bluuebunny/crossref_metadata_2025 huggingface dataset:
Variability of the Surface Solar Radiation over Reunion island and its interaction with the synoptic, intraseasonal and interannual convective variability
Authors: Tang Chao , Mialhe Pauline , Pohl Benjamin , Morel Béatrice , Koseki Shunya , Abiodun Babatunde , Bessafi Miloud
Published: March 2022

The impacts of large scale climate variabilities on the solar energy resource are widely investigated around the world, however their effects are not yet clear for Mascarene Islands (southwest Indian Ocean, SWIO) and needs to be addressed. In this study, surface solar radiation (SSR) classification and anomalies at the diurnal scale from SARAH-E satellite product over Reunion Island are linked to the large scale climate variabilities in SWIO region. These climate variabilities include Tropical Cyclones (TCs) and the Tropical Temperate Troughs (TTTs) at the synoptic scale, the Madden–Julian Oscillation (MJO) at the intraseasonal scale, and the Indian Ocean Dipole (IOD), the Subtropical Indian Ocean Dipole (SIOD) and the El Niño–Southern Oscillation (ENSO) at the interannual scale.
We identified the variability of SSR at various time scales where both local processes and the large scale convective variabilities play important roles. At the synoptic and intraseasonal timescales, the local variability of SSR over Reunion shows a significant association with TCs, TTTs and the MJO. The sign and amplitude of SSR diurnal anomaly are found to be correlated with the enhanced- / depressed- convective phase and amplitude of these events. The SSR anomaly is strongly altered with the presence of nearby TCs, with a value of up to about 30% of climatology, although at low occurrence; TTTs and MJO have relatively weaker impact, with a value of about 13% and 5% respectively. At the interannual timescale, IOD, SIOD and ENSO have relatively much less importance on local SSR variability. The daily total solar energy density has been calculated for all these variabilities to provide useful information for energy applications. 
A Plausible Explanation for Common Fractal Temporal-Spectral Slopes of Drainage Flows and Chemistries at Full-Scale Mining Operations
Authors: Morin Kevin
Published: March 2022

Where full-scale minesite-drainage monitoring has been carried out at sufficiently high sampling frequencies and long durations, interesting and intriguing patterns have been seen in the time series.  Some observations include: flow rates and aqueous concentrations of minesite drainages are not simple or steady; they are not stochastic, but also not deterministic; they are not random or chaotic. They display periodicity in complex ways.

Based on spectral analyses of time series for minesite drainages as well as for non-mining-related rivers and catchments, the typical trend is decreasing spectral power of the peaks with decreasing wavelength.  The resulting slopes are commonly fractal, typically ranging between zero (random) to 2 (random walk).  The slope of 1 ("1-over-f") is the most complex and yet has been documented in many sciences and arts.  These fractal slopes are “ubiquitous” in some non-mining catchments.

Consistent with Earth-System Science, electrical fields in the Earth are inevitably linked to other processes like large and small physical movements, magnetic variations in the earth, weather systems, and cosmic radiation.  For example, the movement of natural water through a porous or fractured medium can create an electrical field that in turn affects the distribution of ions in that water.  Small changes in ground electrical potential, considered minor background electrical "noise" by some, can significantly affect aqueous chemistry.

This study asks the question, “Why?”  Why are fractal spectral slopes so common in drainage flows and chemistries whenever data have been sufficient to search for them?

A plausible answer begins with the fact that many minesite components are open systems in the surficial environment, well grounded to the earth which behaves like an electrical capacitor.  Thus, relatively large minesite components can act as first-order low-pass signal filters.  These filters cause the spectral powers of individual periodicities entering them to (1) decrease along a fractal slope of 2 at wavelengths shorter than the "cutoff wavelength" and (2) remain unfiltered at longer wavelengths.  When several mechanisms are simultaneously acting and overlapping as low-pass filters, fractal slopes including 1-over-f slopes can appear.  Based on this rationale, periodic processes grounded to the Earth can show fractal temporal slopes when sufficient data are collected.
Intra-plate seismicity of the Lake Eyre Basin and Gawler Craton, Australia
Authors: Eakin Caroline , Agrawal Shubham , O'Donnell John Paul
Published: March 2022

The Australian continent, being void of plate boundaries, is often perceived as seismically quiescent. However, around 100 magnitude three or larger earthquakes are typically recorded in Australia each year, with a magnitude 6+ occurring every 8-10 years. Such intra-plate activity can pose a significant risk as they are often non-periodic, poorly understood, and sporadically recorded by sparse seismic networks across vast continents. Within Australia the distribution of intra-plate seismicity is non-uniform, but instead tends to concentrate along certain weak zones of increased activity. One such region is the eastern margin of the Gawler Craton in South Australia, one of the oldest building blocks of the continent. Recently several new temporary seismic arrays have been deployed in the region, transforming data coverage across South Australia. So far over 70 new local events have been recorded that would otherwise have gone undetected by the national network. After relocation the pattern of earthquakes becomes more spatially defined and appears to be closely tied to the edge of the Gawler Craton. Supporting evidence suggests that these events may be associated with a trans-crustal scale fault system that adds new constraints on the poorly defined craton boundary.
Modular Assessment of Rainfall–Runoff Models Toolbox (MARRMoT) v2.1: better, faster and more accessible hydrological modelling through object-oriented programming.
Authors: Trotter Luca , Knoben Wouter , Fowler Keirnan , Saft Margarita , Peel Murray
Published: March 2022

The Modular Assessment of Rainfall–Runoff Models Toolbox (MARRMoT) is a flexible framework for hydrological modelling designed for model intercomparison studies and hypothesis testing. It reproduces 47 established conceptual hydrologic models of varying complexity including Sacramento, HBV, GR4J, VIC and TOPMODEL, amongst others. The package also allows to modify them or create new ones by mixing-and-matching components and modules from different models. We radically restructured MARRMoT compared to versions v1.x using an object-oriented programming approach to enhance code clarity and computational efficiency.

MARRMoT v2.1 is structured around two hierarchical classes, where a high-level superclass provides the template of all common model operations, while model-specific code is defined into individual subclasses derived from the single superclass. This reduces the verbosity and repetitiveness of the code, improving readability and facilitating debugging. Additionally, it simplifies the procedure to modify model structures or create new ones, also ensuring that best practices for solving model equations are followed as these are contained in the definition of the superclass and deployed automatically across all models.

We also updated MARRMoT’s numerical solving routine by including a Newton-Raphson solver. This lets us obtain satisfying solutions to the implicit Euler approximations of the models’ differential equations in a number of cases where the previous solving routine had failed, while also obtaining a 2.6-fold runtime improvement on average. We tested these changes by comparing outputs of 36 of the models in the framework between this object-oriented version and the previous version (v1.4) using calibrated parameters and climate inputs from the CAMELS US dataset.

The new version of the toolbox (v2.1) and user manual, including several workflow examples for common application, is available from GitHub (https://github.com/wknoben/MARRMoT).
Local meridional circulation changes contribute to a projected slowdown of the Indian Ocean Walker circulation
Authors: Sharma Sahil , Ha Kyung Ja , Cai Wenju , Chung Eui-Seok , Bódai Tamás
Published: March 2022

The weakening of zonal atmospheric circulation, a widely accepted projection of climate change in response to global warming, features a weakening of the Indian Ocean Walker circulation (IWC), with an anomalous ascending motion over the western and anomalous descending motion over the eastern Indian Ocean.  The projected IWC weakening has previously been attributed to slower warming in the east than the west, that is, to a positive Indian Ocean Dipole (IOD)-like warming pattern.  However, such a warming pattern can also be induced by IWC weakening. As a result, the cause-and-effect relationship cannot be easily determined, and the projected change is poorly constrained and highly uncertain. Here, using a suite of coupled climate model simulations under a high-emission scenario, we find that the IWC slowdown is accompanied by not only a positive IOD-like warming pattern but also anomalous meridional circulation that is associated with anomalous descending motion over the eastern Indian Ocean. We further show that the anomalous local meridional circulation is closely linked to enhanced land-sea thermal contrast and is unlikely to result from the positive IOD-like warming pattern, suggesting that the IWC weakening is in part driven by the anomalous local meridional circulation. Our findings underscore the important role of local meridional circulation changes in modulating future IWC changes. 
Quantifying glacier area changes using object-based image analysis in Google Earth Engine
Authors: Ali Asim , Dunlop Paul , Coleman Sonya , Kerr Dermot , W McNabb Robert , Noormets Riko
Published: March 2022

Glaciers are an important component of the cryosphere and are key indicators of climate change. Observations of temporal changes in glacier extent are essential for understanding the impacts of climate change, but these observations are not widely available in many parts of the world. Research indicates that climate change has had a significant impact on glacier recession, particularly in the Arctic, where glacier meltwater is an important contributor to global sea-level rise. Therefore, it is important to accurately quantify glacier recession within this sensitive region. In this study, we mapped 480 glaciers in Russian Arctic, Novaya Zemlya, using object-based image analysis (OBIA) applied to multispectral Landsat satellite imagery in Google Earth Engine (GEE) to quantify the area changes between 1986-89 to 2019-21.  Our results confirm that in 1986-89, the total glacierized area was 22958.98 km2 and by 2019-21 there was an 5.56% reduction in glacier area to 21680.63 km2.  Comparison between manually corrected glacier outlines taken from the Randolph Glacier Inventory (RGI) and the mapped glacier outlines derived using the OBIA method shows there is a 90.26% similarity between both datasets. This confirms that OBIA, combined with the GEE platform, is a promising method for accurately mapping glaciers, reduces the time required for manual correction, and can be applied in other glacierized regions for rapid assessment of glacier change.
Towards physics-informed stochastic parametrizations of subgrid physics in ocean models
Authors: Kondrashov Dmitri
Published: March 2022

All oceanic general circulation models (GCMs) include parametrizations of the unresolved subgrid-scale (eddy) effects on the large-scale motions, even at the (so-called) eddy-permitting resolutions. Among the many problems associated with the development of accurate and efficient eddy parametrizations, one problem is a reliable decomposition of a turbulent flow into resolved and unresolved (subgrid) scale components. Finding an objective way to separate eddies is a fundamental, critically important and unresolved problem. 
Here a statistically consistent correlation-based flow decomposition method (CBD) that employs the Gaussian filtering kernel with geographically varying topology – consistent with the observed local spatial correlations – achieves the desired scale separation. CBD is demonstrated for an eddy-resolving solution of the classical midlatitude double-gyre quasigeostrophic (QG) circulation, that possess two asymmetric gyres of opposite circulations and a strong meandering eastward jet, such as the Gulf Stream in the North Atlantic and Kuroshio in the North Pacific. CBD facilitates a comprehensive analysis of the feedbacks of eddies on the large-scale flow via the transient part of the eddy forcing. A  `product integral' based on time-lagged correlation between the diagnosed eddy forcing and the evolving large-scale flow, uncovers robust `eddy backscatter' mechanism. Data-driven augmentation of non-eddy-resolving ocean model by stochastically-emulated eddy fields allows to restore the missing eddy-driven features, such as the merging western boundary currents, their eastward extension and low-frequency variabilities of gyres.

N. Argawal, Ryzhov, E.A., Kondrashov, D., and P.S. Berloff, 2021: Correlation-based flow decomposition and statistical analysis of the eddy forcing, Journal of Fluid Mechanics, 924, A5. doi:10.1017/jfm.2021.604

N. Argawal, Kondrashov, D., Dueben, P., Ryzhov, E.A., and P.S. Berloff, 2021: A comparison of data-driven approaches to build low-dimensional ocean models, Journal of Advances in Modelling Earth Systems, doi:10.1029/2021MS002537

 
Dissecting the subseasonal and altitudinal water balance of a high-elevation Himalayan catchment using a land surface model
Authors: Buri Pascal , Fatichi Simone , Shaw Thomas E. , Miles Evan S. , McCarthy Michael , Fyffe Catriona , Fugger Stefan , Ren Shaoting , Kneib Marin , Fujita Koji , Pellicciotti Francesca
Published: March 2022

The snow and glacier reservoirs of High Mountain Asia play a key role in sustaining water supply to mountain communities and downstream ecosystems, populations and economic activities. However, little is known about how rain, snow- and ice melt vary sub-seasonally and along the altitudinal gradient in high-elevation watersheds.

We generate detailed simulations of catchment hydrology using a land surface model that constrains energy and mass fluxes using advanced physical representations of both cryospheric and biospheric processes in high detail at 100 m spatial resolution. We use the model to study how snow and glacier processes affect the hydrological cycle and how vegetation can mediate water yield from the high mountains of a glacierized Himalayan catchment downstream. This bridges the modelling gap between snow- and glacier dynamics, which generate the runoff, and vegetation processes, which interfere with runoff production and water uses at lower elevations.

We study the upper Langtang catchment (~4000-7000 m a.s.l.) in the Nepalese Himalayas, and simulate catchment runoff for two hydrological years (2017-2019), revealing the relative importance of precipitation, snow, ice, soil moisture and vegetation for different elevations and seasons. The land surface model is forced with hourly meteorological input data based on the main weather station in the basin and air temperature and precipitation were spatially distributed using observed elevational gradients. 

We calibrate a minimal set of parameters (physical properties of supraglacial debris) and use integrative variables such as catchment runoff or glacier mass balance only for validation. The availability of a rich dataset of field- and remote sensing observations allows validation of numerous physical processes simulated by the model and drastically reduces the probability of internal error compensation.

The model provides detailed insights into the importance of each of the energy and mass balance components in the catchment water budget and shows that evaporative fluxes are non-negligible contributors to mass loss at very high elevations (especially from snow) and in the lower part of the catchment (transpiration from vegetation). Often neglected or derived as a bulk quantity in simpler model approaches, evaporation accounts for about 15% of the water leaving the basin. We show precipitation to be the major source of uncertainty in the simulations and that vegetation is relevant in determining the amount of runoff transferred further downstream even for high elevation, extensively glacierized Himalayan catchments.
First analysis of shallow tremors in the Guerrero seismic gap.
Authors: Plata-Martinez Raymundo , Ito Yoshihiro
Published: March 2022

The Guerrero seismic gap, at the Mexican subduction zone, has been a region of great seismological interest because of the absence of a large earthquake in more than 110 years. If an earthquake were to rupture the entire Guerrero seismic gap the resulting earthquake could be disastrous to major Mexican cities. Additionally, the Guerrero subduction zone has plenty of slow earthquake activity with large slow slip events and tectonic tremors, located at the deep plate interface. To obtain a new and unique observation point of seismicity in the Guerrero seismic gap and continue evaluating its seismic risk, we deployed an array of ocean bottom seismometers (OBS) offshore the Guerrero seismic gap. We were able to detect and locate shallow tremors near the trench and deduce that a portion of the shallow plate interface undergoes stable slip. We used data from the OBS to analyse the new catalogue of shallow tremors and describe their source. Focal mechanisms of shallow tremors were estimated using S wave polarisation. We found that slip azimuth tends to follow the subduction plate motion, suggesting that tremors rupture at the plate interface. We also estimated shallow tremor radiated seismic energy. We found a heterogeneous energy release of shallow tremors along strike. Our observations of a heterogeneous shallow tremor energy release can be explained with the different mechanical properties, inside and outside the Guerrero seismic gap, and help to characterise the seismogenic zone at the shallow plate interface.
Real-time air mercury response from sediment-covered, volcanogenic massive sulphide mineralization on southern Vancouver Island, British Columbia, Canada.
Authors: Rukhlov Alexei S. , Mashyanov Nikolay R. , Pitirimov Pavel V. , Hickin Adrian S. , Golovetskyy Maksym , Coats Ben
Published: March 2022

New data from the Lara-Coronation polymetallic occurrence, southern Vancouver Island, British Columbia, Canada confirm that direct and continuous analysis of gaseous elemental mercury (GEM) concentrations in near-surface air using a portable RA-915M Zeeman Hg analyzer can instantly delineate mineralized zones that are buried beneath overburden 10s of m thick. Real-time grid sampling of air 1 cm above ground across steeply dipping, massive sulphide zones in volcanic rocks of the McLaughlin Ridge Formation (Sicker Group; Middle to Late Devonian) reveals a pattern of northwest-trending GEM haloes that reflect bedrock structure, including a 224 by 30 m halo above the polymetallic Coronation zone, covered by up to 22 m of overburden. Measured GEM concentrations range from 0.61 to 251 ng·m-3 in this study, with the strongest halo (206x background Hg) above exposed mineralization. Weak haloes (1.7x background Hg) mark sediment-covered mineralized zones. Before sampling GEM above overburden, we disturbed surface sediment mechanically with a hoe pick to release Hg0 adsorbed in soils and vegetation. Measuring gaseous mercury using a portable device is simple, effective, and more efficient than standard geochemical surveys that collect sediment, soils, and vegetation. The method will become increasingly useful to the mineral industry as exploration shifts into areas covered by overburden.
The Value of Scientific Machine Learning for Geothermal Applications
Authors: Degen Denise , Cacace Mauro , Moulaeifard s.Mohammad , Wellmann Florian
Published: March 2022

For geothermal applications, we aim to obtain an understanding of the physical processes in the subsurface, to predict the geothermal potential reliable. Naturally, the reliability of the prediction of the physical processes directly relates to the reliability of the evaluation of the geothermal potential. Unfortunately, predicting the physical processes reliable is a non-trivial task because of high uncertainties related to these processes. These uncertainties may arise, for instance, from uncertainties of the rock properties (e.g. thermal conductivity, permeability), structural uncertainties, and not considered physical processes.

Considering the various sources of uncertainties yields a high-dimensional and therefore computationally extremely demanding problem that is not solvable even with state-of-the-art high-performance software packages. To address this curse of dimensionality, we employ a methodology, namely the non-intrusive RB method, combining advanced mathematical algorithms and machine learning methods. This method aims to significantly reduce the dimensionality of the problem while maintaining the physical principles. In contrast to other machine learning methods, the method produces interpretable and scalable models, which are crucial to obtain reliable and robust predictions.

In this work, we show how the method constructs surrogate models for coupled geothermal applications, which allow, in turn, the performance of global sensitivity analysis and uncertainty quantifications. Both methods are essential for improving our model understanding. Furthermore, we demonstrate how the method in combination with developments from the field of computer graphics (e.g. NURBS, and subdivision surfaces) can be used to quantify the influence of structural uncertainties on the temperature distribution.
Reconstructing Weddell Sea current variability since the LGM: insights from authigenic and detrital radioisotope analyses of marine sediments.
Authors: Bollen Michael , Jaccard Samuel , Gutjahr Marcus , Müller Juliane , Blaser Patrick
Published: March 2022

Water-mass transformation in the Weddell Sea is responsible for the generation of 50-70% of Antarctic Bottom Water exported to the global deep ocean, with effects for the deep marine sequestration of atmospheric CO2. Uncertainties in the dynamics of this system urgently need to be addressed to assist with modelling the carbon cycle in the southern high latitudes, and identifying whether the Weddell Sea and the Southern Ocean may act as either a carbon source or sink as the global climate shifts.

In this study, we used sequential acid-reductive leaching and total digestion to obtain neodymium (Nd), lead (Pb), and uranium (U) concentrations and isotopic compositions from both the authigenic and the detrital fractions of sediments from a suite of long-cores and surface sediments around the Weddell Sea. Paired isotope analyses were carried out to reconstruct bottom water conditions during deposition, and determine the sedimentary provenance of lithogenic detritus. The combination allows us to observe the relationship between lithogenic and authigenic phases. Authigenic Nd and Pb isotope signatures were interpreted to reflect pore-water compositions, affected by a combination of bottom-water composition, lithology, and element release from sediments into the pore-water and overlying water column. We further assess whether authigenic U may serve as a proxy for bottom-water oxygenation and ocean productivity at our Southern Scotia Sea sites, giving insight to deep-ocean ventilation and bottom-water export rates from the Weddell Sea.

Our results suggest that detrital isotopic records indicate an increase in sediment delivery from the East Antarctic to the northwestern Weddell Sea during the deglacial. We hypothesize that this was the result of a strengthening in the Weddell Gyre or Antarctic Circumpolar Current at this time. Here, we present an updated dataset of new authigenic and detrital measurements from the Weddell Sea investigating this hypothesis, and we unveil new details of the dynamic nature of Weddell Sea circulation and ice-ocean interactions over the last 30 kyr.
Physical manifestations and ecological implications of Arctic Atlantification
Authors: Assmann Karen M. , Ingvaldsen Randi B. , Primicerio Raul , Fossheim Maria , Polyakov Igor V. , Dolgov Andrey V.
Published: March 2022

The Atlantic gateway to the Arctic Ocean is influenced by vigorous inflows of Atlantic Water. Particularly since 2000, the high-latitude impacts of these inflows have strengthened due to climate change driving so-called ‘Atlantification’ - a transition of Arctic waters to a state more closely resembling that of the Atlantic. In this review, we discuss the physical and ecological manifestations of Atlantification in a hotspot region of climate change reaching from the southern Barents Sea to the Eurasian Basin. Atlantification is driven by anomalous Atlantic Water inflows and modulated by local processes. These include reduced atmospheric cooling, which amplifies warming in the southern Barents Sea; reduced freshwater input and stronger influence

of ice import in the northern Barents Sea; and enhanced upper ocean mixing and air–ice–ocean coupling in the Eurasian Basin. Ecosystem responses to Atlantification encompass increased production, northward expansion of boreal species (borealization), an increased importance of the pelagic compartment populated by new species, an increasingly connected food web and a gradual reduction of the ice-associated ecosystem compartment.
Towards creating the first European Atlas of Soil Fauna
Authors: Cortet Jérôme , Tsiafouli Maria , Krogh Paul-Henning , Russel David
Published: March 2022

The protection of soil biodiversity is essential for ensuring soil functioning and provisioning of related ecosystem services, but also the conservation of species per se. For this purpose, it is essential to know what soil organism is where and how it is influenced by environmental, climate and human activities. 

Numerous studies (there are over 1400 published articles) have been elaborated in Europe regarding soil fauna. A data platform to store data on soil fauna already exists and is currently under further development to become a pan-European data warehouse for soil biodiversity (https://www.eudaphobase.eu/). Though, the data stored in this database until now comprises only a small percent of the available data. Hence, it is evident that a compiled dataset providing an overall understanding of the distribution of several taxa across European biomes and under different land use still is missing.

Attempting to fill this gap, we start a new initiative within the framework of the Cost Action EUdaphobase CA18237: the creation of the first European Atlas of Soil Fauna.  We aim to map, summarize and upscale the current knowledge on soil fauna to help in providing support to the scientific community and directions to stakeholders and policymakers. We seek collaboration (data holders and experts) to identify, collect and analyze data of all groups of micro-, meso- and macrofauna in Europe. 

This presentation will focus on the aims of this initiative and the way we plan to collect data and involve people.
Glide-snow avalanche formation: First insights from soil and snow monitoring
Authors: Fees Amelie , van Herwijnen Alec , Lombardo Michael , Schweizer Jürg
Published: March 2022

Glide-snow avalanches release due to a loss of friction at the interface between the snowpack and the ground. As a result, these avalanches can involve large snow volumes and can have a high damage potential. It is hypothesized that glide-snow avalanche release is linked to the presence of liquid water at the snow-soil interface, but the driving physical processes are poorly understood. We therefore monitored soil and snow properties at our Dorfberg field site above Davos, Switzerland. The field site is a south-east facing slope with frequent snow gliding and glide-snow avalanches. Our soil monitoring setup consisted of two parts. First, we installed a grid of 22 combined, water content and temperature sensors just below the soil surface. The grid covered the entire field site to increase the likelihood of avalanche release above a sensor. Second, we installed two vertical sensor profiles in the soil, each measuring matric potential, water content, and temperature at three depths down to -20 cm. These profiles were continued in the snow with water content and temperature sensors at three heights up to 20 cm. This allowed us to detect gradients and the direction of water flow across the snow-soil interface. Initial results from glide-snow avalanche events showed an increase in water content with increasing snow depth in the days preceding the event. In addition, the soil was close to saturation (high matric potential) and the soil temperature across the entire slope was constant and above 0 °C before release. Although more data are required to confirm our findings, these initial data provide a valuable step towards identifying the driving physical processes at the snow-soil interface. This will help to better understand the source of interfacial water and to improve glide-snow avalanche forecasting.
Identification of meteorite particles from AMOS data using the new user-friendly software interface. 
Authors: Havrila Karol , Gritsevich Maria , Tóth Juraj
Published: March 2022

            All-sky camera systems such as the AMOS network, record a large number of fireball events. By using multi-station triangulation method obtain information about trajectory of the body in the description change in altitude and velocity over time. Based on the characteristic of the object trajectory can determine important physical properties as the input mass of the meteoroid or the final mass of meteorites, and thus the probability of the formation and impact of particles on the Earth's surface. For this purpose, we used the method of dimensionless coefficients α (ballistic coefficient) and β (mass loss coefficient), which define the impact of the dynamical and physical properties of meteoroids on the searched input/final masses.

            Large number of recorded fireballs requires automatic data processing and their effective reduction. For this purpose, we have created a program with a user interface that works with data from all-sky fireballs cameras (in our case we focus on data from the Slovak AMOS system), defines the values of α-β coefficients and evaluates the probability of the meteorite formation with specific mass during the flight through the atmosphere. The program gives an interactive settings of physical parameters of the body and thus defines impact on the required values of body input/final masses. This algorithms was created for the purpose of user-friendly processing of scientific data, and the same time serves for the selecting suitable candidates for the formation and impact of dust particles and meteorites on the Earth's surface.
Convection-resolving climate simulation of the tropical-to-subtropical Atlantic
Authors: Heim Christoph , Schär Christoph
Published: March 2022

Even though the complexity and resolution of global climate models has increased over the last decades, the inter-model spread in equilibrium climate sensitivity has not narrowed. The representation of tropical and subtropical marine clouds remains a major source of uncertainty in climate models. Going to higher model resolution to explicitly resolve a larger fraction of the underlying convective circulations is the most direct way towards reducing the uncertainty associated with these clouds. Convection-resolving models (CRMs) are therefore an attractive complementary tool to study tropical cloud feedbacks. Even though decade-long global CRM simulations are not yet computationally feasible, CRMs can be used in climate applications for selected limited-area domains and periods.

Here we run 3-year-long CRM simulations with the COSMO model over the tropical-to-subtropical Atlantic. We run a control simulation to evaluate the model’s capability of representing the clouds and the radiative balance. We also run a climate change scenario simulation using the pseudo-global warming (PGW) approach to study cloud-radiative feedbacks at convection-resolving resolution.

We find a good agreement between the simulated and observed annual cycle in the top-of-the-atmosphere radiative fluxes, despite a mean bias that should be possible to reduce through model calibration. There are pronounced improvements in the CRM simulation compared to the CMIP6 models over the ITCZ and the trade-wind cumulus region, while the representation of stratocumulus clouds remains challenging also in the CRM simulation. The simulated cloud-radiative feedback is at the upper end of what the CMIP6 models predict due to a pronounced positive longwave feedback at the ITCZ caused by an increase in high clouds. The shortwave cloud-radiative feedback is moderately positive and lies well within the range of the CMIP6 models with a reduction in the low-level cloud fraction over the subtropics and a partly compensating increase in the cloud fraction at the ITCZ.
Predictability of Rossby wave packets in the midlatitudes
Authors: Prestel-Kupferer Isabelle , Schmidt Sören , Riemer Michael , Teubler Franziska
Published: March 2022

Rossby Wave Packets (RWPs) are linked to extreme weather events and exert a strong influence on the predictability of weather systems in the midlatitudes. Considering the whole wave packet, in the sense of the packet envelope, RWPs can be viewed as entities that describe variability of the atmosphere beyond the synoptic scale.

We here examine the predictability of RWPs as such entities. As a skill metric we used the so-called Displacement and Amplitude Score (DAS) applied to the envelope field of the midlatitude flow. The DAS is based on a field deforming method and, as one of its major advantages, avoids the “double-penalty” verification problem without the need to identify single RWP-objects. Object-based methods tend to be highly sensitive to the choice of thresholds used to identify the objects and conceptual issues arise when assigning forecast to analysis objects. We assess RWP predictability using NOAA GEFSV12 ensemble reforecasts for RWPs that have been previously tracked in ERA5 data, due to the higher available temporal resolution.

A prominent result is that RWP predictability depends on the stage of the RWP lifecycle: The propagation stage exhibits higher predictability than the decay or genesis stage. A small seasonal dependence is found, with summer being the least predicable season. No significant dependence is found on size and amplitude of RWPs or their geographical location. The presentation will further discuss the link of RWP predictability to different MJO-Phases as one means to better understand the role of the MJO in midlatitude predictability.
Importance of landfast ice for ice shelves melt rate projection under future climate conditions in the Totten area, East Antarctica
Authors: Van Achter Guillian , Fichefet Thierry , Goosse Hugues
Published: March 2022

The Totten Glacier in East Antarctica is of major climate interest because of the large fluctuation of its grounding line and of its potential vulnerability to climate change. The Totten ice shelf melt rate is predicted to increase under future climate conditions, but this increase may differ on whether the landfast ice is represented in the model or not. Using a series of high-resolution, regional NEMO-LIM-based experiments, including an explicit treatment of ocean – ice shelf interactions and a landfast ice representation, we simulate the ocean – ice interactions in the Totten Glacier area for both historical (1995-2014) and future (end of the 21 st following RCP 4.5) periods. We show major changes between historical and projection runs as increased ice shelf melt rate, loss in sea ice production or intensified ocean circulation. Moreover, the representation of landfast ice dampens the ice shelf melt rate increase. The Totten ice shelf melt rate is increased between the two periods by either +41% when landfast ice is taken into account, or by 58% when it is not taken into account. This highlights the importance of including a landfast ice representation in our ocean models in order to predict realistic ice shelf melt rate increase in East Antarctica.
Seasonal dynamics and toxicity of PM-bound PAHs in northernmost European megacity.
Authors: Chichaeva Marina , Zavgorodnyaya Yuliya , Popovicheva Olga , Semenova Arina , Kasimov Nikolai
Published: March 2022

Cities are prone to air pollution caused by emissions associated with population activities such as road transport, industry, heating, and residential sector. The concentration and chemical composition of particulate matter (PM) is of particular importance as the parameter of air quality measurements. Concerning impact on urban air quality and hazardous health effects accompanied by the capacity for long-range atmospheric transport, polyromantic hydrocarbons (PAHs) are numbered among priority pollutants in the national and international regulatory activities. Seasonal dynamics and toxicity of PM-bound PAHs in a northern context attract the particular attention.

Sampling and PM10-bound PAHs characterization were carried out in urban background of Moscow megacity, the largest as well as the northernmost megacity in Europe. Composition of 16 PAHs which are numbered in the EPA list of ‘Priority Pollutants’, were considered for three periods: spring (from mid-April to the end of May, when a positive average daily temperature is set in Moscow), autumn (from the end of September to the end of November), and winter (from early December to mid-January, when the average daily temperature reliably drops below zero). The sum of 16 PAHs had ranged over the observation period from 0.4 to 10 ng/m3, with increase of the median concentration from spring and autumn to winter due to the maximum anticyclonic atmospheric circulation and emissions from thermal power plants in winter as well as the transition of PAH from PM to the gas phase with an increase of the temperature in spring. Average PAH toxic equivalent (TEQs) were higher in winter and autumn than those in summer and spring. Increased concentrations for BaA, BaP,BgP, Cry, BbF due to high wind speeds indicate a distant source and a long-range transfer of pollutants. While the presence of maxima of concentrations at medium or low wind speeds can serve as an indication of the proximity of sources, as well as the weakening of atmospheric circulation, which leads to accumulation of pollutants (ANT, PYR, BbF, DiBaA, BLU, PHE, BkF) in the measurement area.

Based on the statistical processing, high (> 0.75) positive correlations for all individual PAHs were obtained in autumn and winter. This indicates the high stability and the absence of significant transformation of PAH due to physical and photochemical reactions. At higher temperature in spring compared to autumn-winter, low correlations for phenanthrene was observed due to evaporation of the lowest molecular weight PAHs could proceed more intensively on the aerosol surface.

This work is supported by the Russian Government, through its grant number 14.W03.31.0002.

 

 
Gallium and germanium in metallurgical slags: mineralogy and potential recovery
Authors: Ettler Vojtech , Mihaljevic Martin , Jedlicka Radim , Kribek Bohdan , Mapani Ben , Kamona Fred , Bowell Rob J. , Hrstka Tomas
Published: March 2022

Gallium (Ga) and germanium (Ge) are technologically essential critical elements. This study focuses on old metallurgical slags generated by processing non-ferrous metallic ores in Tsumeb, northern Namibia, containing interestingly high concentrations of these elements (up to 156 ppm Ga and 441 ppm Ge). Mineralogical investigation indicated that the slags were composed of olivine-, melilite- and spinel-group phases, metal(loid)-rich glass, and sulfide/metallic inclusions. The FEG-EPMA and LA-ICP-MS data confirmed that major carriers of Ga were Zn-Fe-Al spinels (up to 1370 ppm), and Ge was primarily bound in a glassy phase (up to 470 ppm), especially in the case of granulated slags. The abiotic extraction tests, simulating a hydrometallurgical recovery via agitation leaching, were carried out in sulfuric, nitric, and hydrochloric acids (pH = 0.2-0.3, 25 °C and 70 °C, pulp density of 1%) to determine the release of Ga and Ge from slags. Their leaching attained a steady state after 6 hours for granulated slags and 2 hours for finely ground slags. The extractability of both Ga and Ge was slightly higher for the high-temperature trials. The overall recovery was the best for the sulfuric acid extractions and attained 100% and 96% for Ga and Ge, respectively. Our investigation indicates that understanding the specific binding of critical elements is crucial for their potential recovery from slags. This study was supported by the Czech Science Foundation project (GAČR 19-18513S).
High-resolution global water quality assessment using globally available open data and the BlueEarth Digital Environment
Authors: Hegnauer Mark , Troost Tineke , Liguori Christian , van den Roovaart Joost , Boisgontier Helene , van Gils Jos , Altena Wilfred , Wardani Ira
Published: March 2022

Anthropogenic contaminants are a growing issue of concern. So far, over 350,000 chemicals and mixtures of chemicals have been registered for production and use (Wang et al., 2020), and numbers are ever increasing. As a result of their use, many of these chemicals find their way to freshwater systems (e.g., Stroomberg et al., 2018) and coastal waters (e.g., UNESCO and HELCOM, 2017).

In the EU-project SOLUTIONS, tools and methods have been developed to answer the question to what extent the full plethora of man-made chemicals is likely to negatively affect the ecological status of surface waters and ground waters, or the drinking water production (Van Gils et al, 2020).

For the United Nations we are applying one of these methods at a global scale in the World Water Quality Assessment (WWQA), combining a high-resolution hydrological model (Wflow SBM: https://github.com/Deltares/Wflow.jl) with the modules on emissions (D-Emissions) and water quality (D-WaterQuality). The models are setup using the open-source package hydromt (https://deltares.github.io/hydromt/latest/), which is developed under the umbrella of the BlueEarth Digital Environment (https://blueearth.deltares.org/).

The expected outcome is an approximative global assessment of the water quality status due to toxic stress. SOLUTIONS model results are used to correlate toxic stress to socio-economic indicators, for the current situation and for several relevant future climate and socio-economic scenarios. The selected indicator, msPAF, is a measure of the acute toxic effect of exposure to a near real-world chemical mixture, in relation to the regulatory concept of ecological impact magnitudes (species loss), as utilized to classify ecological impacts under the Water Framework Directive (Posthuma et al., 2019).
An unambiguous global map projection for the Kuiper belt object Arrokoth by fitting a Quincuncial Adaptive Closed Kohonen (QuACK) map
Authors: Grieger Björn
Published: March 2022

On the 1st of January 2019, the New Horizons space probe flew by the Kuiper belt object Arrokoth. Images revealed a bilobate shape that would not allow any common map projection to display the complete surface, because multiple points have the same longitude and latitude. Arrokoth shares this feature with 67P/Churyumov-Gerasimenko, the target comet of the Rosetta mission. In order to map the complete surface of the comet, a Quincuncial Adaptive Closed Kohonen (QuACK) map has been fitted to 67P by Grieger (2019). Here, we fit a QuACK map similarly to the shape model of Arrokoth by Stern et al. (2019) and project some of the closest images acquired by the LORRI instrument onto it.
The Impact of Hengduan Mountains Formation on the Regional Monsoon Climate and Extreme Precipitation
Authors: Xiang Ruolan , Steger Christian , Sørland Silje , Schär Christoph
Published: March 2022

The Hengudan Mountains, located at the south-eastern fringe of the Tibetan Plateau, reveal exceptionally high biodiversity. It is believed that this feature is linked to past complex interactions between climate, land surface dynamics and plate tectonics in this region. Contemporary topography was formed by plate tectonics, causing surface uplift, and spatially heterogeneous erosion, which shaped the deep river valleys. The non-hydrostatic regional climate model COSMO is applied to study the impact of surface uplift and river incision. Decades-long simulations at horizontal resolutions of 12 and 4.4 km grid spacing are performed. To study the impact of local topography on climate, we consider two idealized experiments with terrains deviating from the present-day topography: In the first experiment, we reduce the topography in a spatially non-uniform way. This altered topography reflects a past potential state of the Hengduan Mountains. In the second experiment, we remove the deep valleys by applying an envelope topography to quantify the effects of deep valleys on the local climate. Both experiments assume that that the large-scale (continental) climate did not change, i.e., the experiments are driven by large-scale reanalysis data. Preliminary results from the coarse-resolution 12 km COSMO simulation indicate that the uplift of the Hengduan Mountains has a strong impact on the summer monsoon over South Asia caused by circulation changes around the uplifted region. The uplift of the Hengduan Mountains strengthens the westerly wind anomalies from the ocean in South Asia and markedly intensifies the precipitation in Indochina and southwestern China. Besides, the cyclonic circulation in the Bay of Bengal extends eastward, indicating an intensification of the East Asian summer monsoon. The diabatic heating in the eastern Tibetan Plateau increases in response to the regional uplift and it is coupled with the increased precipitation in summer through moist processes. On the contrary, the uplift has little impact on the strengthening of the winter monsoon. In the next stage, we will conduct the same simulations at a higher horizontal resolution of 4.4 km, which captures local terrain more accurate. These simulations will use explicit rather than parameterized convection, thereby providing more realistic estimates of heavy precipitation and erosion. Subsequently, we will run the same experiments for the envelop topography. We expect to relate the changes in the frequency and intensity of extreme precipitation to the changes in the local moisture transport and vertical movement in the high-resolution perspective. In the future, the two different topographies along with the modern topography will be used for simulations of two time periods in the past (i.e., the Last Glacial Maximum (21,000 years ago) and a phase in the Late Miocene (∼7 Ma)) and the future climate (2070–2100).
Statistical properties of extreme wave groups based on field data
Authors: Fu Ruili , Zheng Jinhai , Tao Aifeng , Wang Gang
Published: March 2022

An extreme wave always evolves from a wave group in random wave trains. Therefore, better insights into extreme wave groups are crucial for the safety design of marine structures. In the present work, the marginal and bivariate distributions of extreme wave group energy and duration are investigated based on the field datasets from Norway's North Sea. The most probable extreme wave group energy and duration can be obtained based on the distributions, then evolutions of wave shapes of extreme wave groups are investigated and compared with the present extreme wave group theories. It is found that the wave shapes are asymmetry with time-spatial evolution.