bluuebunny/crossref_metadata_2025 huggingface dataset:
Insights from the first analysis of Antarctic water stable isotope simulations for the historical period
Authors: Goursaud Oger Sentia , Sime Louise , Holloway Max
Published: March 2022

The historical period  (from 1850 to present) yields a window when ice core  and good historical data are both available. It thus represents an important period over which to test the relationship between ice core measurements, here stable water isotopes, and Antarctic climate.  Water stable isotopes from ice cores from Antarctica have traditionally been used to infer past surface air temperatures. Here we run an ensemble over the period 1850-2004 using the UK Met Office HadCM3 general circulation model equipped with water stable isotopes.  Simulations of water stable istopes from general circulation model can help in the interpretation of Antarctic ice cores.  This ensemble captures observed temperature and precipitation trends. Interestingly however the water isotopes exhibit little trend. This appears to be explained by compensating effect of two modes of atmospheric dynamics throughout the period. Further we use these results to examine the relationships used in Last Millienium reconstructions based on Antarctic stable water isotopes data from ice cores.  
Applying locally calculated partition coefficients for radiogenic heat sources and volatiles to interior evolution models of terrestrial planets
Authors: Schmidt Julia Marleen , Noack Lena
Published: March 2022

The radiogenic elements K, Th, and U are large contributors to the heating inside a terrestrial planet. Because they act incompatible in solid mantle rocks, they prefer to gather in partial melt, which is generally less dense than the surrounding material and rises upwards. While rising, the melt transports the radiogenic heat sources and other incompatible elements towards the surface, where over time they accumulate inside the crust. The amount of the transported incompatible elements is heavily dependent on their degree of incompatibility in mantle rocks and therefore their mineral/melt partition coefficients. Despite the fact that partition coefficients can change by multiple orders of magnitudes from 0-15 GPa along a peridotite solidus (Schmidt and Noack, 2021), they were generally taken as constant in mantle evolution models due to a lack of high-pressure models and experimental data.

Based on the thermodynamic approach of Blundy et al. (1995), Schmidt and Noack (2021) modelled partition coefficients for sodium in clinopyroxene/melt from 0-15 GPa. As sodium has a very low strain in the M2 lattice site of clinopyroxene and is therefore very compatible, its partition coefficients can act as a reference to model the other elements from. In this study, we take the approach of Schmidt and Noack (2021) to model the partition coefficients of the above-mentioned heat producing elements and volatiles at local P-T conditions for partial melting events inside the mantle of terrestrial planets. We insert local bulk partition coefficients for an adequate mantle rock composition into a 1D interior evolution model of Mars. By comparing the results of the redistribution to models with constant partition coefficients, we can assess the impact of the locally calculated partition coefficients on the accuracy of models which deal with the thermal evolution of a planet and the enrichment of heat producing elements and volatiles inside the crust.

Blundy, J. et al. (1995): Sodium partitioning between clinopyroxene and silicate melts, J. Geophys. Res., 100, 15501-15515.

Schmidt, J.M. and Noack, L. (2021): Clinopyroxene/Melt Partitioning: Models for Higher Upper Mantle Pressures Applied to Sodium and Potassium, SysMea, vol 13 nr 3&4, to be published.
Investigation of the evolution of energy conversion processes at an EDR-accompanied dipolarization front, using polynomial magnetic field reconstruction techniques
Authors: Hosner Martin , Nakamura Rumi , Schmid Daniel , Nakamura Takuma , Panov Evgeny , Korovinskiy Daniil
Published: March 2022

The Dipolarization Front (DF), which is a sharp increase of the northward magnetic field component, accompanied by fast earthward-moving plasma flows, is a well known phenomenon in the Earth's Magnetotail. Plasma characteristics also change at the front, from colder and denser ahead of the front to a hotter and more diluted plasma at the trailing side. The DF is therefore considered to be the boundary between ambient plasma and the hotter reconnection outflow jets. The DF can be the host of several energy conversion processes between plasma particles and waves e.g. due to various instabilities. A recent statistical study by Hosner et al. PoP 2022 showed that all of the studied DFs are accompanied by enhanced wave activity around the lower hybrid frequency, suggesting the high occurrence of the Lower-Hybrid Drift instability (LHDI) at DFs. In the present study we investigate the evolution of the energy conversion process in a flux rope type DF, for which an electron-diffusion region was reported (Marshall et al. JGR 2020). We first examine the wave characteristics and LHDI signatures to compare and to contrast flux rope and non-flux rope type DFs. Secondly, we apply a magnetic field reconstruction technique (Denton et al. JGR 2020) to this event using MMS data, to reconstruct the changes of the local magnetic field structures of the flux rope and temporal/spatial evolution of the energy conversion processes within the DF.
Dynamics of ascending smoke-charged anticyclones
Authors: Podglajen Aurélien , Legras Bernard , Lapeyre Guillaume , Plougonven Riwal
Published: March 2022

Anticyclonically-trapped plumes were discovered following the unprecedented 2020 Australian fires, which saw the rise of a 1,000-km diameter, 6-km deep bubble of tropospheric air enriched in combustion products from 19 to 35 km asl over 3 months. Since then, a number of previous occurrences has been reported, notably in the aftermath of the 2017 Canadian fires. Lifted by solar heating from black carbon aerosols, the long-lived anticyclonic plumes are characterized by a joint upward motion of plume material and anticyclonic potential vorticity (PV).  These newly discovered objects raise fundamental questions from a dynamical standpoint. In particular, although the similar evolution of tracers and PV is a well-known property of quasi-adiabatic flows, it has no reason to hold in the presence of diabatic heating. Hence, there is seemingly a contradiction between the observed preservation of the low PV-aerosol-tracer relationship over time and fundamental properties of PV in this diabatically-forced flow.

In this presentation, we propose a conceptual model for the formation and evolution of smoked-charged anticyclones. The mechanisms at play will first be illustrated using idealized numerical simulations with the Weather Research and Forecast (WRF) model where we explore for the first time the flow response to a Lagrangian tracer locally heating the atmosphere. We will then analyze key features of the observed anticyclonic structures reproduced by the model, including the maintenance of the anticyclonic tracer bubble along its ascent, the formation of a tracer front at its top and of a tail at its lower bound, and a very low, almost-vanishing PV within the vortex. Finally, we will discuss some implications of our findings, in particular regarding the dynamical conditions favoring the formation and maintenance of such structures.
Seismicity analysis in southern Ghana- I: Detecting local earthquakes by Deep Learning
Authors: Mohammadigheymasi Hamzeh , Tavakolizadeh Nasrin , Mousavi S. Mostafa , Silveira Graça , Fernandes Rui
Published: March 2022

A large volume of digital seismic data was recorded by six broadband seismic sensors equipped with GPS-clock timing in the Ghana Digital Seismic Network (GHDSN) between October 2012 and April 2014. For this period, no public seismicity catalog was reported by the global data centers, International Seismological Center (ISC), and United States Geological Survey (USGS) for southern Ghana. In this study, this database is processed to detect local earthquakes. To facilitate the challenging and time-consuming process of detecting the earthquakes and picking the arrival times of P and S phases, we utilize EQTransformer, a Deep Learning (DL) model deploying Hierarchical Attention Mechanism (HAM) for simultaneous earthquake detection and phase picking. This model utilizes global and local levels of attention mechanism for identifying earthquake and seismic phases deriving benefits from deep neural networks, including convolutional and recurrent neurons. The thresholding values of 0.2, 0.07, and 0.07 are set for earthquake detection, P-picking, and S-picking, respectively. As a result, a list of events for each station of the network with the associated time of detection, as well as P and S phase arrivals are obtained. Taking these arrival times into account, we have devised a so-called ”conservative strategy” to optimally extract all possible earthquakes in the data set, amenable to locate. Initially, a list of preliminary events recorded by at least two stations is created by comparing the earthquake occurrence and arrival times of the P and S phases for all stations regarding a 100 sec time threshold. The list in this step includes 317 events recorded by at least two stations. Eventually, an analyst controls the obtained waveforms in other stations assesses whether EQTranasformer misses the preliminary list of events in those stations. Consequently, a number of 533 picked phases (282 P and 251 S) recorded by a minimum of 3 stations are finalized. Incorporating these phases and removing the instrument response from the waveforms, the hypocentral parameters for 73 earthquakes with 2.5 ≤ M L ≤ 4.0 are estimated. The main concentration of events is on the intersection of the Akwapim fault zone and the coastal boundary fault, with some scattered seismicity along the Akwapim fault zone. The corresponding set of seismic phases is utilized to estimate an updated 1D crustal velocity model for the study area. This research contributes to the FCT-funded projects SHAZAM (Ref. PTDC/CTA-GEO/31475/2017), RESTLESS (Ref. PTDC/CTA-GEF/6674/2020), SIGHT (Ref. PTDC/CTA-GEF/30264/2017), and IDL (Ref. UIDB/50019/2020).
Assessing rainfall triggering of shallow landslides with an automatic tool generating thresholds: a case study for the Alpes-Maritimes region, France
Authors: Barthelemy Sophie , Bernardie Séverine , Grandjean Gilles
Published: March 2022

In this work, we use a probabilistic approach for modelling rainfall thresholds (Caine 1980) triggering shallow landslides with a case study for the Alpes-Maritimes region (France).

In particular, the CTRL-T algorithm (Melillo and al. 2018) is tested to output critical rainfall thresholds, based on the accumulated rainfall – duration parameters (E-D), for different exceedance probabilities from respectively a landslide and two climate datasets. The first climate dataset stores high resolution gridded rainfall data (1km resolution, hourly) and the second climate dataset contains lower resolution gridded rainfall, snow, temperature and evapotranspiration data (8km resolution, daily); the first dataset provides the rainfall records directly used for defining the rainfall events and then for the threshold construction; the second one enables to assess the region’s climate via parameters imported in CTRL-T. The thresholds are then validated using a method designed by Gariano and al. (2015).

Several improvements are made to the method. First, potential evapotranspiration values approximated from temperatures and latitudes in one of the process’ steps are replaced by values from the second climate dataset, the result accounting best for the regional climate. Then, climate-specific duration values, used to split the raw rainfall records in events and sub-events, are computed for each mesh point. This second modification enables considering the heterogeneity of the Alpes-Maritimes climate.

Rainfall thresholds are eventually obtained for different exceedance probabilities, first from a set of probable conditions (MRC), then from a set of highly probable conditions (MPRC). The validation process strengthens the analysis as well as enables to identify best performing thresholds. This work represents novel scientific progress towards landslide reliable warning systems by (a) making a case study of probabilistic rainfall thresholds for Alpes-Maritimes, (b) using for the first time high-resolution rainfall data and (c) adapting the method to climatically heterogeneous zones.
Rock-Eval®-RMQS: Monitoring the Characteristics of SOM on the French Territory with Rock-Eval® 6 Thermal Analysis to Assess its Stability
Authors: Delahaie Amicie , Barré Pierre , Baudin François , Arrouays Dominique , Bispo Antonio , Boulonne Line , Chenu Claire , Jolivet Claudy , Martin Manuel , Saby Nicolas , Savignac Florence , Cécillon Lauric
Published: March 2022

Soil organic matter (SOM) is widely recognized as of critical importance for both soil quality and climatic mitigation. The quality and quantity of SOM are key to assess the characteristics of soils, and thus must be accurately monitored in order to protect the integrity of soils. In the last few years, a thermal analysis technique called Rock-Eval® that provides insights on bulk SOM chemistry and thermal stability has been recognized as a powerful method for SOM characterization. It can moreover be applied on large sets of samples.

The RMQS is the French monitoring network of soil quality. The first sampling campaign took place from 2000 to 2015 and resulted – among others – in about 2200 composite surface (0-30 cm) samples taken all over France. It represents an unprecedented collection of precise and complete data on French soils.

We observed significant effects of land cover on both SOM thermal stability and bulk chemistry. The mean values of hydrogen index (HI, which is a proxy for SOM H/C ratio) for arable lands (190.5 ± 43.4 mg HC per g of SOC, n=786) was lower than for grassland soils (228.4 ± 46.3 mg HC per g of SOC, n=486) and forest soils (240.4 ± 66.4 mg HC per g of SOC, n=528). Regarding the oxygen index (OIre6, which is a proxy of SOM O/C ratio), we observed significantly different values (P<0.001) for arable land soils (188.8 ± 30.4 mg O2 per g of SOC), grassland soils (172.4 ± 26.8 mg O2 per g of SOC) and forest soils (164.2 ± 29.6 mg O2 per g of SOC). We also observed that thermal stability of SOM was significantly higher in cropland soils compared to grassland and forest soils. Our data suggest that topsoil SOM is on average more oxidized and biogeochemically stable in croplands. Further analyses will investigate the influence of pedo-climatic conditions on SOM characteristics.

The high number and even repartition of data on the French territory allow for the constitution of a national interpretative referential for these indicators. The Rock-Eval® parameters will also be used to calculate the centennially stable SOC fraction using the PARTYsocv2.0 model and map it at the scale of France.
Kinematic patterns of tectonic displacements in the Blue Clay outcrops along the eastern border of the Bradanic Trough (Southern Italy) from DTM data processing
Authors: Spilotro Giuseppe , Andriani Gioacchino Francesco , Di Prizio Giuseppe , Decaro Katia , Parisi Alessandro , Fidelibus Maria Dolores
Published: March 2022

The Bradanic Trough (Southern Italy) is the Pliocene-present-day south Apennines foredeep. It is filled by a thick Pliocene to Pleistocene sedimentary succession constituted by hemipelagites (Blue Clay Fm.) in the lower part, and coarse grained deposits (sands and conglomerates) in the upper part, shaped in marine or continental terraced environment.

On the eastern border of the Bradanic Trough along the Murgian Plateau (Apulia, Italy) numerous morphological lineaments are associated with sequential lowering and rotation of the surface, aligned with the carbonate substrate dip direction.

These morphologies have been interpreted so far as erosion products; their association with medium-deep water circulations and surface phenomena, like mud volcanoes, now allows their interpretation as a lumped mass, detached and tilted along shear surfaces.

The surface patterns of such surfaces may be easily detected for the presence, at some distance, of a quite similar twin track, which overlaps with good agreement.

The numerical analysis of the tracks extracted from accurate DTMs allows us to reconstruct the kinematic patterns of the tectonic displacement (distance of the detachment; rotation; angle of the shear plane). This type of analysis might reveal very useful in some fields of engineering geology, such as underground works, and for interpreting many hydrogeological phenomena within the study area. Finally, the correct 3D representation of the detached masses helps to identify the true causes of the direct faulting, which is not always linked to the tectonics, not active in the concerned regions.
When is numerical resolution high enough to resolve cold pool organization?
Authors: Fiévet Romain , Meyer Bettina , Haerter Jan
Published: March 2022

It is well-recognized that triggering of convective cells through cold pools is key to the organization of convection, as reviewed in Zuidema et al. (2017). Yet, numerous studies have found that both the characterization and parameterization of these effects in numerical models is cumbersome - in part due to the lack of numerical convergence (Δx→ 0) achieved in typical cloud-resolving simulators. Through a comprehensive numerical convergence study, we systematically approach the Δx→ 0 limit in a set of idealized large-eddy simulations capturing key cold pool processes: propagation, merging and collision of gust fronts. We characterize at which Δx convergence is achieved for physically relevant quantities, namely accumulated upwards water mass fluxes, integrated vortical rates and gust front's group velocity.

The gust front vortical size and strength achieves convergence at Δx=100m horizontal resolution (70% drop at Δx=800m), while the probability distribution of updraft fluxes upon frontal collision, ƒ(w), appears satisfactorily resolved at Δx=50m. Interestingly, ƒ(w) exhibits self-similarity as a function of Δx, down to the coarsest case of Δx=800m. A rescaling function is derived that successfully collapses all distributions onto a common solution. Further, the positive water mass perturbation caused upon propagation and collision of the gust front appears well-captured at Δx=200m (35% drop at Δx=800m). Finally, the incidental merging of several cold pools results in a large gust front, as often found in MCS. The group velocity of this merged front is only mildly dependent on resolution (10% drop at Δx=800m), suggesting that the numerical dissipation dominates over dispersion.

The understanding gained from this analysis lays the groundwork to develop robust subgrid models for CP dynamics able to sustain their growth and combat artificial numerical dissipation and dispersion.
Flood inundation mapping using Sentinel-1 SAR images with Google Earth Engine cloud platform
Authors: Wang Qin , Zhuo Lu , Rico-Ramirez Miguel , Han Dawei , Wang Jiao , Liu Ying , Du Sichan
Published: March 2022

Flood events are expected to become increasingly common with the global increases in weather extremes. The present state of the technologies for flood risk mapping is typically tested on small geographical regions due to limitation of flood inundation observations, which hinders the implementation of flood risk management activities. Synthetic aperture radar (SAR) sensors represent an indispensable data source for flood disaster planners and responders, given their ability to image the Earth's surface nearly independently of weather conditions and the time of day or night. The decision by the European Space Agency (ESA) Copernicus program to open data from its Sentinel-1 SAR satellites to the public marks the first time of global, operational SAR data freely available. Combined with the emergence of cloud computing platforms like the Google Earth Engine (GEE), this development presents a tremendous opportunity to the disaster response community, for whom rapid access to analysis-ready data is needed to inform effective flood disaster response interventions and management plans. Here, we present an algorithm that exploits all available Sentinel-1 SAR images in combination with historical Landsat and other auxiliary data sources hosted on the GEE to rapidly map surface inundation during flood events. Our algorithm relies on multi-temporal SAR statistics to identify unexpected floods in near real-time. Additionally, historical Landsat-based surface water class probabilities are used to distinguish unexpected floods from permanent or seasonally occurring surface water. The flexibility of our algorithm will allow for the rapid processing of future open-access SAR data, including data from future Sentinel-1 missions.
The Expander: Growing fault networks under pure shear conditions
Authors: Liu Jun , Rosenau Matthias , Brune Sascha , Kosari Ehsan , Oncken Onno , Rudolf Michael , Wrona Thilo
Published: March 2022

The growth of faults is well studied with field methods, experiments and theoretical models. Fault evolution is largely established from a geometrical and kinematic point of view with respect to the growth of isolated faults and their mutual interaction. However, the dynamics of fault growth (e.g. stress shadowing, damage zone evolution, energy budgets) and the emergence of interactions over various spatial and temporal scales in larger fault networks is a topic of recent interest less illuminated so far. We here introduce a new experimental setup allowing to study “large-n” fault networks evolving in crustal-scale brittle and brittle-ductile analogue models. We document preliminary results helping to demonstrate and verify the capability of the approach.

The setup, called “The Expander”, builds on a traditional extensional setup with a basal rubber sheet expanded in one direction. The aspect ratio of the rubber sheet controls its lateral contraction (“Poisson’s effect”) and thus the bulk strain ratio under pure shear conditions. We can thus realize constrictional (prolate) to plane to flattening (oblate) kinematic basal boundary conditions depending on the sheet’s aspect ratio and whether we expand or relax the sheet. Evolving fault networks vary from anastomosing fold-and-thrust belts to conjugate sets of strike-slip fault networks to quasi-parallel normal fault populations, respectively. We apply digital image correlation (DIC) to track the kinematic surface evolution and photogrammetry (structure from motion, SFM) for topography evolution.

First observations suggest that strike-slip fault networks in a purely brittle crust under basal pure shear conditions evolve into compartments of synthetic faults, the size of which scale with brittle layer thickness similar to fault spacing. The scaling seems to be controlled by slip partitioned onto the individual faults and mediated by stress shadows. Numerical simulation of the experiment suggests that the compartmentalization might evolve further through sequential de-activation of smaller faults and collapse of deformation into a single regional scale master fault with or without prescribing a zone of crustal weakness (a “seed”). Further experiments are planned to test the fault pattern evolution for different mechanical stratigraphy (brittle-viscous layers, seeds) and kinematic boundary conditions.
Assessing the environmental impact of combined sewer overflows through a parametric study
Authors: Farina Alessandro , Di Nardo Armando , Gargano Rudy , Greco Roberto
Published: March 2022

Design and management of combined sewer overflows (CSO) have been, so far, mainly based only on complying a fixed dilution rate of wastewater in stormwater during rain events. This poses serious environmental issues since the definition of the acceptable dilution (i.e. overflows are usually designed for activation when Q > ~5Qmw, the latter being the mean dry weather wastewater discharge) does not consider the characteristics of the upstream urban catchment nor those of the receiving water body. Accordingly, more recent regulations started enforcing limits also on the yearly number of overflows or increasing dilution coefficient.

Overflows activation frequency and discharged volumes of pollutants may depend on the upstream catchment features as well as on the precipitation regime. The great variability of these factors could make the impact on the receiving water body of similarly designed overflows to be quite different.

In this study, the behaviour of a CSO with fixed dilution rate placed at the outlet of urban catchments with same size, but different hydrological and urbanistic characteristics, has been simulated through SWMM multi-scenario simulations. The considered hydrological parameters were catchment imperviousness, width, slope, routing Manning coefficient and depression storage for both pervious and impervious surfaces. Urbanistic characteristics of the catchment affecting the combined sewer hydraulic regime were studied by changing the density of population, the imperviousness, and the mean per capita wastewater discharge.

After defining realistic ranges for each parameter, the time series of discharged overflows have been calculated for all the combinations of the variable catchment parameters, corresponding to 20 years long precipitation time series of a single rain gauge.

The obtained results indicate that CSOs impact on the receiving water body, strongly depends on the characteristics of the upstream urban catchment. Therefore, such characteristics should be considered in CSO design and management.
Seismic retrofit policies and their effectiveness for rural earthen dwellings in China: lessons from the Yunnan Province case study
Authors: Wang Yaan , Wang Ming , Liu Kai , Galasso Carmine
Published: March 2022

Earthen dwellings are highly vulnerable to earthquake-induced ground shaking and are widely distributed in earthquake-prone and underdeveloped rural areas in the Yunnan Province, China. In the past 30 years, 78 earthquakes with a surface-wave magnitude (Mw) greater than 5.0 struck Yunnan Province, with rural earthen dwellings contributing the most to casualties and building damages. In recent years, national and local governments in China promulgated various seismic retrofit and risk mitigation policies for rural areas, along with seismic retrofit techniques gradually being implemented in practice.

This presentation will review policies and seismic retrofit techniques for rural earthen dwellings in Yunnan Province, discussing their seismic mitigation effectiveness based on a post-disaster field survey of the Mw 6.1 Yangbi earthquake in May 2021 and other historical earthquake disaster data. Comparisons of (1) the damage states of earthen dwellings with and without retrofit; and (2) statistical damage data of earthen dwellings during the Yangbi earthquake and historical earthquakes are analyzed and discussed in detail.

The analysis results show that the seismic retrofit measures effectively mitigated the seismic effect on rural earthen dwellings and greatly improved rural communities' resilience. Lessons learned are highlighted, and recommendations from the study are finally proposed.
Understanding and quantifying fire-vegetation interactions through integrating satellite observation data with the Dynamic Land Ecosystem Model (DLEM)
Authors: Li Xiaoyong , Tian Hanqin , Yang Jia , You Yongfa , Pan Shufen
Published: March 2022

Fires play a critical role in global biogeochemical and hydrological cycles through influencing vegetation succession and ecosystem functioning. Observational evidence shows that fire regimes across global ecosystems have been altered by climate change and human activities. However, most fire-enabled terrestrial biosphere models (TBMs) poorly capture the spatial and temporal patterns of fire ignitions, burned area, vegetation mortality and post-fire recovery. To improve our ability in predicting fire behavior and its impacts on the ecosystem and climate, it is essential to better represent fire-vegetation interactions in TBMs. Here, we improve the fire module of the Dynamic Land Ecosystem Model (DLEM-Fire) and optimize the parameters by using the satellite observed fire ignitions, burned area and leaf area index (LAI) products. Our results show that the improved fire model can describe the magnitude, spatial patterns, and interannual variations of burned area and vegetation mortality more accurately. Moreover, the model is capable of providing robust estimations of post-fire vegetation regeneration to characterize the vegetation resistance and resilience to fire disturbances. This study emphasizes the importance of integrating terrestrial biosphere models and satellite observation data for fire monitoring and prediction.
Developing a new method for long-term monitoring of the weathering of historical building materials
Authors: Germinario Luigi , Coletti Chiara , Choidis Petros , Kraniotis Dimitrios , Maritan Lara , Sassi Raffaele , Tositti Laura , Mazzoli Claudio
Published: March 2022

This contribution presents the work of research and technical development for designing a novel method for monitoring and predicting the weathering of cultural heritage, in particular of stones and timber used historically as building materials.
An apparatus for long-term field tests was designed in its hardware and software components with a twofold application:

Exposure of a set of selected stone and wood specimens to natural weathering, at different orientations (North, South, and horizontal plane) and environmental settings (Italy and Norway).

Non-stop acquisition of microclimate data series at different resolutions, down to the scale of the specimen surface, completed by datasets of regional stations of environmental monitoring.

Complementary laboratory analyses aim at setting a reference point for the state of conservation of each material before the exposure tests, and monitoring the changes of surface recession/topography (by 3D optical profilometry), thus reconstructing the relevant deterioration trends.
Within the framework of the EU-funded project HYPERION, this novel experimental approach is expected to help assessing the interaction of building materials with the environment and their weathering constrained by microclimate and climate variability; combining climate model simulations, the stresses brought about by climate change can also be assessed. The findings might represent a source of precious information for the activities and decision-making protocols of the stakeholders involved in the protection of cultural heritage.
Observation-based modelling of the energetic storm particle event of 14 July 2012
Authors: Wijsen Nicolas , Aran Angels , Scolini Camilla , Lario David , Afanasiev Alexandr , Vainio Rami , Pomoell Jens , Sanahuja Blai , Poedts Stefaan
Published: March 2022

In this work, we model the energetic storm particle (ESP) event of 14 July 2012 using the energetic particle acceleration and transport model named PARADISE (PArticle Radiation Asset Directed at Interplanetary Space Exploration), together with the solar wind and coronal mass ejection (CME) model named EUHFORIA (EUropean Heliospheric FORcasting Information Asset).  The CME generating the ESP event is simulated by using the spheromak model of EUHFORIA, which approximates the CME’s magnetic field as a linear force-free spheroidal magnetic field. The energetic particles are modelled by injecting a seed population of 50 KeV protons continiously at the CME-driven shock wave. The simulation results illustrate both the capabilities and limitations of the utilised models.  

We find that for energies below 1 MeV, the simulation results agree well with the upstream and downstream components of the ESP event observed by the Advanced Composition Explorer (ACE).  This suggests that these low-energy protons are mainly the result of interplanetary particle acceleration. In the downstream region, the sharp drop in the energetic particle intensities is reproduced at the entry into the following magnetic cloud, illustrating the importance of a magnetised CME model.

This research has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 870405 (EUHFORIA 2.0).
Understanding extreme events with multi-thousand member high-resolution global atmospheric simulations
Authors: Watson Peter , Sparrow Sarah , Ingram William , Wilson Simon , Zappa Giuseppe , Bevacqua Emanuele , Leach Nicholas , Sexton David , Jones Richard , Drouard Marie , Mitchell Daniel , Wallom David , Woollings Tim , Allen Myles
Published: March 2022

Multi-thousand member climate model simulations are highly valuable for showing characteristics of extreme weather events in historical and future climates. However, until now, studies using such a physically-based approach have been limited to using models with a resolution much coarser than the most modern systems. We have developed a global atmospheric model with ~60km resolution that can be run in the climateprediction.net distributed computing system to produce such large datasets. This resolution is finer than that of many current global climate models and sufficient for good simulation of extratropical synoptic features such as storms. It also allows many extratropical extreme weather events to be simulated without requiring regional downscaling. We will show that this model's simulation of extratropical winter weather is competitive with that in other state-of-the-art models. We will also present the first results generated by this system. One application has been the production of ~2000 member simulations based on sea surface temperatures in severe future winters produced in the UK Climate Projections 2018 dataset, generating large numbers of examples of plausible extreme wet and warm UK seasons. Another is showing the increasing spatial extent of precipitation extremes in the Northern Hemisphere extratropics. 
Sensitivity of tropical cyclone formation to moisture patterns in monsoon and easterly environments over the western North Pacific
Authors: Teng Hsu-Feng , Kuo Ying-Hwa , Done James M.
Published: March 2022

This study explores the sensitivity of tropical cyclone (TC) formation to moisture in monsoon and easterly environments over the western North Pacific in regional forecasts. The Weather Research and Forecasting (WRF) Model is used to simulate 22 TCs that form in monsoon environments (Monsoon-TCs) and 13 TCs that form in easterly environments (Easterly-TCs) over the period 2006–2010. To characterize the moisture contribution, forecasts with moisture improved through assimilation of global positioning system (GPS) radio occultation (RO) data (EPH experiment) are compared to those without (GTS experiment). In general, the hit rate of TC formation forecast is higher for monsoon environments than easterly environments, regardless of GTS or EPH, especially for the monsoon trough. In total, 54% of Easterly-TC formation forecasts are sensitive to the improved moisture patterns, while only 18% for Monsoon-TC formation forecasts are sensitive. This indicates that the importance of moisture patterns is relatively higher for Easterly-TC formations. Conversely, during the monsoon trough active phase, the importance of vorticity improved through assimilation of GPS RO data is relatively higher for overall TC formation forecast skill.
Wet – wetter – weather: Attributing Global Precipitation to weather features
Authors: Konstali Kjersti , Sorteberg Asgeir , Spensberger Clemens , Weijenborg Chris , Lutzmann Johannes , Spengler Thomas
Published: March 2022

Precipitation has increased globally in the mean during the past century and is expected to continue to increase with rising temperatures. In the mid- to high latitudes, extratropical cyclones, fronts, atmospheric rivers, and cold air outbreaks are associated with a substantial fraction of the total precipitation. As these weather features might respond differently to a changing climate, investigating precipitation changes in the context of weather systems provides further insight into the observed changes in precipitation. Therefore, we introduce a new method for attributing precipitation to weather features. The method allows us to decompose total precipitation into the respective contributions by extratropical cyclones, fronts, atmospheric rivers, cold air outbreaks, and their combinations.

We have classified precipitation between 1930-2010 in the ECMWF’s twentieth century reanalyses project, ERA-20C. Our method assigns 70% of the total precipitation poleward of 30° to the aforementioned categories, allowing us to assess the relative importance of these weather features for total precipitation and for precipitation extremes. We find that the combination of extratropical cyclones, fronts, and atmospheric rivers accounts for more than 50% of the total precipitation and for 90% of the extreme events in the northern hemisphere storm-track regions, despite these precipitation events occurring less than 20% of the time.
Sea level, bottom pressure, gyres and overturning: lessons from classical models.
Authors: Hughes Chris W.
Published: March 2022

Even in models with vertical sidewalls, bottom pressure torques balance the wind stress curl in a zonal integral, with local modification from nonlinear terms. This can be seen explicitly in Stommel's classic 1948 solution in which, unusually, the sea level was calculated as well as the barotropic streamfunction. Here, I explore what this and other idealised solutions tell us about how coastal sea level relates to gyre circulations, western boundary currents, and simple overturning circulations. I show that the coastal sea level signal related to the gyre (or, particularly, to changes in the gyre) need not be stronger at the western boundary. I also show that, although details of where dissipation occurs can be very important for coastal sea level when sloping sidewalls are accounted for, they are much less important for the boundary bottom pressure torque (in the vertical sidewall case, sea level and torque are closely related, so the influence of dissipation on sea level is diminished). Although the real ocean will inevitably be more complex than these ideal cases, consideration of them does alter common assumptions about how coastal sea level is likely to respond to changing circulation patterns, in response to changing climatic forcing.

 
Learning and screening of neural networks architectures for sub-grid-scale parametrizations of sea-ice dynamics from idealised twin experiments
Authors: Finn Tobias , Durand Charlotte , Farchi Alban , Bocquet Marc , Chen Yumeng , Carrassi Alberto , Dansereau Veronique
Published: March 2022

In this talk, we propose to use neural networks in a hybrid modelling setup to learn sub-grid-scale dynamics of sea-ice that cannot be resolved by geophysical models. The multifractal and stochastic nature of the sea-ice dynamics create significant obstacles to represent such dynamics with neural networks. Here, we will introduce and screen specific neural network architectures that might be suited for this kind of task. To prove our concept, we perform idealised twin experiments in a simplified Maxwell-Elasto-Brittle sea-ice model which includes only sea-ice dynamics within a channel-like setup. In our experiments, we use high-resolution runs as proxy for the reality, and we train neural networks to correct errors of low-resolution forecast runs.

Since we perform the two kind of runs on different grids, we need to define a projection operator from high- to low-resolution. In practice, we compare the low-resolution forecasted state at a given time to the projected state of the high resolution run at the same time. Using a catalogue of these forecasted and projected states, we will learn and screen different neural network architectures with supervised training in an offline learning setting. Together with this simplified training, the screening helps us to select appropriate architectures for the representation of multifractality and stochasticity within the sea-ice dynamics. As a next step, these screened architectures have to be scaled to larger and more complex sea-ice models like neXtSIM.
Interest of the Assimilation of Surface Melt Extent Derived From Passive and Active Microwave Satellites Into the Regional Climate Model MAR Over the Antarctic Peninsula
Authors: Dethinne Thomas , Kittel Christoph , Glaude Quentin , Fettweis Xavier , Orban Anne
Published: March 2022

Melting ice sheets are a major contributor to the rising sea level. At the Liège University, the Regional Climate Model MAR (Modèle Atmosphérique Régional) has been developed to monitor and study the current and future evolution of various properties of ice sheets. However, uncertainties remain on the surface melt extent upon Antarctic ice sheets as models are subject to error propagation and need some external data to model the climate.

In Antarctica, unlike Greenland, the produced surface meltwater does not leave the ice sheet through visible rivers in which the quantity of meltwater can be estimated. Remote sensing is then the only product able to provide an estimation of the surface melt extent with a satisfying spatial and temporal coverage. The assimilation of melt spatial extent estimated by remote sensing allows the mitigation of the uncertainties linked to the models as well as a better quantification of the melt quantity.

In this research, active (Sentinel-1) and passive (AMSR2 & SSMIS) microwave satellite data are assimilated into MAR model over the Antarctic Peninsula, where surface melt has caused hydrofracturing and destabilization of ice shelves in the past. The assimilation of the different satellite products is also conducted to study the effect of spatial resolution on melt detection, Sentinel-1 having a pixel size of a few meters while passive satellites are at the 10km scale. This difference can be crucial upon the Peninsula as Foehn effects are occurring locally and can generate local surface melt, not detectable while using a coarser resolution.
1000 years of climate history from a coastal West Antarctic ice core site
Authors: Rowell Isobel , Mulvaney Robert , Wolff Eric , Pryer Helena , Tetzner Dieter , Thomas Liz , Rix Julius , Martin Carlos
Published: March 2022

Few ice cores from the Amundsen and Bellingshausen sectors of the West Antarctic Ice Sheet (WAIS) extend back in time further than a few hundred years. The WAIS is believed to be susceptible to collapse as a result of anthropogenic climate change. Modelling studies and palaeoclimatic evidence have suggested at least partial WAIS collapse and resulting sea level rise during previous warm periods, therefore understanding the stability of the WAIS during warm periods is important. The WACSWAIN project successfully drilled a 651 m ice core on Skytrain Ice Rise, adjacent to the Ronne Ice Shelf, in 2018, some data from which are now being published. The second WACSWAIN drilling project took place in 2020 on Sherman Island in the Abbott Ice Shelf, where the British Antarctic Survey’s (BAS) Rapid Access Isotope Drill (RAID) was deployed. The team drilled a 323 m deep borehole, with discrete samples of ice chippings collected from the entire depth range of the drilled ice. The samples were analysed for water isotopes and major ion content at BAS from 2020-2022. Validation of the RAID-ice data is confirmed through comparison with a shallow core drilled on Sherman Island during the same field campaign. Using annual layer counting of chemical records and volcanic horizon identification, an age scale for the record of 1724 discrete samples is presented. The Sherman Island ice record extends back to at least 1000 years before present, providing the oldest ice-derived continuous palaeoclimate record for the coastal Amundsen-Bellingshausen sector to date. An estimation of accumulation history at the site is presented. A comparison of the longer chemical and water isotope records with other regional ice cores provides insights into the spatial variability of change over recent centuries. Climate trends in the region of the Amundsen sea glaciers (including Thwaites) - considered the most vulnerable to future warming - are investigated.
The inclusion of Geoethical Values in the Design of Educational Policy for the Next Decade: The Case of the Greek Educational System
Authors: Georgousis Efthymios , Savelidi Maria , Savelides Socrates , Mosios Spyros , Holokolos Maximos-Vasileios , Drinia Hara
Published: March 2022

The inclusion of geoethics in the curricula contributes to young people's reflection on personal and social values and responsibilities, in order to raise awareness and develop appropriate behavior regarding the interaction of human activities with the Earth system (Georgousis et al., 2021; 2022). In modern societies, educational policy is implemented with the curricula being the mainspring. Recently, the new educational curricula that reflect the directions of educational policy in Greece for the next decade were prepared and announced. These curricula have received and are subject to various criticisms from scientific reviews of academic committees and educational institutions. In the midst of these, the question of whether they incorporate values of the natural world related to Geology and geoethical thought was developed, namely whether in an indirect and direct way they contribute to the sensitization and empowerment of students to the values of geoethics and consequently to the formation of environmentally and socially aware citizens. In order to answer this concern, research questions were posed regarding the presence of conceptual patterns, which refer to obvious or latent meanings for the promotion of geoethical values through the educational process. The methodology followed is the qualitative strategics with the technique of sensitizing content analysis, aimed to explore the thematic units and the expected learning outcomes of the new curricula of compulsory education of the Greek educational system. The texts were examined with the paragraph as the thematic unit. The characterization of the quantity was based on linguistic scales of related studies, according to which the results were characterized, identified and documented as they were estimated by the authors of the study. Computer-assisted qualitative data analysis software (CAQDAS) was used for the content analysis, specifically the quantification of the meaning patterns. Sixteen (16) new curricula were investigated. The investigation identifies a relatively small number of obvious conceptual patterns (codes) and a greater number of latent meanings in both social and natural sciences, revealing the limited potential for the development of geoethical thinking and geoethical values. Therefore, the lack of integration of geoethical values in the curricula of the next decade is noted, although recent researches document the lack of understanding of the geological heritage and the necessity for developing geoethical awareness of young people through the educational process.