bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of pore space topology on ultrasonic wave propagation in volcanic rocks.
Authors: Di Martino Maria Del Pilar , De Siena Luca , Tisato Nicola
Published: March 2022

At the field scale, petro-elastic models linking seismic velocities with porosity have been widely used to estimate properties of reservoirs and subsurface domains in general. At the laboratory scale, frame elastic properties and porosity are not enough to predict the full ultrasonic wave propagation, and other factors like texture, pore space topology and fluid interactions play a significant role. In dry volcanic rocks characterized by larges vesicles, the heterogeneities triggering the perturbations of the ultrasonic wavefield mainly correspond to the pore space topology. However, the sensitivity of S-waveforms to the pore space has not been examined in volcanic rocks.

To assess the role of the pore space on ultrasonic wave propagation, we performed computational simulations on 2D synthetic samples analogous to volcanic rocks, resembling the acquisition of S-waveforms in laboratory experiments. The computational framework applied is the spectral-element method. The porosity and aspect ratio on the study samples was kept constant along the simulations to focus on the effect that the pore space parameters have on the wave arrival, amplitude, and shape of the waveforms.

This study shows that the pore space topology controls the waveform of ultrasonic waves in dry volcanic rocks, and parameters like amount, size, and even the location of the pores impact the elastic wave propagation independently of the porosity value. This finding has important implications for forward modelling seismic signals of heterogeneous volcanic media at the field scale.
Impacts of atmospheric transport and biomass burning on the inter-annual variation in black carbon aerosols over the Tibetan Plateau
Authors: Han Han , Wu Yue , Liu Jane , Zhao Tianliang , Zhuang Bingliang , Wang Honglei , Li Yichen , Chen Huimin , Zhu Ye , Liu Hongnian , Wang Qin'geng , Li Shu , Wang Tijian , Xie Min , Li Mengmeng
Published: March 2022

Atmospheric black carbon (BC) in the Tibetan Plateau (TP) can largely impact regional and global climate. Applying a backward-trajectory method that combines BC concentrations from a global chemical transport model, GEOS-Chem, and trajectories from the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, we assess the contributions of worldwide source regions to surface BC in the TP. We estimate that on a 20-year average (1995-2014), 77% of surface BC in the TP comes from South Asia (43%) and East Asia (35%). In terms of the amount of BC imported, South Asia and East Asia are dominant source regions in winter and summer, respectively. However, in terms of affected areas in the TP, South Asia is the dominant contributor throughout the year. Inter-annually, surface BC over the TP is largely modulated by atmospheric transport of BC from non-local regions year-round and by biomass burning in South Asia, mostly in spring. We find that the extremely strong biomass burning in South Asia in the spring of 1999 greatly enhanced surface BC concentrations in the TP (31% relative to the climatology). The strength of the Asian monsoon correlates significantly with the inter-annual variation in the amount of BC transported to the TP from non-local regions. In summer, a stronger East Asian summer monsoon and a South Asian summer monsoon tend to, respectively, lead to more BC transport from central China and north-eastern South Asia to the TP. In winter, BC transport from central China is enhanced in years with a strong East Asian winter monsoon or a Siberian High.
A two-stage machine learning framework using global satellite data of cloud classes for process-oriented model evaluation
Authors: Kaps Arndt , Lauer Axel , Camps-Valls Gustau , Gentine Pierre , Gómez-Chova Luis , Eyring Veronika
Published: March 2022

Clouds play a key role in weather and climate but are quite challenging to simulate with global climate models as the relevant physics include non-linear processes on scales covering several orders of magnitude in both the temporal and spatial dimensions. The numerical representation of clouds in global climate models therefore requires a high degree of parameterization, which makes a careful evaluation a prerequisite not only for assessing the skill in reproducing observed climate but also for building confidence in projections of future climate change. Current methods to achieve this usually involve the comparison of multiple large-scale physical properties in the model output to observational data. Here, we introduce a two-stage data-driven machine learning framework for process-oriented evaluation of clouds in climate models based directly on widely known cloud types. The first step relies on CloudSat satellite data to assign cloud labels in line with cloud types defined by the World Meteorological Organization (WMO) to MODIS pixels using deep neural networks. Since the method is supervised and trained on labels provided by CloudSat, the predicted cloud types remain objective and do not require a posteriori labeling. The second step consists of a regression algorithm that predicts fractional cloud types from retrieved cloud physical variables. This step aims to ensure that the method can be used with any data set providing physical variables comparable to MODIS. In particular, we use a Random Forest regression that acts as a transfer model to evaluate the spatially relatively coarse output of climate models and allows the use of varying input features. As a proof of concept, the method is applied to coarse grained ESA Cloud CCI data. The predicted cloud type distributions are physically consistent and show the expected features of the different cloud types. This demonstrates how advanced observational products can be used with this method to obtain cloud type distributions from coarse data, allowing for a process-based evaluation of clouds in climate models.
Unraveling debris-flow erosion: experimentally assessing the effects of debris-flow composition on erosion
Authors: de Haas Tjalling , Roelofs Lonneke , Colucci Pauline
Published: March 2022

Understanding erosion and entrainment of material by debris flows is essential for modelling debris-flow volume growth and prediction of hazard potential. Recent advances have highlighted two driving forces behind debris flow erosion; impact and shear forces. How erosion and these forces depend on debris-flow composition and interact remains unclear. We experimentally investigated the effects of debris-flow composition and volume on erosion processes in a small-scale flume with a loosely packed bed. We quantified the effects of gravel, clay and solid fraction in the debris flow on bed erosion. Erosion increased linearly with gravel fraction and volume, and decreased with increasing solid fraction. Erosion was maximal around a volumetric clay fraction of 0.075 (fraction of the total solid volume). Under varying gravel fractions and flow volumes erosion was positively related to both impact and shear forces, while these forces themselves correlate. Results further show that the internal dynamics driving the debris flows, quantified by Bagnold and Savage numbers, correlate to erosional processes and quantity. Impact forces became increasingly important for bed erosion with increasing grain size. The experiments with varying clay and solid fractions showed that the abundance and viscosity of the interstitial fluid affect debris-flow dynamics, erosional mechanisms and erosion magnitude. High viscosity of the interstitial fluid inhibits the mobility of the debris flow, the movement of the individual grains, the transfer of momentum to the bed by impacts, and therefore inhibits erosion. High solid content possibly decreases the pore pressures in the debris flow and the transport capacity, inhibiting erosion, despite high shear stresses and impact forces. Our results show that bed erosion quantities and mechanisms may vary between debris flows with contrasting composition, and stress that entrainment models and volume-growth predictions may be substantially improved by including compositional effects.
Persistent warm and dry extremes over the Eastern Mediterranean during winter: the role of upstream Rossby wave pattern
Authors: Raveh-Rubin Shira , Berkovic Sigalit
Published: March 2022

Persistent dry winter events over the Eastern Mediterranean (EM) disrupt the precipitation patterns in the rainy (winter) season and dramatically reduce water availability in the region. Self-organizing map classification of atmospheric profile data over Israel has shown that the most persistent (over 4 days) dry and warm winter extreme events are induced by a stagnant ridge over the EM, pronounced trough/cutoff low over the western/central Mediterranean and blocking over the north Atlantic. It is however, unclear how this Rossby wave pattern emerges and what are the atmospheric mechanisms that govern the associated development of dry and warm surface conditions. Here we objectively identify persistent dry and warm winter events over Israel, and focus on three case studies, aiming to understand the relation between the baroclinic synoptic setting, precursor Rossby waves, and how the dry and warm conditions emerge using a Lagrangian approach to study the history of the involved airmasses. We found large day-to-day variability within events and identified the leading mechanisms of the warm and dry conditions to be: adiabatic heating during slantwise subsidence, heating by sensible heat fluxes from the surface, and advection of warm and dry continental air. In addition, the Atlantic blocking and EM ridge are supported by upstream diabatic heating in warm conveyor belts (WCB) of north Atlantic cyclones and Mediterranean cyclones, respectively. A tripole flow during these events demonstrates the sequential relation between Atlantic ridge (or block), trough over Europe and ridge over EM and/or West Russia. These results place local persistent warm and dry anomalies as an outcome of a stationary Rossby-wave pattern, providing new opportunities for understanding such extremes and their predictability.
Self-organizing map classification of the boundary layer profile – a refinement of Eastern Mediterranean winter synoptic regimes
Authors: Berkovic Sigalit , Mendelsohn Oz Yosef , Ilotoviz Eyal , Raveh-Rubin Shira
Published: March 2022

The boundary layer (BL) profile over the coastal plain of Israel, Eastern Mediterranean (EM),
varies considerably during winter. Although, in the context of air pollution, the
characteristics of the BL height (BLH) was intensively investigated, a quantitative
classification of the BL profile regimes has not been performed. Here, we seek to reveal the
dominant, recurring regimes of the BL profiles, their quantitative characteristics and links to
regional synoptic-scale patterns.
An objective unsupervised classification of winter BL radiosonde profiles is performed for
the first time by multi-parameter self-organizing map (SOM) analysis. The analysis uses high-
resolution, 12-UTC data of wind, temperature, humidity and pressure measurements during
Dec-Feb 2007-2018, and yields 30 distinct profile regimes.
Composite analysis using ERA5 reanalysis suggests strong association between the profile
regimes and synoptic weather systems and highlights four groups: 1. Deep winter cyclones
with strong westerly wind and precipitation; 2. Strong surface anticyclones and Red Sea
troughs (RST) with a mid-tropospheric ridge, moderate dry easterly wind and extreme
temperatures. 3. Moderate pressure gradients under shallow cyclones, anticyclone to the
west and RST to the east of Israel. 4. Active RSTs, accompanied by upper-tropospheric
trough/cutoff low and heavy precipitation. For the first time, general objective classification
observes the active RST without requiring specific criteria.
Consistent with previous knowledge, the new classification exhibits distinct categories of
thermal stability, BLH and turbulence. Importantly, we show that the automatic objective
classification of profile data from a single station can be a sensitive discriminator of winter
synoptic regimes in the EM, and therefore explains the variability of the BL profile. It
facilitates the study of the interaction between the BL and the free troposphere and may
improve the prediction of air pollution or future BL profile regimes based on long time series
from historical data or climate models.
The mistral wind from a Rossby-wave perspective: a climatological classification of RWB
Authors: Givon Yonatan , Keller Jr. Douglas , Silverman Vered , Pennel Romain , Drobinski Philippe , Raveh-Rubin Shira
Published: March 2022

The Gulf of Genoa is one of the most cyclogenetic places on the globe, mostly due to Alpine lee-cyclogenesis. The mistral wind is an inherent feature in this process, known for its positive contribution to the deepening of the lee-cyclone. The mistral is recognized by many as one of the most dangerous weather regimes in the Mediterranean and has been associated to extreme weather events in the region. While extensive research has focused on the lower-tropospheric mistral and lee cyclogenesis, the features of the Rossby waves that drive the process are not generally known. Here, the isentropic potential vorticity (PV) structures governing the occurrence of the mistral wind are classified using a self-organizing map (SOM) clustering algorithm. A 36-year (1981–2016) climatological classification of Rossby waves generating a mistral wind is performed based on daily ERA-Interim isentropic PV data. 16 distinct mistral associated PV structures are identified, where each classified flow pattern corresponds to a different type or stage of the Rossby wave life cycle. From broad troughs to thin PV streamers to distinguished cutoffs, each of these PV patterns exhibits a distinct surface impact. A clear seasonal separation between the clusters is evident, and transitions between the clusters correspond to different Rossby wave- breaking processes. This analysis provides a new perspective on the surface impact of Rossby waves throughout their lifetimes, and their influence on extreme weather events. 
Energy flux quantification in the oceanic internal wavefield
Authors: Dematteis Giovanni , Polzin Kurt , Lvov Yuri
Published: March 2022

The rate of diapycnal mixing, largely due to internal-wave breaking, is a key ingredient to understanding upwelling and horizontal circulation in the ocean. Here, we show a first-principles quantification of the downscale energy flux in the internal wavefield, that ultimately feeds the wave-breaking, shear-instability energy sink responsible for mixing. The approach is based on the wave kinetic equation that describes the inter-scale energy transfers via 3-wave nonlinear resonant interactions. Our results compare favorably with the phenomenological ‘Finescale Parameterization’ formula, by which deep ocean mixing is commonly implemented in the global models, and provide novel insights in the complex problem of oceanic energy transfers.
Biogels in the rhizosphere: Plant mucilage as a biofilm matrix that shapes the rhizosphere microbial habitat
Authors: Nazari Meisam , Bickel Samuel , Benard Pascal , Mason-Jones Kyle , Carminati Andrea , Dippold Michaela Anna
Published: March 2022

Mucilage is a gelatinous high-molecular-weight substance produced by almost all plants, serving numerous functions for plants and soil. To date, research has mainly focused on the hydraulic and physical functions of mucilage in the rhizosphere. Studies on the relevance of mucilage as a microbial habitat are scarce. Microbial research has largely focused on extracellular polymeric substances (EPS), gelatinous high-molecular-weight substances produced by microorganisms. In soil, EPS support the establishment of microbial assemblages by providing a moist environment, a protective barrier, and serving as carbon and nutrient sources. Our analyses show that mucilage shares the physical and chemical properties of EPS. Mucilage covers large extents of the rhizosphere and could function similarly to the biofilm matrix. Our laboratory and theoretical analyses largely confirmed similar viscosity and surface tension as important physical properties and polysaccharide, protein, neutral monosaccharide, and uronic acid composition as major chemical properties. Our study suggests that mucilage provides functions of EPS required for biofilm formation. Mucilage offers a protected habitat optimized for nutrient mobilization and provides carbon and nutrients. We suggest that the function of mucilage as a biofilm matrix and enabler of high rhizo-microbial abundance and activity has been strongly underestimated, and should be considered as an essential component of conceptual models of the rhizosphere. 
Exploring Comet 67P through art and science
Authors: Smirnova Ekaterina
Published: March 2022

In November 2014 the Rosetta mission by the European Space Agency (ESA) sent a spacecraft to comet 67P/Churyumov–Gerasimenko. The data published from the mission inspired me as an artist to create a set of artwork about 67P, including paintings, sculptures and musical collaborations. During this seven-year-long project, I collaborated with scientists from ESA and NASA. Acting as an interpreter from science to non-scientists I implement scientific data into my artwork. Allowing my work to be interactive via Augmented Reality (AR) I invite my viewers to study about the Rosetta mission via art. 

For the return of the comet in 2021 I have created two new paintings. This time I am starting a conversation about the origins of life on Earth, suggesting that comets perhaps played a big role. Colonies of bacteria grown in my art lab have become a part of my paintings.

During the EGU conference in 2022, I would like to display a series of large watermedia paintings. All of the paintings were created with special water that I generated to be close in composition to the water on the comet. 

Work sizes: 70”x52”; 90”x258” (largest piece, if the space allows).

A few of the works could be experienced with AR, instruction to which will be provided to viewers. AR is inspired by the spectroscopic data of an instrument onboard the spacecraft Rosetta. An image with a sound will be visible for viewers via their smart devices. 

If space allows, a music video could be displayed during the exhibition. This video was a collaboration project between myself, a clarinetist from Wales, a composer from Japan and a film editor from New York. This piece is inspired by the sonification of the magnetometry readings of the comet. 

A poster and a public talk can also be provided.
The Adriatic Sea and Coast (AdriSC) modelling suite: coupled atmosphere-ocean kilometer-scale assessments of present and future climates
Authors: Vilibić Ivica , Denamiel Clea , Tojčić Iva , Pranić Petra
Published: March 2022

We present a variety of applications of the climate component of the coupled atmosphere-ocean kilometer-scale Adriatic Sea and Coast (AdriSC) modelling suite.  The AdriSC modelling suite has been implemented to represent both atmospheric and oceanic dynamics in the Adriatic Sea region and, in particular, to reproduce processes at the mesoscale (i.e. at the kilometer-scale or higher resolutions) like meteotsunamis (atmospherically-generated long-ocean waves in the tsunami frequency band) or orographically-driven winds. For that reason, two different modules have been developed conjointly in the AdriSC model. First, the basic module provides the kilometer-scale atmospheric and oceanic Adriatic baroclinic circulation with the Weather Research and Forecast (WRF) model at up to 3 km resolution in the atmosphere and the Regional Ocean Modelling System (ROMS) in the ocean, coupled with the Simulating WAves Nearshore (SWAN) model for surface waves at up to 1 km resolution. Second, the dedicated nearshore module is used to better reproduce atmospherically driven extreme sea level events, and couples offline the WRF 1.5 km grid in the atmosphere with the ADCIRC-SWAN unstructured mesh down to 10 m resolution along the Adriatic coastline.

Two different approaches – based on Pseudo-Global Warming (PGW) methodology – have been implemented to assess the impact of climate change in the Adriatic Sea: (1) short-term event-oriented simulations to represent the dynamics of extreme events with the nearshore module, and (2) long-term simulations (31-years), based solely on the basic module, to derive statistics of present (1987-2017) and future (2070-2100) climates. More precisely, the numerically unexpansive short-term simulations were used (1) to verify the implementation of the PGW methodology in the ocean and (2) to derive the impact of climate change on the bora wind dynamics and the associated wintertime cooling in the northern Adriatic Sea, as well as on the surface wave dynamics generated by dominant winds (sirocco, bora) and meteotsunamis. Concerning the expansive 31-year long simulations, they each took 18 months of run on the European Centre for Middle-range Weather Forecast (ECMWF) supercomputer to provide, for the very first time, a reliable kilometer-scale coupled atmosphere-ocean dataset – fully evaluated against observations in both atmosphere and ocean. Consequently, kilometer-scale coastal hazards under extreme climate changes can now be fully assessed by researchers, but also environmental agencies in the Adriatic region.

The research was supported by the Croatian Science Foundation (projects BivACME and ADIOS).
The contribution of Satellite-data driven snow routine to karst hydrological models
Authors: Calli Suleyman Selim , Özdemir Calli Kübra , Yılmaz M. Tuğrul , Çelik Mehmet
Published: March 2022

Snow recharge is an important dominant hydrological process in the high altitude mountainous karstic aquifer systems. In general, widely used karst hydrological models (e.g., KarstMod, Varkarst) do not include a snow routine in the model structure to avoid increasing the number of model parameters while representing the complex hydrological process. As a result, recharge process is not represented well, which questions the optimality of the results that can be obtained under available datasets. This study presents a novel pre-processing method –called SCA routine– to compensate for the missing snow routine in karst models. The proposed pre-processing method is driven by the temperature, precipitation, and satellite-based snow observation datasets while classifying the precipitation input into three physical phases (rain, snow, and mixed) based on the temperature datasets to distribute each phase over the catchment using satellite-driven Snow-Covered Area (SCA) products. By the proposed method, the spring discharge simulation result is regulated well in time and magnitude. To examine the added utility of the SCA routine, the SCA-included simulation results are compared to the model performances with no routine and the classical Degree-Day method as a benchmark. To test the efficiency of our proposed method we use a karst hydrological model (KarstMod) to simulate the karst spring discharge in a well-observed semi-arid snow-dominated karstic aquifer (Central Taurus, Turkey). Our results confirm that the KarstMod model coupled by SCA routine ensures better model performance with a value of NSE = 0.784 than those of the classical Degree-day method (NSE = 0.760) and the model with no routine (NSE = 0.306) while providing a physically more realistic parameter set.

Key Words: MODIS, Degree-Day, Hydrological model, Snowmelt, Mountainous karst

 
Promoting and supporting field-based geomorphologists during pregnancy and early motherhood
Authors: Lininger Katherine , Rowan Ann V. , Livers Bridget , Kramer Natalie , Ruiz-Villanueva Virginia , Sendrowski Alicia , Burrough Sallie
Published: March 2022

Many geomorphologists who are mothers find it challenging to balance field research alongside pregnancy and early motherhood. The barriers presented by carrying out fieldwork during pregnancy or as a mother of preschool-aged children can adversely affect the career progress of women and Early Career Scientists at a point that is critical for their retention in scientific research. We offer perspectives on the challenges of fieldwork as mothers and discuss possible solutions that have worked (or not) for us, as a means of promoting conversations and highlighting issues that are less commonly considered in field-based geomorphological research. Although every mother’s experience and needs are different, we discuss strategies for conducting fieldwork, addressing childcare issues, maintaining a research career through this life stage, and dealing with financial considerations such as additional childcare costs. We highlight funders that support mothers in carrying out fieldwork and the problem of institutional restrictions on such spending. We call for our community to support geomorphologists who are pregnant or caring for young children in carrying out fieldwork to help enhance the diversity of voices and perspectives within our discipline. 
Forward modelling of the completeness and preservation of Quaternary palaeoclimate signals recorded by ice-marginal moraines
Authors: Rowan Ann V. , Egholm David Lundbek , Clark Chris D.
Published: March 2022

Glaciers and ice sheets fluctuate in response to climatic change and often record these changes by building ice-marginal (terminal and lateral) moraines. Therefore, glacial landscapes are a potentially valuable archive of terrestrial palaeoclimate change. Typically, a cooling climate causes glaciers to expand and warming causes glaciers to shrink. However, the influence of high-relief mountainous topography on glacier dynamics complicates this behaviour, such that ice-marginal moraines are not always a straightforward palaeoclimate indicator. We used a higher-order ice-flow model to simulate change in glacier erosion, extent, and thickness in the response to climatic change and the resulting formation and preservation of moraines in a synthetic mountain landscape. Our results show that the rate of palaeoclimatic change relative to the glacier’s response time determines the geometry, number and position of ice-marginal moraines. However, glaciers can build distinct moraines in the absence of climate change, and the distance from the glacial maximum may not represent the chronological order of moraine formation. While moraines can be preserved despite erosion during subsequent glaciations, moraine sequences frequently contain gaps that could be misinterpreted as representing more stable palaeoclimates. These results provide theoretical understanding for the interpretation of glacial landforms both in the field and from satellite data (e.g. digital terrain models) to understand Quaternary climate change.
Sea-level modelling in the Mediterranean Sea using data assimilation
Authors: Ferrarin Christian , Bajo Marco , Umgiesser Georg
Published: March 2022

The correct reproduction of sea-level dynamics is crucial for forecasting floods and managing the associated risk. On the other hand, sea-level monitoring through observations can provide a description only of past events and it is challenging and costly, both of time and money. In this context, oceanographic models are increasingly used to describe the sea dynamics, providing a spatial/temporal extension to the observations. The best solution, which merges the observation accuracy and the model spatial/temporal resolution, is the data assimilation analysis, which is particularly important in coastal regions with scarce monitoring resources. In this study, we investigate the benefits of assimilating sparse observations from tide gauges in an unstructured hydrodynamic model for simulating the sea level in the Mediterranean Sea. We use the Ensemble Kalman filter, both to obtain an analysis of the past and to produce accurate forecasts. In the analysis we tested the assimilation in storm-surge simulations, only-tide simulations, and total-level simulations, using the observations in the stations. The results of storm-surge simulations were compared with those of total-level simulations, by adding the tide obtained from harmonic analysis of the observations. RMSE and correlation show improvements for all the components of the sea level and all the stations considered (not assimilated). The averaged-over-station RMSE reduces from 9.1 to 3.4 cm for the total level. The greatest improvements happen when the model without assimilation, due to an error of the wind-pressure forcing, did not reproduce some barotropic free modes of oscillation triggered by an initial surge. The preliminary forecast simulations of storm surge show improvements due to the data assimilation extending up to 5 days of forecasting. Even in this case, the longer improvements seem to happen when a free mode of oscillation is triggered. The results of this study will be used to improve the sea level forecasting system in the Adriatic Sea, developed within the framework of the Interreg Italy-Croatia STREAM project (Strategic development of flood management, project ID 10249186).
The pullout mechanical properties of shrub root systems in a typical karst area, Southwest China
Authors: Ruan Shihang
Published: March 2022

Abstract: Roots play a major role in reinforcing and stabilizing soil. The pullout mechanical characteristics of soil reinforcement and slope protection of the root systems of dominant shrub species (Pyracantha and Geranium) were estimated by in situ pullout tests in a karst area, in which roots were pulled out from soil to reliably test the pulling force. The F-s curves were multipeak curves with a noticeable main peak and main double peaks. The curves showed a linear increasing trend at the initial stage of drawing and decreased rapidly after reaching the peak. The F-s curves of root systems inserted into rock cracks showed secondary fluctuations in the later stage of drawing, and rock cracks stimulated the tensile efficiency of the root system more effectively. The maximum pulling force had a linear relationship with the increase in soil thickness and a disproportionate increasing trend with the increasing number of broken roots. The displacement of the maximum peak was different between the two tree species and was concentrated at 5-15 cm and 5-25 cm for Pyracantha and Geranium, respectively. The maximum pulling force of Geranium was 1.29 times that of Pyracantha, and the root system of Geranium had strong pullout resistance. These findings can enrich the theoretical knowledge of vegetation slope protection and provide a reference for the selection of soil and water conservation tree species.
Hydro-pedotransfer functions: A roadmap for future development       
Authors: Weber Tobias Karl David ,   ISMC Working Group: Pedotransfer functions
Published: March 2022

Hydro-pedotransfer functions (hyPTF) are used to relate available knowledge about soil properties to soil hydraulic properties and parameters of interest for applications in process models. At least more than four decades have been invested to derive such relationships. However, while models, methods, data storage capacity, and computational efficiency have advanced, there are fundamental issues related to the scope and adequacy of current hyPTFs, particularly when applied to parameterise models at the field scale and beyond. Much of the hyPTF development process has focussed on refining and advancing the methods, while fundamental questions remain largely unanswered, namely i) how should hyPTFs be built (methods) for maximum prediction confidence, ii) which processes/properties need to be predicted to move beyond the van Genuchten-Mualem based parameterisation of the Richards equation, iii) which new datasets and data coverage are needed, iv) how does the measurement process of soil hydraulic properties determine the construction of hyPTFs and at which scale, iv) what is the implication of diverging scales (lab measurements/field to regional scale of application), v) what scaling/modulation/constraining strategies are required to make hyPTF predictions at field-to-regional scale appropriate and physically meaningful, and vi) what is the spatial representativeness? These questions have been addressed in a joint effort by the members of the International Soil Modelling Consortium (ISMC) Pedotransfer Functions Working Group with the aim to systematise hyPTF research and provide a roadmap guiding both scientists and reviewers.
Risks of environmental and climate change for the Mediterranean ecosystems, with a focus on mediterranean vines
Authors: Guiot Joel
Published: March 2022

The Mediterranean Basin (which includes the Mediterranean Sea and the countries bordering it) is often referred to as a hotspot for climate change and biodiversity. This image is used to illustrate the multiple risks for the region, its people and its ecosystems. These risks have been assessed by a new analysis of the scientific literature (MedECC 2020), concluding that it is the sum of climate change, pollution, unsustainable use of land and sea and the invasion of non-native species that induces these multiple risks, which are often underestimated. The Mediterranean territory is also a biodiversity hotspot with 25,000 plant species, 60% of which are endemic. It provided a “service” to plant and animal species as refuges during the last ice age (when the climate was much colder and the sea level was 120 m lower). These ecosystems are now under the triple threat of drought, rising sea level and intensified land use. Forest fires due to heat waves and droughts will be increasingly dramatic despite prevention efforts and fire response forces. Climate change, pollution and over-fishing are having a heavy impact on marine ecosystems, which contain 18% of known species and cover 0.82% of the global ocean. This talk will depict a picture of these present and future risks. A focus will be done on the viticulture which is iconic of the Mediterranean agricultural production and which is very vulnerable to climate change especially on its southern fringe where more intense and frequent droughts are projected. The methodology involves the use of a vegetation model offline coupled to earth system models. A shift of several degrees toward the north is projected for the vine area in case of a global warming larger than +2°C according to the pre-industrial period.

MedECC (2020) Climate and Environmental Change in the Mediterranean Basin – Current situation and Risks for the Future. First Mediterranean Assessment Report [Cramer, W., Guiot, J., Marini, K. (eds.)], Union for the Mediterranean, Plan Bleu, UNEP/MAP, Marseille, France, 632pp.
Updated inverse estimation of systematic errors in Earth radiation data from spaceborne accelerometery
Authors: Vielberg Kristin , Kusche Jürgen
Published: March 2022

For low Earth orbit satellites, the atmospheric drag is the largest non-gravitational force. With increasing satellite altitude, the acceleration due to the Earth radiation pressure (ERP) decreases, whereas the effect of the Solar radiation pressure (SRP) becomes prevalent. Models of these non-gravitational forces are applied in satellite gravimetry, thermospheric density estimation, and in the precise orbit estimation.

Here, we present an update of our previous study, where we found that estimating systematic errors in radiation pressure force models appears possible based on an inverse procedure using GRACE data. Our final aim is to calibrate Earth radiation data sets that are used in radiation pressure force models. In a first step, we further improve our precise non-gravitational force models by including thermal radiation pressure with heat conduction. In this context, we also identified and overcame inconsistencies in the emission coefficient of the GRACE macro-model. Then, we systematically search for a suitable parametrization that must involve constraints to overcome multicollinearity between parameters such as errors in the radiation data and in the thermo-optical material coefficients. We apply the inverse modeling using calibrated accelerometry data from the GRACE mission. Since the aerodynamic acceleration is smaller than the solar radiation pressure acceleration during low solar activity, we chose data from 2008 to keep errors due to the aerodynamic modeling to a minimum. The resulting estimates are expected to improve the estimation of certain physical radiation pressure model parameters.
Interannual variability of the 12-hour tide in the mesosphere and lower thermosphere in 15 years of meteor-radar observations above Rothera (68o S, 68o W)
Authors: Dempsey Shaun M , Noble Phoebe E , Wright Corwin J , Moffat-Griffin Tracy , Mitchell Nicholas J
Published: March 2022

The wind field in the mesosphere and lower thermosphere (MLT), at heights between 80 and 100 km, is dominated by the global scale oscillations of the atmospheric tides. The tides are crucial to the dynamics of the middle and upper atmosphere and hence to understanding the coupling between the lower atmosphere and space. The tides are known to show considerable variability on timescales of days to years, with significant variability at interannual timescales.  However, the nature and causes of this variability remain poorly understood. Here, we present measurements made over the interval 2005 to 2020 of the interannual variability of the 12-hour tide as measured at heights of 80 – 100 km by a meteor radar over the British Antarctic Survey base at Rothera (68°S, 68°W). We use a linear regression analysis to investigate correlations between the 12-hour tidal amplitudes and several climate indices, specifically the solar cycle (as measured by F10.7 solar flux), El Niño Southern Oscillation (ENSO), the Quasi-Biennial Oscillation (QBO) at 10 hPa and 30 hPa, the Southern Annular Mode (SAM) and time. Our observations reveal that the 12-hour tide has a large amplitude and a clearly defined seasonal cycle with monthly mean values as large as 35 ms-1. We observe substantial interannual variability with monthly mean tidal amplitudes at 95 km exhibiting an interdecile range in spring of 17.2 ms-1, 12.6 ms-1 in summer, 23.6 ms-1 in autumn and 9.0 ms-1 in winter. We find that F10.7, QBO10, QBO30, SAM and time all have significant correlations at the 95% level, whereas we detect very minimal correlation with ENSO. For example, there is a significant negative correlation between F10.7 solar flux and tidal amplitudes in summer, implying an increase in solar flux is related to a decrease in monthly mean tidal amplitudes in the MLT. These results suggest that the amplitude of the polar 12-hour tide is modulated by the solar cycle, QBO and SAM.
Brucite, a natural raw material used worldwide, can be contaminated by asbestos
Authors: Scognamiglio Valentina , Malferrari Daniele , Di Giuseppe Dario , Gualtieri Alessandro
Published: March 2022

Brucite is a hydroxide mineral [Mg(OH)2] with a hexagonal structure (space group P3m1) consisting of sheets of Mg-centered octahedra. Brucite is a raw material of commercial importance used for several applications, such as flame retardant and smoke suppression product for insulating materials and coatings, inorganic additive in ceramic inks, pigments and cements, for CO2 sequestration and as MgO source. Brucite is a widespread mineral frequently found in marble as a product of alteration of periclase, or as an accessory mineral in metamorphic limestones and dolomite schists, but more commonly brucite crystalizes during the serpentinization of ultramafic rocks. Given the possible concomitant occurrence of naturally occurring asbestos (NOA) in serpentinites, the presence of brucite in these rocks should arise concern. The most common asbestos type in serpentinites is chrysotile, which is classified by the International Agency for Research on Cancer (IARC) as a human carcinogen. North America, North Europe and China are the largest producers and exporters of this raw material, but no particular precautions are taken as it is considered a safe product. To date, the occurrence of chrysotile in commercial brucite had never been reported. Our study demonstrates that this view must be reconsidered. Through multi-analytic protocol based on morphometric, chemical and mineralogical analyses, we highlighted the evidence of respirable regulated chrysotile (serpentine asbestos) fibers in a commercial brucite currently traded worldwide. The presence of a serpentine phase was evidenced by chemical analyses, X-ray powder diffraction and thermogravimetric-thermodifferential analyses while the occurrence of breathable regulated fibers was confirmed by morphometric observations through scanning electron microscopy. Especially, fibers with length >5 µm, width <3 µm, length/width ratio >3, in a concentration of 169 mg/kg (0.02 wt%) were found. In the light of these findings, we think that brucite-exposed workers should be aware of the potential hazard associated with the use of raw brucite. Therefore, we suggest that an asbestos-free certification should be imposed to the brucite mining companies and distributors, through the implementation of a multidisciplinary protocol or at least by electron microscopy, to rule out the occurrence of asbestos. Similar future studies may affect ‘doubtful’ raw materials commonly marketed, such as diopside, olivine and magnesite.
The summer 2021 Switzerland hailstorms: major impacts and unique observational data
Authors: Kopp Jérôme , Schröer Katharina , Schwierz Cornelia , Hering Alessandro , Germann Urs , Martius Olivia
Published: March 2022

From June 18 to July 31, 2021, a series of exceptional hailstorms occurred over Switzerland, causing major damages to buildings, cars, and crop fields. The available estimates from the insurance companies suggest that these events will be among the most expensive of the last decades. At the same time the events provide a unique research opportunity as the hailstorms were well captured by various observing systems: a newly set-up network of automatic hail sensors that report the size and kinetic energy of individual hail stones with very high temporal and size resolution, the crowdsourcing function of the MeteoSwiss app, and two radar-based operational hail products. The recently established radar-based Swiss hail climatology shows that the events of 2021 were extreme with high return periods both in terms of the reported hail stone sizes and in their spatial extent. Using the data captured by those complementary hail-dedicated observing systems, we review the hail activity in Switzerland during the period of interest and investigate two particularly intense hail days: June 28 (HD1) and July 8 (HD2). On HD1, the storms originated in western Switzerland, moved along the northern flank of the Swiss Alps in a Southwest to Northeast motion, and one storm evolved in a mesoscale convective system. On HD2, the storms originated in Northern Italy and moved over Southern Switzerland (Ticino) in a South to North motion. We look at the synoptic-scale situation, mesoscale environment, and storm tracks of HD1 and HD2 in details and demonstrate their exceptional character with respect to the climatology. We touch upon the new research avenues opened by the automatic hail sensors measurements both individually, as they allow to capture the time evolution of the hail stones size distribution, and in combination with the crowdsourcing and radar data (cross-validation of the radar-based hail algorithms).
Machine Learning and Underground Geomechanics – data needs, algorithm development, uncertainty, and engineering verification
Authors: Morgenroth Josephine , Khan Usman T. , Perras Matthew A.
Published: March 2022

Machine learning algorithms (MLAs) are emerging as a powerful tool for forecasting complex and nuanced rock mass behaviour, particularly when large, multivariate datasets are available. In engineering practice, it is often difficult for geomechanical professionals to investigate all available data in detail, and simplifications are necessary to streamline the engineering design process. An MLA is capable of processing large volumes of data quickly and may uncover relationships that are not immediately evident when manually processing data. This research compares two algorithms developed for two mines representing end member behaviours of rock failure mechanisms: squeezing ground with high radial convergence, and spalling ground with high in situ stresses and seismicity. For the squeezing ground case study, a Convolutional Neural Network is used to forecast the yield of the tunnel liner elements using tunnel mapping images as the input. For the high stress case study, a Long Short Term Memory network is used to forecast the in-situ stresses that takes time series microseismic events and geomechanical properties as inputs. The two case studies are used to compare input data requirements and pre-processing techniques. Ensemble modelling techniques used to quantify MLA uncertainty for both case studies are presented. The development of the two MLAs is discussed in terms of their complexity, generalizability, performance evaluation, verification, and practical applications to underground rock engineering. Finally, best practices for MLA development are proposed based on the two case studies to ensure model interpretability and use in engineering applications.
Protects and heats
Authors: walter tavecchio
Published: March 2022

Author: Eurogeologist Walter Tavecchio, CNG Rome, IT

EurGeol number: 1688, Crowd thermal linked third parties

Title: PROTECTS AND HEATS

Abstract

The project combines the building heating / cooling technique with a geotechnical system for attenuating the vibrations induced in the structures by seismic phenomena.

It aims to protect buildings and structures from earthquakes and at the same time provide low enthalpy geothermal energy.

It is applied to the outside of any building: residential, commercial, industrial or sensitive, such as hospitals, theaters, museums, shopping centers, cinemas, supermarkets, skyscrapers, churches, towers, bell towers in urban or archaeological or monumental areas but also in the vicinity of bridges, viaducts and tunnels.

  This system attenuates the vibrations of earthquakes on surface soils and existing structures and produces low-cost geothermal energy by exploiting the perforations already made for the attenuation of vibrations.