bluuebunny/crossref_metadata_2025 huggingface dataset:
Personal Initiative, Social Networking and Entrepreneurial Inclination among Disabled Students of Tertiary Institutions in Plateau State
Authors: Isaac Palang Agbok , Dakung Reuel Johnmark , Auta Habila Dogo
Published: March 2022

Entrepreneurship is vital in the areas of innovation, job creation, nations ‘economic and societal advancement. In view of that, Social networking is seen to be important in moderating the relationship between personal initiative and entrepreneurial inclination. This study focuses on investigating the moderating role of social networking on personal initiative and entrepreneurial inclination relationship of disabled students. The study followed a descriptive survey where quantitative approach was employed. Out of the total number of (210) questionnaires administered to disabled students across the five Tertiary Institutions (University of Jos, Plateau State Polytechnic, Plateau State University, College of Education Gindiri and Federal college of Education Pankshin) in Plateau State, Nigeria, two hundred and seven (207) were retrieved but only two hundred and three (203) were used for analysis after eliminating wrongly filled questionnaires by the respondents and the unit of analysis was at the individual level. Analysis of data involved the use of statistical package for Social Sciences SPSS version 23.0 and AMOS version 23. Hypotheses were tested using structural equation model. Results revealed that personal initiative (proactiveness, resilience and innovation) significantly and positively influences entrepreneurial inclination. Also, social networking does not moderate (Weakens) the relationship between personal initiative and entrepreneurial inclination of disabled students of Tertiary Institutions in Plateau State. The present study will help policy makers and government to give special attention to disabled students by encouraging innovativeness and proactiveness among them thereby boosting their entrepreneurial spirit. Also, the society should help encourage and support the disabled students through positive interaction and networking to help boost their entrepreneurial inclination. Like any other research, this study is limited in the following ways. Since only a single research methodological approach was employed, future research could undertake a mixed approach and triangulate to validate the current findings. Further, a longitudinal approach should be employed to study entrepreneurial inclination trends among disabled students over years.
Stratigraphic record of Eponides Montfort 1808 (benthic Foraminifera) through the Paleocene carbonates of the northern Neotethys margin
Authors: Consorti Lorenzo , Schlagintweit Felix , Koroglu Fatih , Rashidi Koorosh
Published: March 2022

In the former northern Neotethys margin where Paleocene shallow-water limestone successions crop out (Austria, Turkey and Iran), morphotypes closely resembling Eponides have been recognized. These foraminifers are lamellar-perforated, with a trochospirally arranged set of trapezoidal chambers.We have tested their generic identification through a detailed architectural analysis of thin sections of carbonate rocks in which Eponides-like specimens have abundantly been recovered. This study shows the occurrence of bipartitor, arched septa and a pseudoumbilicus formed by the fusion of ventral ends of chambers. These features allow us to identify the specimens as Eponides, although the specific attribution has not been attempted. The evolutionary pattern displayed by the Late Cretaceous and Cenozoic Eponides and phylogenetically-related allies is briefly discussed.
Making Hip Hop Theatre
Authors: Beswick Katie , Murray Conrad
Published: March 2022

Making Hip Hop Theatre is the essential, practical guide to making hip-hop theatre. It features detailed techniques and exercises that can guide creatives from workshops through to staging a performance. If you were inspired by Hamilton, Barber Shop Chronicles, Misty, Black Men Walking or Frankenstein: How to Make a Monster, this is the book for you.

Covering vocal technique, use of equipment, mixing, looping, sampling, working with venues and dealing with creative challenges, this book is a bible for both new and experienced artists alike. Additionally, with links to online video material demonstrating and elaborating on the exercises included, it offers countless useful tools for teachers and facilitators of drama, music and other creative arts.

Alongside this practical guidance is an overview of hip hop history, giving theoretical and historical context for the practice. From documentation of Conrad Murray’s major productions, to commentary from leading practitioners including Lakeisha Lynch-Stevens, David Jubb, Emma Rice, Tobi Kyeremateng and Paula Varjack, readers are treated to a detailed insight into the background of hip hop theatre.

Edited by scholar Katie Beswick and genre pioneer Conrad Murray, Making Hip Hop Theatre is a vital teaching tool and provides a much-needed account of a burgeoning aspect of contemporary theatre culture.
A People Betrayed
Authors: Melvern Linda
Published: March 2022

Events in Rwanda in 1994 mark a landmark in the history of modern genocide. Up to one million people were killed in a planned public and political campaign. In the face of indisputable evidence, the UN Security Council failed miserably in its response.

In this classic of investigative journalism, Linda Melvern tells the compelling story of what really happened, revealing both the scale, speed and intensity of the unfolding genocide, as well as exposing the governments and individuals who could have prevented what was happening, if they had chosen to act. The book also tells the unrecognised heroism of those who stayed on during the genocide - from volunteer peacekeepers to courageous NGO workers.

Twenty-five years on from one of the darkest episodes in modern history, A People Betrayed is a shocking indictment of how Rwanda was ignored then and how today it is remembered in the West.
The Vigilante Thriller
Authors: Edwards Cary
Published: March 2022

This is a detailed examination of vigilantism in 1970s American film, from its humble niche beginnings as a response to relaxing censorship laws to its growth into a unique subgenre of its own. Cary Edwards explores the contextual factors leading to this new cycle of films ranging from Joe (1970) and The French Connection (1971) to Dirty Harry (1971) and Taxi Driver (1976), all of which have been challenged by contemporary critics for their gratuitous, copycat-inspiring violence. Yet close analysis of these films reveals a recurring focus on the emerging moral panic of the 1970s, a problematisation of Law and Order's role in contemporary society, and an increasing awareness of the impossibility of American myths of identity.
Build Automation Tools for Software Development
Authors: Prakash Mridula
Published: March 2022

The automated processes will play an increasingly vital role in continuous integration as the pace of design and development of new software picks up. With the importance of software build automation tools taking center stage, the present paper undertakes a comparative analysis of three best available solutions - Maven, Gradle and Bazel. We aim to evaluate the solutions based on their efficiency and performance in the context of software build automation and deployment. There are some fundamental differences in the way each tools approach builds. The aim of this study is also to provide the reader with a complete overview of the selected build automation tools and, the relevant features and capabilities of interest. In addition, the paper leads to a broader view on the future of the build automation tools ecosystem.
SSL/TLS Encrypted Traffic Application Layer Protocol and Service Classification
Authors: Li Kunhao , Lang Bo , Liu Hongyu , Chen Shaojie
Published: March 2022

Network traffic protocols and service classification are the foundations of network quality of service (QoS) and security technologies, which have attracted increasing attention in recent years. At present, encryption technologies, such as SSL/TLS, are widely used in network transmission, so traditional traffic classification technologies cannot analyze encrypted packet payload. This paper first proposes a two-level application layer protocol classification model that combines packets and sessions information to address this problem. The first level extracts packet features, such as entropy and randomness of ciphertext, and then classifies the protocol. The second level regards the session as a unit and determines the final classification results by voting on the results of the first level. Many application layer protocols only correspond to one specific service, but HTTPS is used for many services. For the HTTPS service classification problem, we combine session features and packet features and establish a service identification model based on CNN-LSTM. We construct a dataset in a laboratory environment. The experimental results show that the proposed method achieves 99.679% and 96.27% accuracy in SSL/TLS application layer protocol classification and HTTPS service classification, respectively. Thus, the service classification model performs better than other existing methods.
STEM PROJECT — TOOL FOR THE FORMATION OF COMPETENCIES OF APPLICANTS FOR EDUCATION
Authors: Patrykeieva O. O. , Chernomorets V. V. , Vasylenko I. V. , Kovalenko M. V.
Published: March 2022

The article attempts to define the concepts: “STEM-project” and “project with elements of STEM”. It is proposed to interpret the concept of “project with elements of STEM” as a set of practical forms and methods that effectively form the key competencies needed by each person for successful life, personality development, motivation to learn, creative thinking, research skills, ability to self-study through implementation competence approach during the implementation of STEM-projects. The necessity of implementation of project-research activity with STEM elements is substantiated not only at mastering of subjects of a natural-mathematical cycle, but also at mastering of all school courses that is quite real considering high level of integration of knowledge and skills of pupils in modern conditions. The introduction of STEM-projects in educational institutions determines the self-determination of young people, the effective solution of problems and tasks of career guidance work. The project activity is one of the most promising components of the educational process, which creates conditions for creative self-development and self-realization of students, forms all the necessary life competencies: multicultural, speech, information, political and social. The independent search for knowledge, their systematization, the ability to navigate in the information space, see the problem and make decisions is through the method of projects — effective learning technology. The relevance of the article is due to the need to expand the scientific and conceptual apparatus of STEM-education, providing practical advice on the implementation of forms, methods and techniques of STEM training in the general educational process.
Pollen observations at four EARLINET stations during the ACTRIS-COVID-19 campaign
Authors: Shang Xiaoxia , Baars Holger , Stachlewska Iwona S. , Mattis Ina , Komppula Mika
Published: March 2022

Abstract. Lidar observations were analysed to characterize
atmospheric pollen at four EARLINET (European Aerosol Research Lidar
Network) stations (Hohenpeißenberg, Germany; Kuopio, Finland; Leipzig,
Germany; and Warsaw, Poland) during the ACTRIS (Aerosol, Clouds and Trace
Gases Research Infrastructure) COVID-19 campaign in May 2020. The
reanalysis (fully quality-assured) lidar data products, after the
centralized and automatic data processing with the Single Calculus Chain
(SCC), were used in this study, focusing on particle backscatter
coefficients at 355 and 532 nm and particle linear depolarization ratios (PDRs) at 532 nm. A novel method for the characterization of the pure pollen
depolarization ratio was presented, based on the non-linear least square
regression fitting using lidar-derived backscatter-related Ångström
exponents (BAEs) and PDRs. Under the assumption that the BAE between 355 and
532 nm should be zero (±0.5) for pure pollen, the pollen
depolarization ratios were estimated: for Kuopio and Warsaw stations, the
pollen depolarization ratios at 532 nm were of 0.24 (0.19–0.28) during the
birch-dominant pollen periods, whereas for Hohenpeißenberg and
Leipzig stations, the pollen depolarization ratios of 0.21 (0.15–0.27) and 0.20 (0.15–0.25) were observed for periods of mixture of birch and grass
pollen. The method was also applied for the aerosol classification, using
two case examples from the campaign periods; the different pollen types (or
pollen mixtures) were identified at Warsaw station, and dust and pollen were
classified at Hohenpeißenberg station.
Five-satellite-sensor study of the rapid decline of wildfire smoke in the stratosphere
Authors: Martinsson Bengt G. , Friberg Johan , Sandvik Oscar S. , Sporre Moa K.
Published: March 2022

Abstract. Smoke from western North American wildfires reached the stratosphere in
large amounts in August 2017. Limb-oriented satellite-based sensors are
commonly used for studies of wildfire aerosol injected into the stratosphere
(OMPS-LP (Ozone Mapping and Profiler Suite Limb Profiler) and SAGE III/ISS
(Stratospheric Aerosol and Gas Experiment III on the International Space
Station)). We find that these methods are inadequate for studies of the first 1–2 months after such a strong fire event due to event termination
(“saturation”). The nadir-viewing lidar CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) is less affected due to shorter path in the smoke; furthermore, it provides a means to develop a method to
correct for strong attenuation of the signal. After the initial phase, the
aerosol optical depth (AOD) from OMPS-LP and CALIOP show very good agreement
above the 380 K isentrope, whereas OMPS-LP tends to produce higher AOD
than CALIOP in the lowermost stratosphere (LMS), probably due to reduced
sensitivity at altitudes below 17 km. Time series from CALIOP of
attenuation-corrected stratospheric AOD of wildfire smoke show an
exponential decline during the first month after the fire, which coincides
with highly significant changes in the wildfire aerosol optical properties.
The AOD decline is verified by the evolution of the smoke layer composition,
comparing the aerosol scattering ratio (CALIOP) to the water vapor
concentration from MLS (Microwave Limb Sounder). Initially the stratospheric
wildfire smoke AOD is comparable with the most important volcanic eruptions
during the last 25 years. Wildfire aerosol declines much faster, 80 %–90 % of the AOD is removed with a half-life of approximately 10 d. We
hypothesize that this dramatic decline is caused by photolytic loss. This
process is rarely observed in the atmosphere. However, in the stratosphere
this process can be studied with practically no influence from wet
deposition, in contrast to the troposphere where this is the main removal
path of submicron aerosol particles. Despite the loss, the aerosol
particles from wildfire smoke in the stratosphere are relevant for the
climate.
Aerosol Optical Properties of Extreme Global Wildfires and Estimated Radiative Forcing with GCOM-C SGLI
Authors: Tanada Kazuhisa , Murakami Hiroshi , Hayasaka Tadahiro , Yoshida Mayumi
Published: March 2022

Abstract. Wildfires damage land ecosystems and significantly impact the atmosphere by releasing large amounts of CO2 and aerosols. Aerosols, in particular, have a radiative forcing potential that perturbs the global radiation balance. Therefore, understanding their optical properties is essential to estimate the radiative forcing for predicting the climatic impact due to burning. The Global Change Observation Mission—Climate, or GCOM-C (SHIKISAI), is a polar-orbit satellite launched by JAXA on 23 December 2017. This study analyzed wildfires in the Amazon, Angola, Australia, California, Siberia, and Southeast Asia that occurred after 2018 using data from the GCOM-C satellite obtained with the Second-generation Global Imager (SGLI), a multi-band optical imaging radiometer. We compared the aerosol optical properties of Ångström Exponent (AE) and Single Scattering Albedo (SSA) and found that their distributions are different for each region. In addition, the negative correlations are found in the Amazon, Angola, Siberia, and Southeast Asia when we locally fitted the AE and SSA relationship for each wildfire by a linear function. This is likely due to the effect of hygroscopic growth (SSA becomes larger with water uptake), considering the difference in relative humidity in the six regions, and the significant behavior of the aerosol aging. We also found that the relationship between SSA and relative humidity varies depending on the type of the burned vegetation. For the needle-forest-dominated group, a higher SSA is observed in the range from 40 % to 70 % of relative humidity than the broad forest-dominated group. This global investigation of the aerosol optical properties reveals that their characteristics differ due to regional differences such as relative humidity and vegetation type. Thus, the regional characteristics and the aging effect of biomass-burning aerosols must be considered in model predicting. Moreover, we estimated the net incoming radiation at the top of the atmosphere during the intense fire periods to understand the impact of the direct effect of biomass burning aerosols on radiative forcing. The estimates show a significant negative radiative forcing (i.e., a cooling effect) over the ocean (−78 and −96 Wm−2 in Australia and California, respectively). In contrast, small values are observed over land (∼ −10 Wm−2 for all six regions). This suggests that the radiative forcing depends on the region of the wildfire plumes. Therefore, taking the regional characteristics of the optical property and surface reflectance into account is necessary to estimate the effect on radiative forcing and future impacts of a short-lived climate forcer from wildfires.
Characteristics of reservoirs to mitigate drought effects with a hedging rule triggered by drought limited water level 
Authors: Luo Chengxin , Ding Wei , Xu Bo , Zhang Chi
Published: March 2022

Severe droughts are challenging the development of society and economy worldwide. Whilst hedging rules for reservoir operations contribute to reduce the risk of unacceptably severe water shortage during droughts, they could be of trivial value for some reservoir water supply systems considering water supply reliability, vulnerability and resilience. There is still no consensus on the quantitative characteristics of water system hedging rules should be applied to. In this work, reservoir water level named as drought limited water level(DLWL) is employed to trigger practical zone-based water supply rule firstly. Then the impact of DLWL on the water supply performance is analyzed with a range of hypothetical reservoir water supply systems. Based on it, characteristics of reservoirs which DLWL should not be applied to is identified using scenario discovery. For these reservoirs, main influencing factors are revealed and effective drought management measures to ensure reliable water supply are proposed accordingly. For the rest reservoirs that DLWL should be applied to, a multi-objective DLWL optimization method is proposed and applied to Qing Reservoir, a typical water supply reservoir in Northern China. The influence of changing environment on DLWL is studied with a comprehensive sample of deeply uncertain factors. Results show that hedging policy triggered by DLWL has a remarkable advantage over the standard operation rules to mitigate effect of drought. To adapt to increasing water supply pressure featured with increasing demand, decreasing streamflow volume and more variable streamflow, DLWLs during high water demand period ought to be raised and DLWLs during dry season ought to be reduced. Insights from this work have general merit for taking the most effective measures to relieve water shortage and regulate existing hedging rules to adapt to changing environment.
A study of iodine concentration in soils and drinking waters of the Mountainous Crimea
Authors: Berezkin Victor , Glebov Victor , Kayukova Elena
Published: March 2022

Iodine deficiency is the most common cause of endemic goiter and other diseases, largely due to the geographical features of the regions. Iodine deficiency diseases can occur not only in inland regions and high-altitude areas, but also in those regions where iodine is poorly involved in the food chains of the local population. Thus, for some territories, an important factor of iodine deficiency may be the diversity of rocks and the difference in soils and aquifers caused by them.

The purpose of the article is to identify the contrast in the concentration of iodine content in the soil cover and natural drinking waters in the Mountainous Crimea, on different rocks. Soil and water samples collected in several regions of the Mountainous Crimea, mostly in Bakhchisarai, were examined.

Samples of natural drinking water (n=34) were taken in three districts of the Mountainous Crimea (Bakhchisarai, Alushta and Simferopol) from various sources (rivers, wells, ponds, aqueduct) in 2017. Soil samples (n=23) were taken in the Bodrak River valley (Bakhchisarai district) from the upper horizons (sampling depth up to 20 cm) in 2019. Iodine was determined by kinetic thiocyanate-nitrite method in the laboratory of the Institute of Geochemistry of the Russian Academy of Sciences.

The iodine content in the surveyed drinking water sources corresponds to the existing standards (2-10 μg/l), however, for some sources, extremely low values of iodine content are observed (both for wells 0.89 μg/l and for private pumps and aqueduct 1.11 μg/L), which can be determined primarily by the composition of the water-bearing rocks. The highest median values are marked for springs (Me=5.34 μg/L; n=8) and rivers (Me=6.77 μg/L; n=8), the lowest for aqueduct (Me=1.74 μg/L; n=7). The high variability of iodine in the soils of the automorphic landscapes of the Crimean Mountains was established from 0.43 mg/kg (mountain cambisols) to 15.4 mg/kg (regosols), depending on the humus content and the pH. The highest median values are marked for regosols (Me=5.6 mg/kg; n=13) and cambisols (Me=1.7 mg/kg; n=6), the lowest for fluvisols (Me=1.1 mg/kg; n=4).

The dependence of the iodine content in the upper horizons of different types of soils, primarily on the content of humus and soil pH-water, has been established. It has been confirmed that the content of iodine in natural waters is primarily determined by the difference in aquifers. The study was carried out without financial support, with the partial support of the Laboratory of Biogeochemistry of the Russian Academy of Sciences, which provided equipment for measuring iodine.
Mn/Mg ratios of arc lavas show that early garnet fractionation occurs near the Moho of thick continental arcs
Authors: Klein Benjamin , Müntener Othmar
Published: March 2022

The fractionation of garnet from arc magmas is hypothesized to play an important role in a wide range of geologic processes including the formation of continental crust, the oxidation of arc magmas and the development of porphyry copper deposits. However, garnet is only stable in mafic to intermediate hydrous arc magmas at pressures of at least 0.8-1 GPa and is extremely rare in erupted arc magmas. It is therefore difficult to directly document and study garnet fractionation in the field. Instead, garnet fractionation is frequently inferred based on trace element proxies such as La/Yb, Dy/Yb and Sr/Y. As garnet stability is strongly pressure sensitive, these ratios are also commonly used as proxies for fractionation pressure and crustal thickness. However, this approach is problematic as these ratios span a wide range of values in primary mantle melts independent of crustal thickness, and can also be modified within the crust by amphibole fractionation and plagioclase accumulation.

We show here that Mn/Mg ratios provide an attractive alternative method for inferring garnet fractionation in erupted lavas. Primary mantle melts have highly restricted Mn/Mg ratios that are consistent with melt in equilibrium with mantle olivine. Therefore, this ratio does not appear to keep a record of subducted slab contributions, unlike most trace element proxies. Using a large compilation of experimental data and new high-precision analyses of Mn partitioning in existing garnet-bearing experiments, we show that all common cumulate silicate phases except garnet have Mn/Mg KD values below 0.5, while the garnet KD is greater than 1, and thus garnet fractionation produces derivative magmas with distinctly lower Mn/Mg ratios.  Using the compiled experimental data, we parameterized an empirical model of Mn partitioning in garnet as a function of pressure and temperature. This model allows for the rigorous investigation of the role of garnet fractionation at both modern and ancient subduction zones. We find clear evidence for garnet fractionation in most arcs with seismically estimated crustal thicknesses greater than ~45 km. This garnet fractionation signature is observable at relatively unevolved melt compositions (≤54 wt. % SiO2). At these melt compositions garnet is likely only stable at pressures of at least 1.5 GPa, suggesting that garnet fractionation initiates at or below the Moho.
The dynamic Coulomb stress changes caused by remoteearthquakes based on the borehole strainmeter data
Authors: Li Fuzhen , Ren TianXiang , Chi ShunLiang , Zhang Huai , Shi YaoLin
Published: March 2022

Sufficient shreds of evidence have proved the existence of the remote triggering effect of large earthquakes. To understand its mechanism, it is necessary to conduct detailed investigations on the influence of the far-field dynamic stress changes on the stress state of faults. As an important tool of ultra-broadband crustal stress monitoring, a four-component borehole strainmeter can directly record the dynamic changes of horizontal strain and stress caused by seismic waves. These data are of great importance to study the dynamic Coulomb stress changes and related triggering effects, but have not been paid sufficient attention to so far. This paper analyzes the data of the four-component borehole strainmeter at Gaotai and Tonghua stations, which recorded the far-field strain changes of four major earthquake events in the Pacific region in 2018. We successfully identify the seismic phases of P, S, and surface waves, and analyze the characteristics of different phases through the stress petal method. The dynamic stress changes are calculated, demonstrating the feasibility of using borehole strainmeter data to quantitatively study the triggering effect of teleseismic waves of earthquakes with different magnitudes at different epicentral distances. We find that the direction of the principal stress axis of the dynamic stress changes is generally consistent with the azimuth of the earthquake epicenter. We further discuss the Coulomb stress changes on the major faults near the stations. According to the results, the peak values of the dynamic Coulomb stress changes produced by four earthquakes on the fault planes near Gaotai and Tonghua stations are at the magnitude of hundreds of Pa, which are lower than the threshold value of dynamic triggering. This is also consistent with the observation that no dynamically triggered earthquakes are found on the faults. However, the idea and method of this paper provide useful insight into the detection of possible dynamic triggering of large earthquakes.
Sea ice import affects Beaufort Gyre freshwater adjustment
Authors: Cornish Sam , Muilwijk Morven , Scott Jeffery , Marson Juliana , Myers Paul , Zhang Wenhao , Wang Qiang , Kostov Yavor , Johnson Helen
Published: March 2022

The Arctic Ocean's Beaufort Gyre is a wind-driven reservoir of relatively fresh seawater, situated beneath time-mean anticyclonic atmospheric circulation, and is covered by mobile pack ice for most of the year. Liquid freshwater accumulation in and expulsion from this gyre is of critical interest to the climate modelling community, due to its potential to affect the Atlantic meridional overturning circulation (AMOC). In this presentation, we investigate the hypothesis that wind-driven sea ice import to/export from the BG region influences the freshwater content of the gyre and its variability. To test this hypothesis, we use the results of a coordinated climate response function (CRF) experiment with four ice-ocean models, in combination with targeted experiments using a regional setup of the MITgcm, in which we apply angular changes to the wind field. Our results show that, via an effect on the net thermodynamic growth rate, anomalies in sea ice import into the BG affect liquid freshwater adjustment. Specifically, increased ice import increases freshwater retention in the gyre, whereas ice export decreases freshwater in the gyre. Our results demonstrate that uncertainty in the cross-isobaric angle of surface winds, and in the dynamic sea ice response to these winds, has important implications for ice thermodynamics and freshwater. This mechanism may explain some of the observed inter-model spread in simulations of Beaufort Gyre freshwater and its adjustment in response to wind forcing.
Accelerating climate- and weather-forecasts with faster multigrid solvers
Authors: Griffith Matthew , Mueller Eike , Melvin Tom
Published: March 2022

Successful operational weather forecasting with (semi-)implicit timestepping methods relies on obtaining an accurate solution to a very large system of equations in a timely manner. It is therefore crucial that the solver algorithm is fast and efficient, as this can account for up to a third of model runtime.

For models based on mixed finite element discretisations, the standard Schur-complement solver approach is not feasible since the Schur-complement system is dense and cannot be solved with iterative methods. To address this issue in its next-generation forecast model - codenamed LFRic - the Met Office is investigating a so called “hybridised” solver algorithm, which shows its full potential when combined with multigrid techniques.
We introduce both the hybridised discretisation and multigrid techniques on simplified problems, comparing and contrasting these with the current, non-hybridised multigrid solver algorithm used in the Met Office model. We will talk about how this is generalised to the full model and present results from this comparing several solver configurations.
Since our new hybridised multigrid solver reduces the number of global reduction operations, it is particularly promising when solving very large problems on a massively parallel computer. To explore this, we ran our code on large numbers of compute cores, and will present the results of those runs here.
The efficiency of our non-nested multigrid approach depends on the choice of the coarse level finite element space. To further improve the solver algorithm, we compare different coarse level spaces for a simplified setup in the Firedrake finite element code generation framework.
Prospective Changes in Climatology of the CORDEX Domain of Australasia: A Dynamical Downscaling Approach Using RegCM4.6
Authors: Turp M. Tufan , An Nazan , Collu Kamil , Kurnaz M. Levent
Published: March 2022

Although there are increasingly various studies within the frame of CORDEX initiative, most of these studies mainly focus on the domains of Africa, Europe, and the Mediterranean. Therefore, this study presents the regional climate projections for the CORDEX-Australasia domain using RegCM4.6. Projected changes in merely mean temperature and precipitation climatology during the periods of 2011-2040 (near-term), 2041-2070 (mid-term), and 2071-2099 (long-term) with reference to the period of 1971-2000 have been examined for the CORDEX-Australasia domain via regional climate model. Regional climate model runs were employed by using the best parametrizations suggested in the evaluation part of the study. The outputs of two global circulation models (i.e., HadGEM2-ES of the Met Office Hadley Centre, MPI-ESM-MR of the Max Planck Institute for Meteorology) were dynamically downscaled to 50 km under two different Representative Concentration Pathways (RCPs), namely RCP4.5 and RCP8.5. In this respect, seasonal changes in temperature and precipitation climatology of the CORDEX-Australasia domain were analyzed in a higher resolution. The results of the analysis show that there will be increasingly higher temperatures in Australasia towards the end of the century. It is concluded that the mean temperature increase expectation of approximately 1.5-3 ℃ may be around 5 ℃ at the end of the century. On the other hand, the change in precipitation varies greatly depending on the period and sub-region. Average ±20% change in precipitation may occur as 50% or more increases or 30% or more decreases in some places.
Atmospheric phosphorus characterization by 31P-NMR during dust events and bioavailability implications
Authors: Violaki Kalliopi , Panagiotopoulos Christos , Avalos Claudia Esther , Pivetau Laura , Nenes Athanasios
Published: March 2022

Phosphorus is a critical nutrient affecting primary productivity in large areas of oceanic oligotrophic and ultraoligotrophic ecosystems. The principal source of externally supplied inorganic-P in such ecosystems is the atmosphere with dust considered as an important source. However, recent work showed that organic-P originating from bioaerosols and dust can supply as much bioavailable P as inorganic P in dust, and is thus critical for primary productivity. The presence of organic-P in atmospheric samples is typically inferred by subtraction of the amount of inorganic phosphorus from the total amount of phosphorus. At present, there is no direct method for organic-P determination. Direct speciation methods point to important sources (e.g., phospholipids from bioaerosol), but cannot account for the total amount of P in organic from. There is a need therefore to develop a method to directly identify P that are associated with organic compounds. Nuclear magnetic resonance (31P-NMR) spectroscopy can provide such a capability, as it has proven to be a powerful analytical tool for the molecular characterization of organic-P in marine plankton, sinking particles, high molecular weight dissolved organic matter and sediment. The 31P-NMR technique, however, has never been applied to atmospheric samples and is the focus of this study.

Here we analyze Total Suspended atmospheric Particles (TSP) collected during dust events (n=5) in the eastern Mediterranean by using a high-volume air sampler. These particles were then analyzed using magic angle spinning solid-state 31P-NMR. The results showed the typical functional groups in P speciation which were: orthophosphate and monophosphate esters sharing the same chemical shift (H3PO4 and RH2-PO4), phosphate diesters (R1R2 HPO4) and pyrophosphate (H4P2O7). No phosphonates were detected (C-P bond) in TSP samples. Monophosphate esters and diesters are mainly found in nucleotides and their derivatives (e.g., DNA, RNA, AMP, ADP, and ATP), phospholipids and flame retardants (OPEs), and as such they constitute the majority of atmospheric organic-P. The above-mentioned P-organic compounds have C-O-P bonds therefore they are easily hydrolysable in the marine environment by the alkaline phosphatase enzyme providing an important source of P in aquatic ecosystems. Finally, the results showed that the amount of organic-P estimated colorimetrically is about equal to that estimated by 31P NMR indicating that the latter technique can be successfully employed in atmospheric studies for P speciation.
Nonautonomous dynamics and its applications to paleoclimate
Authors: Ghil Michael
Published: March 2022

The dynamics of systems with time-dependent forcing or coefficients has become a matter of considerable interest in the last couple of decades in general and in the last dozen years or so in the climate sciences in particular (Ghil, 2019; Ghil & Lucarini, 2020; Ghil, 2021; Tel et al., 2021; and references therein). We shall provide a general introduction to the topic and illustrate it with several paleoclimate-related examples (Crucifix, 2012; Riechers et al., 2022; Rousseau et al., 2022). Perspectives for further applications of the concepts and methods of the theory of pullback and random attractors and of their tipping points to paleoclimate will also be provided.

References

Crucifix, M.: Oscillators and relaxation phenomena in Pleistocene climate theory, PTRSA, 370, 1140–1165, 2012.

Ghil, M., 2019: A century of nonlinearity in the geosciences, Earth & Space Science, 6, 1007–1042, doi: 1029/2019EA000599.

Ghil, M., 2020: Review article: Hilbert problems for the climate sciences in the 21st century – 20 years later, Nonlin. Processes Geophys., 27, 429–451, https://doi.org/10.5194/npg-27-429-2020.

Ghil, M., and V. Lucarini, 2020: The physics of climate variability and climate change,  Mod. Phys., 92(3), 035002, doi: 10.1103/RevModPhys.92.035002.

Riechers, K., T. Mitsui, N. Boers, and M. Ghil, 2022: Orbital insolation variations, intrinsic climate variability, and Quaternary glaciations, Clim. Past Discuss. [preprint], https://doi.org/10.5194/cp-2021-136, in review.

Rousseau, D.-D., W. Bagnewski, and M. Ghil, 2021: Abrupt climate changes and the astronomical theory: are they related?, Clim. Past, accepted, doi: 10.5194/cp-2021-103 .

Tél, T., Bódai, T., Drótos, G., Haszpra, T., Herein, M., Kaszás, B. and Vincze, M., 2020. The theory of parallel climate realizations. Journal of Statistical Physics, 179(5), 1496–1530.
Efficacy of source-control, use-related and end-of-pipe regulations on river water quality in a large German river catchment: a 50-year trajectory
Authors: Hildebrandt Sophia , Krüger Elisabeth Helen , Westphal Katja , Ruhl Aki Sebastian , Borchardt Dietrich
Published: March 2022

River water quality changes have been shown to follow typical trajectories, often characterized by sequential phases of accelerated degradation, environmental recovery, and responsive management. However, the relationships between anthropogenic mitigation measures such as regulatory interventions and their effects on water quality remain rarely studied and poorly understood.

In this study, we evaluate the effectiveness of three types of regulations: source-control, use-related and end-of-pipe regulations. Using phosphorus (P) as a model substance for water quality, we analyse a 50-year trajectory of measured total phosphorus (TP) concentrations in the river Ruhr, Germany, and link this with a comprehensive analysis of water quality related laws and regulations being enforced at the national and European level over the same time period. We categorized the regulations according to the aforementioned types and re-analysed the infrastructure developments and operation modes in a literature review and based on research in the archives of the responsible river basin management authority.

The strong decline of TP concentrations from a maximum of 0.59mg/l TP in 1977 to around 0.05mg/l TP in the early 21st century resulted dominantly from source control by banning of P in detergents, the parallel construction of wastewater treatment plants and their sequential upgrade to treatment stages incorporating P removal. Thus, while point source pollution decreased, the share of agricultural and other diffuse sources of riverine TP concentrations increased to around 50%, making them the focus of attention nowadays. As source control and end-of-pipe measures have reached a level at which a further reduction of TP concentration in the river through those means would be marginal, use-related measures gain importance, especially for agricultural practices.

Our results show that source-control was the most effective and fastest way of reducing TP pollution, whereas end-of-pipe measures were a necessary, complementary way to reduce P related water quality impairment. Given the current dominance of diffuse pollution sources resulting from agricultural inputs, where the effectiveness of regulation is likely to be limited, additional measures such as awareness, economic incentives and support for agricultural best management practices need to be addressed. These findings may provide important insights into understanding the effectiveness of different regulatory measures, in particular with regard to the increasing introduction of (new) pollutants and associated impacts on the environment and human health.
Impact of debris distribution on glacier morphology: a case study of Panchi Nala Glacier, western Himalaya using field and remote sensing measurements
Authors: Garg Purushottam Kumar , Azam Mohd. Farooq
Published: March 2022

Around 10% of glacier area in the Himalaya is debris-covered with heterogeneous distribution. Debris distribution, as a function of its thickness, induces differential melting and may lead to characteristic slope inversion. The spatial distribution of debris thickness is poorly quantified in the Himalaya with limited field-based measurements. In the present study we conducted a field expedition on the Panchi Nala Glacier (4.50 km2, 60% debris-covered), western Himalaya during September 2021 and measured debris thickness at 73 points using a DGPS. Debris thickness ranges from <1 cm to 50 cm and reaches upto 1 m over extreme margins. In general, the debris is thicker (>25 cm) in the lower reaches (upto 1.5 km from snout) and decreases with increasing distance from snout. This generalization is, however, not always true as some patches of thin debris cover (<3.5 cm) in the lower portion and some patches of thick debris cover (~13 cm) at upper portion were also found. To assess the influence of debris thickness on melting, elevation difference data from Shean et al. (2020) is obtained. The correlation between debris thickness and elevation changes over corresponding pixels is negative (R = −0.58), suggesting that variation in surface elevation changes can partially be explained by the distribution of debris thickness. Spatially, the wastage is comparatively low (−0.69 m/y) around glacier snout where debris cover is thick (~15 cm) and higher (−1.14 m/y) at higher reaches (~3 km from snout) where debris cover is thin (~5 cm). Comparison of profiles derived from SRTM DEM and ASTER DEM along the central flowline for 2000 and 2020, respectively suggests that owing to differential melting, the concavity is developing on the glacier. Thus, debris thickness is playing an important role in regulating the melt and modifying the overall morphology of the Panchi Nala Glacier. 
Modelling of geophysical flows through GPUFLOW
Authors: Bilotta Giuseppe , Ganci Gaetana , Cappello Annalisa
Published: March 2022

Modelling and simulation of geophysical flows are crucial to the forecasting of the propagation extent and the assessment of the related hazards. Here we introduce a new physics-based model called GPUFLOW, which was born from our twenty years of experience in Fluid Dynamics (CFD) modelling of geophysical flows. GPUFLOW features an improved physical model for the thermal and rheological evolution of lava flows, support for debris flows without thermal dependency and a parallel implementation on graphic processing units (GPUs). We estimate the influence that the GPUFLOW input parameters have on flow emplacement through different synthetic test cases and demonstrate its reliability through the 2014 pyroclastic flow and the 2018 eruption occurred at Etna volcano. This work was supported by the INGV project Pianeta Dinamico funded by MIUR (“Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese,” legge 145/2018), Tema 8 – PANACEA 2021.

 
On The Habitability Of An Impacted Young Earth 
Authors: Cerrillo Kaitlin E. , Pearce Ben K.D. , Mollière Paul , Pudritz Ralph E.
Published: March 2022

The formation of life on Earth is generally understood to have required the presence of liquid water, as well as an atmosphere within which the feedstock molecules — such as HCN — for more complex biomolecules are able to form. From the precipitation of these simple molecules, RNA can be built. The thermal profile and surface pressure of early Earth that was necessary for a liquid water cycle may have been created by a large impact, or series of larger impacts, following the formation of our Moon. Models which feature the consequences of very large impacts (e.g. Zahnle 2020) have dense, hydrogen-rich atmospheres that can be conductive to both the formation of HCN and a temperate surface temperature under the faint young Sun. In this work, we developed detailed self-consistent thermochemical equilibrium PT structures for post-large-impact atmospheres. We use a 1D radiative-convective equilibrium modelling code to obtain these thermal profiles and equilibrium chemistry. We found that the 5 optically thick cases for a dry atmosphere have a self-consistent surface temperature that is 742K on average; however, without the collisional opacity from H2 molecules contributing to the radiative transfer, this self-consistent surface temperature is an average of 394K. For a wet atmosphere, these values are 842K and 568K, respectively. Our current results suggest that, in the work of Zahnle et al. (2020), early post-impact HCN yields were computed for atmospheres that are initially too hot for the necessary liquid surface water and too hot for these molecules to be stable.
Efficient production of carbonyl sulfide in the low-NOx oxidation of dimethyl sulfide
Authors: Novelli Anna , Jernigan Christopher , Fite Charles , Vereecken Luc , Berkelhammer Max , Rollins Andrew , Rickly Pamela , Taraborelli Domenico , Holmes Christopher , Bertram Timothy
Published: March 2022

The oxidation of carbonyl sulfide (OCS) is the primary, continuous source of stratospheric sulfate aerosol particles, which can scatter shortwave radiation and catalyze heterogeneous reactions in the stratosphere. While it has been estimated that the oxidation of dimethyl sulfide (DMS), emitted from the surface ocean, accounts for 8-20% of the global OCS source, there is no existing DMS oxidation mechanism relevant to the marine atmosphere that is consistent with an OCS source of this magnitude. We describe new laboratory measurements and theoretical analyses of DMS oxidation that provide a mechanistic description for OCS production from hydroperoxymethyl thioformate (HPMTF), an ubiquitous, soluble DMS oxidation product.

The mechanism for OCS formation from DMS + OH is found to proceed through several intermediate stages, including secondary OH-initiated oxidation of hydroperoxymethyl thioformate (HOOCH2SCH=O), thioperformic anhydride (O=CHSCH=O), and thioperformic acid (HOOCH=S and HOSCH=O). Several of these reactions are affected by chemical activation, leading to prompt product formation. A theoretical kinetic analysis of these reactions and of conditions representative of the marine boundary layer shows several potential OCS formation channels, which combined lead to a high yield of OCS under OH-initiated oxidation of DMS.

We incorporate this chemical mechanism into a global chemical transport model, showing that OCS production from DMS is a factor of 3 smaller than current estimates and displays a maximum in the tropics consistent with field observations. A critical factor in the conversion of DMS to OCS is the heterogeneous loss of the soluble intermediates, making the OCS yield sensitive to multiphase cloud chemistry and reducing the total OCS formation.