analysis of motion data, identifying typical data signatures observed in avalanches. Furthermore, we show first data acquired from in-flow snow avalanche measurements, which prove the functionality of the system and allow the first insights into trajectories of snow granules, regarding accelerations, angular velocities, rotations, and position.
Testing potential mitigation measures to reduce nutrient loads to a temporary river
Authors: De Girolamo Anna Maria , Lo Porto Antonio
Published: March 2022

To achieve and maintain the good ecological status of surface waters, each EU Member State is expected to invest economic resources in a programme of measures. To do this, a preliminary analysis to quantify the anthropogenic pressures and their impacts on surface waters is necessary to prioritise the measures to be undertaken.

The objectives of this work were to: (i) quantify the nutrient loads from point and diffuse pollution to the Rio Mannu stream identifying the critical time in terms of water quality, and (ii) simulate some mitigation measures for reducing the nutrient loads being delivered to the wetland. Two “measures” were tested to mitigate nutrient pollution in high flow and low flow conditions: (1) the use of treated wastewater from urban wastewater treatment plants (WWTPs) for the irrigation of cultivated olive trees and a (2) reduction in fertiliser usage rates (20%).

Results showed that under high flow conditions, NO3-N and TP loads accounted for 89% and 99% of the total load, respectively. The low flow contribution to the total load was very low, with NO3-N and TP accounting for 2.8% and 0.7%, respectively. However, the natural hydrological regime in the study area is intermittent, and low flow represents a critical condition for the water quality due to the high concentrations of TP and NO3-N from WWTP discharge. Results indicated that agriculture is the main source of NO3-N in the surface waters. The point sources made a minor contribution, in terms of nutrient load to the surface waters, but they constitute a relevant hydrological pressure for the Rio Mannu, producing a shift from an intermittent hydrological regime (natural conditions) towards a perennial regime. The measures are effective to reduce nutrient loads in surface waters at the outlet for all hydrological conditions. Under high flow conditions, the reduction was 9% and 12% for NO3-N and TP loads, respectively. The reduction increased under normal and low flow conditions (75% and 83% for NO3-N and TP loads, respectively).

Based on this study, it is evident that a “programme of measures” for improving the current status of surface waters must be oriented towards reducing nutrient loads, both under high and low flow conditions. The results show that a 20% reduction in fertiliser usage on the main crops in this area, and the reuse of wastewater from selected WWTPs, would result in a significant reduction in the nutrient loads delivered to the wetland, although this reduction is not large enough, and supplementary measures would be required.
Large-scale siting of sand dams: a participatory approach and application in Angolan drylands
Authors: Piemontese Luigi , Castelli Giulio , Limones Natalia , Bresci Elena
Published: March 2022

Sand dams are simple and effective structures built across ephemeral riverbeds in arid/semi-arid regions to harvest water within sand pores and increase water availability and quality for rural communities. The complex morphological, hydrological, social and economic conditions that make sand dams a beneficial tool for water resilience are largely influenced by the siting phase. Proper location of a sand dam can reduce community’s travel time to water points, reduce water conflicts and increase food security through expansion of irrigated agriculture. On the other hand, a misplacement of sand dams can, at worst, increase disparities in water access and increase local conflicts. To approach a viable siting of sand dams, most projects are developed and delivered with the community through a bottom-up approach. However, in case of large-scale project, remote sensing and biophysical analysis are the dominant approach, leaving the socio-economic component at the margins of the siting strategy and eventually affecting the benefits to local communities. In this paper, we propose a large-scale participatory methodology to sand dams siting, which draws on mixed-methods connecting the conventional top-down biophysical analysis with bottom-up participatory research. We first describe the generic approach developed for sand dams siting in Namibe, a semi-arid region of South-west of Angola, then we draw on our case to propose a generic approach to large-scale participatory siting beyond Namibe.
Monitoring Gravel Volume Change by Very High Resolution Satellite Image Stereopairs
Authors: Lin Li-Shan , Tseng Kuo-Hsin
Published: March 2022

Taiwan is located on the convergent boundary of the Philippine Sea Plate and the Eurasian Plate. Due to the active orogenic movement, the rock formations are fragmented and the weak joints are developed. In recent years, heavy rainfall accompanied with the occurrence of river surges carry a large amount of broken sand and gravel to the downstream. The accumulation of a large amount of sand and gravel in the river may threaten the safety along the river bank, such as channel diversion and flooding. Therefore, the river channel needs to be dredged regularly to reduce the risk to the residents and properties. Because the dredging area is scattered and difficult to reach, on-site measurement has become a time-consuming and labor-intensive method. With the improvement of satellite technology, it is feasible to use efficient remote sensing technology to generate point clouds and a surface elevation model (DSM) for monitoring purposes. However, several problems still exist in this technology, including the scatteredness of control points and feature points, instability of the platform, varying imaging conditions, and time differences in the matching process. To solve the DSM errors caused by these problems, this study uses 3-D point cloud registration method to align the horizontal and vertical directions and tries to reduce elevation system error due to the failure of co-registration. First, feature description, extraction, and feature matching are performed. Second, the iterative closest point algorithm (ICP) is used to closely match two sets of point clouds after coarse alignment. Finally, elevation difference between two dets of DSM is verified with ground measurement data and the accuracy of the point cloud registration is assessed. We use a dredging area in Laonong River, Taiwan, as an example to monitor gravel volume change in river channel by high resolution Pléiades images and UAV in different time periods. Our preliminary results show that the spaceborne technology could achieve submeter level accuracy in monitoring height changes in each transect.
Long Time Steps for Advection: MPDATA with implicit time stepping
Authors: Weller Hilary , Woodfield James , Kuehnlein Christian , Smolarkiewicz Piotr
Published: March 2022

Semi-Lagrangian advection schemes are accurate, efficient and retain accuracy and stability even for large Courant numbers, but are not conservative. Flux-form semi-Lagrangian schemes are conservative and used to achieve large Courant numbers. However, this is complicated and would be prohibitively expensive on grids that 
are not topologically rectangular. 

Strong winds or updrafts can lead to localised violations of Courant number restrictions which can cause a model with explicit Eulerian advection to crash. Schemes are needed that remain stable in the presence of large Courant numbers and general grids, while the accuracy in the presence of localised large Courant numbers may not be so crucial.

Implicit time stepping for advection is not popular in atmospheric science because of the cost of the global matrix solution and the phase errors for large Courant numbers. However, implicit advection is simple to implement (once appropriate matrix solvers are available) and is conservative on any grid structure and can exploit improvements in solver efficiency and parallelisation. This talk will describe an implicit version of the MPDATA advection scheme and show results of linear advection test cases. To optimise accuracy and efficiency, implicit time stepping is only used locally where needed. This makes the matrix inversion problem local rather than global. With implicit time stepping MPDATA retains positivity, smooth solutions and accuracy in space and time.
Seasonal dynamics of active and passive chlorophyll fluorescence in a mountain Scots Pine (Pinus sylvestris L.) forest
Authors: Schwarz Michaela , Hammerle Albin , Julitta Tommaso , Migliavacca Mirco , Wohlfahrt Georg
Published: March 2022

Solar energy absorbed by chlorophyll molecules of plants is either used for the carboxylation of CO2 (i.e. photosynthesis), dissipated (in a regulated and unregulated fashion) as heat or re-emitted at higher wavelengths as fluorescence. Proximal or remote sensing measurements of the so-called sun-induced chlorophyll fluorescence (SIF) are thus thought to offer a non-obtrusive approach for quantifying a key ecosystem carbon cycle component and metric of plant health, gross primary productivity (GPP). 

In contrast to SIF, which is a relatively new approach, active measurements of chlorophyll fluorescence using the pulse amplitude modulation (PAM) technology represent a well-established standard approach. Up to date, few studies have combined active and passive (i.e. SIF) chlorophyll fluorescence measurements and the link between active chlorophyll fluorescence metrics and SIF is thus poorly understood, hampering progress in the physiological interpretation of the SIF signal.

The overarching goal of this study is to improve our physiological understanding of the SIF signal. To this end we jointly quantified ecosystem-scale passive (i.e. SIF) and leaf-scale active chlorophyll fluorescence. Measurements were conducted during the vegetation period (March to November 2021) at a mountain Scots Pine (Pinus sylvestris L.) forest close to the village of Obermieming (Austria). 

Two sets of automated PAM fluorometers (MoniPAM, Walz, Germany) were installed from a walk-up tower to measure active leaf-scale chlorophyll fluorescence (ChlF) on branches in the sunlit top of the canopy and in the more shaded sub-canopy zone of the forest. Additionally, SIF at the canopy scale was measured via a high-resolution spectrometer system (FloX, JB Hyperspectral Devices, Germany) and the eddy covariance method was used to determine net ecosystem CO2 exchange.

Preliminary results show an increase of SIF yield (SIF/aPAR) with warming temperature throughout summer followed by a steady decrease starting in autumn. A major heatwave event in June resulted in a decrease of the SIF and PSII yields, leading to an increase in NPQ. An overall decrease of PSII efficiency for shaded leaves compared to sun-exposed ones was detected, with significant reductions throughout decreasingly colder days in spring and autumn for both groups. Shaded leaves responded with an overall higher investment into NPQ mechanisms. In contrast, an increased yield of ﬂuorescence and constitutive thermal energy dissipation (f,D) in sun-exposed leaves could indicate higher heat dissipation for the exposed group.

Further analyses will use active chlorophyll fluorescence metrics for studying seasonal variability in SIF and SIF yield and their relationship to ecosystem-scale GPP.
Reassessing the influence of Sea Surface Temperature change on coral reef development on the Queensland Plateau during the Late Miocene. 
Authors: Petrick Benjamin , Reuning Lars , Auer Gerald , Auderset Alexandra , Zhang Yige , Wang Xingchen , Schwark Lorenz , Pfeiffer Miriam , Martínez-Garcia Alfredo
Published: March 2022

The loss of coral reefs in the past is not well understood with a number of theories proposed for their loss and expansion. The Queensland Plateau has one of the best-established coral histories. It is known that coral reefs were first established in the Early Miocene. These reefs then disappeared between 11-6 Ma during the Late Miocene but reestablished around 3.6 Ma. The loss of the reefs has often been tied to cool nutrient rich water during the Late Miocene where as the reestablishment of the reefs have been tied to increases in warmer nutrient poor waters. This model has been used to explain the loss of corals in other parts of the globe. However, there have been questions about the d18O records this has been based on and how accurately they reflect SSTs. In this presentation, we show new TEX86 SST data from the Queensland Plateau. Our data shows, instead of cooler SSTs during the Late Miocene, warmer SSTs than the modern Coral Sea and similar temperatures than the West Pacific Warm Pool. In fact, our temperatures fall comfortably in the modern coral growth window. Furthermore, we found little evidence of increases in local nutrients during this time. All this makes it unlikely that cooler SSTs during the Late Miocene caused the loss of corals on the Queensland Plateau. Instead, the changes seem to be linked to more Pacific wide changes during this period of time. Given the modern debate about the future of coral reefs in a warmer world it is critical to understand what changes drive the loss of coral reefs in the past. Our records show that new ideas about coral loss are needed and that better paleoclimate records are needed from these critical environments.
Geopropy: An open source tool to generate 3D geological cross sections 
Authors: Hassanzadeh Ashkan , Vázquez-Suñé Enric , Corbella Mercè , Criollo Rotman
Published: March 2022

Cross sections play a significant role in environmental and geological studies. In general, underground models  can be generated by experienced geologists or derived from mathematical-based geological data interpolation. In this work we present Geopropy, a hybrid knowledge-data driven tool that mimics the straightforward stages that a geologist follows to generate a geological cross-section, taking into account the available data but without using complex mathematical algorithms of interpolation. Geopropy separates the areas with one possible geological outcome from those with multiple possible geological scenarios based on the given hard data. The algorithm creates the cross section in the simple areas and in order to reach a unique outcome, the user is asked for decisions or more hard data in semi-automatic and manual stages based on the complexity of the cross section. The outputs are 3D shapefiles that are again checked  with the introduced hard data to avoid inconsistencies or possible personal biases. Geopropy is therefore an open source Python library support tool for geologists in explicit modelling that aims to reach simple, consistent and fast results.
Creep and acoustic emission in Shales from the Barents Sea
Authors: Sabitova Alina , Stanchits Sergey , Yarushina Viktoriya , Peshkov Georgy , Khakimova Lyudmila , Stukachev Vladimir
Published: March 2022

Nowadays, environmental awareness has become one of the key directions of humankind development. There are a lot of projects aimed at preserving the environment: ensuring the environmental safety of geothermal energy facilities; study of global geodynamics and its influence on the composition, state, and evolution of the biosphere; geoecological substantiation of safe placement, storage, and disposal of toxic, radioactive and other wastes, etc. An essential role is assigned to the storage of increasing volumes of carbon dioxide gas. This problem requires complex approaches and solutions. Given that both CO2 and radioactive storage are long-term projects, it is necessary to investigate the creep process to monitor the state of the underground environment and assess the risks of leakage. A viscous deformation of the formation accompanies the prolonged loading. Viscosity is an essential parameter in coupling fluid flow and deformation processes occurring on Earth [Sabitova et al., 2021]. At the same time, focused fluid flow is a common phenomenon in sedimentary basins worldwide. Flow structures often penetrate the sandy reservoir rocks and clay-rich caprocks [Peshkov et al., 2021]. The impacts of the viscoelastic deformation of clay-rich materials need to be evaluated from an experimental and modeling perspective to understand better the mechanisms forming such structures. Here, we present multistage triaxial laboratory creep experiments with acoustic emission analysis conducted on samples from the Barents Sea. We performed lithological and geochemical characterization of each sample as a petroleum system element. Bulk and shear viscosities used in numerical models are calculated for all samples. The experimental curves are explained using the theoretical model for porous rock viscoelastoplastic (de)compaction [Yarushina et al., 2020].

References:

Sabitova, A., Yarushina, V. M., Stanchits, S., Stukachev, V., Khakimova, L., & Myasnikov, A. (2021). Experimental compaction and dilation of porous rocks during triaxial creep and stress relaxation. Rock Mechanics and Rock Engineering, 54(11), 5781-5805.

Peshkov, G. A., Khakimova, L. A., Grishko, E. V., Wangen, M., & Yarushina, V. M. (2021). Coupled Basin and Hydro-Mechanical Modeling of Gas Chimney Formation: The SW Barents Sea. Energies, 14(19), 6345.

Yarushina, V. M., Podladchikov, Y. Y., & Wang, L. H. (2020). Model for (de) compaction and porosity waves in porous rocks under shear stresses. Journal of Geophysical Research: Solid Earth, 125(8), e2020JB019683.
A spatiotemporal deep learning forecasting model for long-term drought prediction
Authors: Loukas Athanasios , Vasiliades Lampros
Published: March 2022

Droughts are slow-moving natural hazards that comes with high hazardous impacts on the society. Early and timelines forecasting of a drought event can help to take proactive measures and set out drought mitigation strategies to alleviate the impacts of drought. Traditionally, forecasting techniques have used various time-series and/or machine learning methods. However, the use of deep learning methods has not been tested extensively despite its potential to improve our understanding of drought characteristics. This study develops a hybrid spatiotemporal scheme for integrated spatial and temporal forecasting. Temporal forecasting is achieved using a deep feed-forward neural network (DFFN and the temporal forecasts are extended to the spatial dimension using a deep learning approach the Long Short-Term Memory (LSTM) to forecast an operational meteorological drought index the Standardized Precipitation Index (SPI) calculated at multiple timescales. The temporal input variable determination is achieved with the use of the Gamma test that estimates the minimum mean square error (MSE) that can be achieved when modelling the unseen data using any continuous non-linear models. 48 precipitation stations and 18 independent precipitation stations, located at Pinios river basin in Thessaly region, Greece, are used for the development and spatiotemporal validation of the hybrid deep learning forecasting model. Several drought characteristics (drought severity and duration, drought category and spatial extent) are analysed to better understand how drought forecasting was improved. Several quantitative temporal and spatial statistical indices are considered for the performance evaluation of the models. Furthermore, qualitative statistical criteria based on contingency tables between observed and forecasted drought episodes are calculated. The results show that the lead time of forecasting for operational use depends on the SPI timescale. The hybrid spatiotemporal deep learning forecasting model could be operationally used for predicting up to three months ahead for SPI short timescales (e.g. 3-6 months) up to six months ahead for large SPI timescales (e.g. 12-24 months). The above findings could be useful in developing a drought preparedness plan in the region and for drought mitigation purposes.

 

Key words: deep learning, drought, Standardized Precipitation Index, drought forecasting, spatiotemporal droughts, DFNN, LSTM.
Immersive Virtual Reality for Geo-education: feedback from students, academics and the lay public
Authors: Bonali Fabio Luca , Russo Elena , Vitello Fabio , Antoniou Varvara , Tibaldi Alessandro , Fallati Luca , Bracchi Valentina , Savini Alessandra , Whitworth Malcolm , Drymoni Kyriaki , Pasquaré Mariotto Federico , Nomikou Paraskevi , Sciacca ‬‬‬‬‬‬Eva , Bressan Sofia , Falsaperla Susanna , Reitano Danilo , van Wyk de Vries Benjamin , Panieri Giuliana , Stiller-Reeve Mathew Alexander , Becciani Ugo ,   others
Published: March 2022

Field-based classes in geological sciences are crucial components of geoscience education and research. Owing to the COVID-19 pandemic, such activities became problematic due to limitations such as travel restrictions and lockdown periods: this motivated the geoeducational community to tailor new ways to engage people in field activities. As a result, we adopted Immersive Virtual Reality as a tool to involve students, academics, and the lay public in field exploration, thus making geological exploration accessible also to people affected by permanent or temporary motor disabilities. In particular, we evaluated how users perceive the usefulness of this approach as applied to Earth Science learning and teaching, through nine outreach events, where a total of 459 participants were involved, with different ages and cultural backgrounds. The participants explored, in an immersive mode, four geological landscapes, defined as virtual geological environments, which have been reconstructed by cutting-edge, unmanned aerial system-based photogrammetry techniques. They include: Santorini (Greece), the North Volcanic Zone (Iceland), and Mt. Etna (Italy). After the exploration, each participant filled in an anonymous questionnaire. The results show that the majority would be willing to repeat the experience, and, most importantly, the majority of the students and Earth Science academics who took part in the navigation confirmed the usefulness of this technique for geo-education purposes. Our approach can be considered as a groundbreaking tool and an innovative democratic way to access information and experiences, as well as to promote inclusivity and accessibility in geo-education, while reducing travel costs, saving time, and decreasing the carbon footprint. This work has been carried out in the framework of the following projects: i) ACPR15T4_ 00098 “Agreement between the University of Milan Bicocca and the Cometa Consortium for the experimentation of cutting-edge interactive technologies for the improvement of science teaching and dissemination” of Italian Ministry of Education, University and Research (ARGO3D - https://argo3d.unimib.it/); ii) Erasmus+ Key Action 2 2017-1-UK01-KA203- 036719 “3DTeLC – Bringing the 3D-world into the classroom: a new approach to Teaching, Learning and Communicating the science of geohazards in terrestrial and marine environments” (http://3dtelc.lmv.uca.fr/; https://www.3dtelc.com/); iii) 2018 EGU Public Engagement Grants (https://www.egu.eu/outreach/peg/).
Assessing the effect of spatial autocorrelation in predicting groundwater salinity with Machine Learning
Authors: Tziachris Panagiotis , Arampatzis George , Aschonitis Vassilios , Sachsamanoglou Katerina , Tziritis Evangelos
Published: March 2022

Machine learning (ML) models that are robust, efficient and exhibiting sound generalization capabilities rely on the assumption that they are trained with data that are independent and identically distributed (i.i.d). Violating this assumption may result in overfitting these highly flexible methods to the training data and underestimating spatial prediction errors. Making models appear more reliable than they are, could lead in a bias assessment of the model’s capability to generalize the learned relationship to independent data and consequently models with overall poor prediction accuracy.

Spatial data are special kind of data that the i.i.d. does not hold most of the times due to their spatial autocorrelation. Cross-validation is a very common resampling method both for the tuning of ML models and for the assessment of their predictive capabilities. Studies have shown that using random cross-validation methods with spatial data could produce overoptimistic results due to the violation of the i.i.d assumption. In order to mitigate this problem, spatial cross-validation is proposed alternatively that splits the data into spatially disjoint subsets, which are subsequently used for cross-validation.

In the context of the MEDSAL Project (www.medsal.net), multiple data of different covariates were collected in order to study groundwater salinization. Machine learning was applied to predict salinity concentration based on these data. In the current presentation some of the results of the ML analysis are shown along with the effect of the spatial autocorrelation in the ML models' prediction capabilities. This was implemented by comparing the prediction results of the ML models created with random cross-validation versus spatial cross-validation resampling methods. Possible spatial autocorrelation, along with time series autocorrelation, in water data are important issues that data analysts should study and address especially when pairing with ML analysis and modeling.
Intercomparison of air quality models in São Paulo, towards an operational ensemble forecasts system
Authors: Deroubaix Adrien , Hoelzemann Judith , Duarte Edicle , Franke Philipp , Elbern Hendrik , de Fatima Andrade Maria , Lange Anne-Caroline , Martins Leila , Pedruzzi Rizzieri , Toledo Taciana , Von-Marttens Lya , Ynoue Rita Yuri , Brasseur Guy
Published: March 2022

Predicting air quality in megacities is challenging due to the diversity and variability of emission sources, as well as the specific meteorology and photochemistry occurring in the urban boundary layer.

São Paulo is by far the largest city in South America, one of the biggest megacities of the world, located near the coast and on a plateau at about 800 m above sea level, in a tropical climate. A megacity such as São Paulo is therefore a challenge for regional air quality models, which must be used at a resolution high enough to sufficiently accurately represent the processes leading to the high concentrations and high diurnal variability of the main pollutants. On the other hand, the measurement network is composed of 26 stations within the metropolitan area and another 63 within the state of São Paulo mostly in or near other cities, which constitutes an excellent support for evaluating the model outputs.

In this study, we assess the strengths and weaknesses of modeled concentrations of regulated pollutants (CO, O3, NO2, PM2.5, PM10), over three contrasting time periods in 2019. Four Chemistry-Transport models are involved in this intercomparison of high-resolution modeling results, less than 5 km. We study primary pollutants, meteorology, photochemistry as well as the performance of ozone and PM2.5 alerts when WHO air quality standards are not met. The results show that all models have good performance depending on the period and pollutants, and the performance of multi-model median is the best, as has already been shown for other regions.

In the framework of the KLIMAPOLIS project, the perspective of our study is to build an operational air quality forecasting system for the São Paulo region based on ensemble forecasts.
Recent advancements in the evolution of the Black Sea Monitoring and Forecasting Centre
Authors: Peneva Elisaveta , Ciliberti Stefania Angela , Gregoire Marilaure , Staneva Joanna , Palazov Atanas , Coppini Giovanni , Lecci Rita , Matreata Marius , Marinova Veselka , Masina Simona , Pinardi Nadia ,   Black Sea Monitoring and Forecasting Centre
Published: March 2022

In the framework of the Copernicus Marine Service (CMEMS), the Black Sea Monitoring and Forecasting Centre (BS-MFC) is the European reference service for the provision of ocean analyses, forecasts and reanalyses in the Black Sea basin. It ensures a high level of efficiency in terms of operations, science and technology for the Black Sea predictions and monitoring of the physical including waves and biogeochemical processes. This work provides an overview of the BS-MFC modelling systems together with a description of the main operational products delivered through CMEMS interfaces. The product catalogue includes near real time and multi-year datasets, including interim recently introduced in the offer and developed in the perspective of future provisioning of monitoring indicators. The BS Physics unit delivers analysis and forecast products over a domain of about 2.5 km in horizontal with 121 vertical levels, based on NEMO v4.0 online coupled to OceanVar for the assimilation of insitu and satellite observations. It implements open boundary conditions at the Marmara Sea by means of high resolution ocean fields provided by the Unstructured Turkish Straits System. The BS Biogeochemistry unit delivers near real time and multi year products over a domain of about 3 km resolution and 31 levels, based on NEMO v3.6 online coupled to BAMHBI, able to assimilate daily L3 satellite chlorophyll observation by using the Ocean Assimilation Kit developed as part of the SANGOMA project. The BS Waves unit delivers analysis and forecast products over the same domain of BS Physics. The model is based on WAM Cycle 6, forced by surface currents and sea surface height provided by the BS Physics forecasting system. BS-MFC near real time systems are forced by ECMWF IFS analysis and forecast atmospheric fields. BS-MFC multi year systems are instead forced by ECMWF ERA5 reanalysis atmospheric fields and provide past reconstruction of the ocean state in the Black Sea at the resolution of about 3 km horizontally. Since May 2021, interim datasets are also provided with the objective to support marine monitoring capacities in the area. The work focuses on the product quality assessment of relevant BS-MFC variables and on future upgrades for improving the accuracy of forecast and reanalysis.
Extreme sub-centennial Dead Carbon Fraction variability in a predominantly hydroclimate-driven environment
Authors: Gafriller Judith , Therre Steffen , Schorndorf Nils , Warken Sophie F. , Keppler Frank , Friedrich Ronny , Vieten Rolf , Mielke Aaron , Frank Norbert
Published: March 2022

Tremendous progress has been made in the research on mechanisms modulating the dead carbon fraction (DCF) in speleothems, but the causes for high spatial and temporal variability of DCF in different climate zones are still not understood. We have chosen a predominantly hydroclimate-driven environment in the tropics to assess the variability of the DCF and to attempt to reveal the key governing processes. Our high-resolution 14C record obtained from a 230Th/U-dated stalagmite from Larga Cave, Puerto Rico, covers large parts of the last glacial between 41 ka and 12 ka before present (BP), as well as the past 400 years BP in the Holocene. Moreover, hydroclimate variability is resolved through trace metal ratios (e.g. Mg/Ca) and stable oxygen and carbon isotope records (δ18O and δ13C).

The stable isotopes and Mg/Ca time series exhibit a relatively stable mean state indicative of a generally constant hydroclimate (wet vs. dry) and a superimposed correlated variability on the millennial scale. On the contrary, the DCF values are extremely variable on a large range, from 20% to more than 50%. The DCF data indicates that the carbon cycling switches on a sub-centennial time-scale between three apparent modes: a maximum host rock dominated level around 50%, a more soil carbon driven mode around 25%, and an intermediate state in the range of 35%. Notably, this high variability seems to be absent in the Holocene growth period. However, DCF data of another stalagmite from the same cave at a significantly more ventilated location suggest relatively stable DCF values of 15-25 % throughout the glacial period.

With our multi-tracer record from Larga Cave, Puerto Rico, we will discuss the possible dominant processes causing the oscillation between the aforementioned distinct modes of carbon cycling. The comparison to records from the same cave and other locations in the area will disentangle local karst processes and hydroclimate influences on both spatial and temporal scales.