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We introduce \texttt{featom}, an open source code that implements a high-order finite element solver for the radial Schr\"odinger, Dirac, and Kohn-Sham equations. The formulation accommodates various mesh types, such as uniform or exponential, and the convergence can be systematically controlled by increasing the number and/or polynomial order of the finite element basis functions. The Dirac equation is solved using a squared Hamiltonian approach to eliminate spurious states. To address the slow convergence of the $\kappa=\pm1$ states due to divergent derivatives at the origin, we incorporate known asymptotic forms into the solutions. We achieve a high level of accuracy ($10^{-8}$ Hartree) for total energies and eigenvalues of heavy atoms such as uranium in both Schr\"odinger and Dirac Kohn-Sham solutions. We provide detailed convergence studies and computational parameters required to attain commonly required accuracies. Finally, we compare our results with known analytic results as well as the results of other methods. In particular, we calculate benchmark results for atomic numbers ($Z$) from 1 to 92, verifying current benchmarks. We demonstrate significant speedup compared to the state-of-the-art shooting solver \texttt{dftatom}. An efficient, modular Fortran 2008 implementation, is provided under an open source, permissive license, including examples and tests, wherein particular emphasis is placed on the independence (no global variables), reusability, and generality of the individual routines. Comment: 30 pages, 3 tables, 6 figures, accepted in Elsevier's Computer Physics Communications

The microphysics of electron and photon propagation in liquid argon is a key component of detector design and calibrations needed to construct and perform measurements within a wide range of particle physics experiments. As experiments grow in scale and complexity, and as the precision of their intended measurements increases, the development of tools to investigate important microphysics effects impacting such detectors becomes necessary. In this paper we present a new time-domain Monte Carlo simulation of electron transport in liquid argon. The simulation models the TRANSport in Liquid Argon of near-Thermal Electrons (TRANSLATE) with the aim of providing a multi-purpose software package for the study and optimization of detector environments, with a particular focus on ongoing and next generation liquid argon neutrino experiments utilizing the time projection chamber technology. TRANSLATE builds on previous work of Wojcik and Tachiya, amongst others, introducing additional processes, including ionization, thus modeling the full range of drift electron scattering interactions. The simulation is validated by benchmarking its performance with swarm parameters from data collected in experimental setups operating in gas and liquid. Program Title:TRANSLATE CPC Library link to program files:https://doi.org/10.17632/v3tr6xp53h.1 Developer's repository link:https://github.com/davidc1/TRANSLATE Licensing provisions: GNU General Public License 3.0 Programming language: CImage 1, python External routines/libraries used: make, cmake (required), ipython notebook (optional) Nature of problem: Simulation of electron-argon scattering events at energies of 10−3−103 eV Solution method: Monte Carlo time-domain transport of electrons simulating momentum transfer, excitations, and ionization interaction modes utilizing input single and double-differential cross sections. Additional comments including restrictions and unusual features: Effects of ion space-charge or recombination with positive argon ions are not included. The microphysics of electron and photon propagation in liquid argon is a key component of detector design and calibrations needed to construct and perform measurements within a wide range of particle physics experiments. As experiments grow in scale and complexity, and as the precision of their intended measurements increases, the development of tools to investigate important microphysics effects impacting such detectors becomes necessary. In this paper we present a new time-domain Monte Carlo simulation of electron transport in liquid argon. The simulation models the TRANSport in Liquid Argon of near-Thermal Electrons (TRANSLATE) with the aim of providing a multi-purpose software package for the study and optimization of detector environments, with a particular focus on ongoing and next generation liquid argon neutrino experiments utilizing the time projection chamber technology. TRANSLATE builds on previous work of Wojcik and Tachiya, amongst others, introducing additional cross-section processes up to ionization, thus modeling the full range of drift electron scattering interactions. The simulation is validated by benchmarking its performance with swarm parameters from data collected in experimental setups operating in gas and liquid.

Knowing what happens over time to the lifeways of people in contemporary small-scale non-industrial societies of the rural Global South matters because it helps assess changes in the quality of life of underrepresented groups. It has been hard to answer the question because longitudinal information is rarely collected in such settings. A longitudinal dataset of nine years (2002-2010) from a horticultural-foraging society of Indigenous People in the Bolivian Amazon (Tsimane') is used for an exploratory analysis of micro-level trends in indicators of well-being and economic inequalities. We selected 13 Tsimane' villages (from ∼ 100) that varied in proximity to town and surveyed all households in each village. ∼ 240 households were followed yearly to estimate trends of 21 outcomes (e.g., income, sociality, macronutrients). For each economic outcome, annual and all-years-combined Gini coefficients were estimated for the entire sample across the 13 villages. We show a rise in total asset wealth, a change in asset composition (less traditional wealth, more commercial wealth), higher monetary value of foods eaten, and better-perceived health, but a decline in caloric and protein consumption and no marked gender differences in objective or hedonic measures of well-being. Economic inequalities were non-trivial and showed no marked trend but varied between years; asset inequality varied less than income inequality. We document the value of longitudinal, locally grounded indexes of well-being to obtain a granular view of micro-level changes in well-being and the possible use of inequality in the consumption of calories and macronutrients as a valid proxy for income inequality in rural areas of the Global South with tenuous links to the market economy. Unidad de excelencia María de Maeztu CEX2019-000940-M

In this letter, we introduce The Polar Vocabularies and Semantics Working Group, originally established as a joint effort between the joint SAON/IASC Arctic Data Committee and the Data Management Collaboration Team of the Interagency Arctic Research Policy Committee. We Invite, communities of practice to actively engage with us in our activities (described below), to advance the state of semantics-based applications in polar activities (and to increase interoperability between stakeholders and rights holders within existing and emerging digital ecosystems).

A new open source tool for fluid simulation of multi-component plasmas is presented, based on a flexible software design that is applicable to scientific simulations in a wide range of fields. This design enables the same code to be configured at run-time to solve systems of partial differential equations in 1D, 2D or 3D, either for transport (steady-state) or turbulent (time-evolving) problems, with an arbitrary number of ion and neutral species. To demonstrate the capabilities of this tool, applications relevant to the boundary of tokamak plasmas are presented: 1D simulations of diveror plasmas evolving equations for all charge states of neon and deuterium; 2D transport simulations of tokamak equilibria in single-null X-point geometry with plasma ion and neutral atom species; and simulations of the time-dependent propagation of plasma filaments (blobs). Hermes-3 is publicly available on Github under the GPL-3 open source license. The repository includes documentation and a suite of unit, integrated and convergence tests. Comment: Submitted to Computer Physics Communications

AbstractSignificant progress in permafrost carbon science made over the past decades include the identification of vast permafrost carbon stocks, the development of new pan‐Arctic permafrost maps, an increase in terrestrial measurement sites for CO2 and methane fluxes, and important factors affecting carbon cycling, including vegetation changes, periods of soil freezing and thawing, wildfire, and other disturbance events. Process‐based modeling studies now include key elements of permafrost carbon cycling and advances in statistical modeling and inverse modeling enhance understanding of permafrost region C budgets. By combining existing data syntheses and model outputs, the permafrost region is likely a wetland methane source and small terrestrial ecosystem CO2 sink with lower net CO2 uptake toward higher latitudes, excluding wildfire emissions. For 2002–2014, the strongest CO2 sink was located in western Canada (median: −52 g C m−2 y−1) and smallest sinks in Alaska, Canadian tundra, and Siberian tundra (medians: −5 to −9 g C m−2 y−1). Eurasian regions had the largest median wetland methane fluxes (16–18 g CH4 m−2 y−1). Quantifying the regional scale carbon balance remains challenging because of high spatial and temporal variability and relatively low density of observations. More accurate permafrost region carbon fluxes require: (a) the development of better maps characterizing wetlands and dynamics of vegetation and disturbances, including abrupt permafrost thaw; (b) the establishment of new year‐round CO2 and methane flux sites in underrepresented areas; and (c) improved models that better represent important permafrost carbon cycle dynamics, including non‐growing season emissions and disturbance effects.

Today, relatively warm Circumpolar Deep Water is melting Thwaites Glacier at the base of its ice shelf and at the grounding zone, contributing to significant ice retreat. Accelerating ice loss has been observed since the 1970s; however, it is unclear when this phase of significant melting initiated. We analyzed the marine sedimentary record to reconstruct Thwaites Glacier’s history from the early Holocene to present. Marine geophysical surveys were carried out along the floating ice-shelf margin to identify core locations from various geomorphic settings. We use sedimentological data and physical properties to define sedimentary facies at seven core sites. Glaciomarine sediment deposits reveal that the grounded ice in the Amundsen Sea Embayment had already retreated to within ~45 km of the modern grounding zone prior to ca. 9,400 y ago. Sediments deposited within the past 100+ y record abrupt changes in environmental conditions. On seafloor highs, these shifts document ice-shelf thinning initiating at least as early as the 1940s. Sediments recovered from deep basins reflect a transition from ice proximal to slightly more distal conditions, suggesting ongoing grounding-zone retreat since the 1950s. The timing of ice-shelf unpinning from the seafloor for Thwaites Glacier coincides with similar records from neighboring Pine Island Glacier. Our work provides robust new evidence that glacier retreat in the Amundsen Sea was initiated in the mid-twentieth century, likely associated with climate variability.

cti_cross_region_taxon This repository provides the data and codes used in the manuscript: Guillem Chust, Ernesto Villarino, Matthew McLean, Nova Mieszkowska, Lisandro Benedetti-Cecchi, Fabio Bulleri, Chiara Ravaglioli, Angel Borja, Iñigo Muxika, José A. Fernandes-Salvador, Leire Ibaibarriaga, Ainhize Uriarte, Marta Revilla, Fernando Villate, Arantza Iriarte, Ibon Uriarte, Soultana Zervoudaki, Jacob Carstensen, Paul J. Somerfield, Ana M. Queirós , Andrea J. McEvoy, Arnaud Auber, Manuel Hidalgo, Marta Coll, Joaquim Garrabou, Daniel Gómez-Gras, Cristina Linares, Francisco Ramírez, Núria Margarit, Mario Lepage, Chloé Dambrine, Jérémy Lobry, Myron A. Peck, Paula de la Barra, Anieke van Leeuwen, Gil Rilov, Erez Yeruham, Anik Brind'Amour, and Martin Lindegren. Cross-basin and cross-taxa patterns of marine community tropicalization and deborealization in warming European seas. Nature Communications Please check the github repo cti_cross_region_taxon for updates. Abstract Ocean warming and acidification, decreases in dissolved oxygen concentrations, and changes in primary production are causing an unprecedented global redistribution of marine life. The identification of underlying ecological processes underpinning marine species turnover, particularly the prevalence of tropicalization over deborealization, has been recently debated in the context of ocean warming. Here, we track changes in the mean thermal affinity of marine communities across European seas by calculating the Community Temperature Index for 65 biodiversity time series collected over four decades and containing 1,817 species from different communities (zooplankton, coastal benthos, pelagic and demersal invertebrates and fish). We show most communities and sites have clearly responded to ongoing ocean warming via abundance increases of warm-water species (tropicalization; 54%) and decreases of cold-water species (deborealization; 18%). Tropicalization dominated Atlantic sites compared to semi-enclosed basins such as the Mediterranean and Baltic Seas, probably due to physical barrier constraints to connectivity and species colonization. Semi-enclosed basins appeared to be particularly vulnerable to ocean warming, experiencing the fastest rates of warming and biodiversity loss through deborealization. Keywords: climate change, community temperature index, CTI, ocean connectivity. Acknowledgements This study has been supported by the European Union's Horizon 2020 research and innovation programme under grant agreement No 869300 (FutureMARES project) (G.C., E.V., J.F-S., M.P., M.Lin., C.D., D.G-G., G.R., L.B., C.R., M.C., F.R., G.R., P.B., M.P., M.Lep., J.L., A.B., N.M., J.G., F.B., L.B.C, A.Q., F.V., A.I., and I.U.), and by the Urban Klima 2050 -- LIFE 18 IPC 000001 project, which has been received funding from European Union's LIFE programme (G.C., E.V., L.I., A.B., A.U., and M.R.). Additional financial support was obtained from the Basque Government (PIBA2020-1-0028 & IT1723-22). We thank the NOAA Climate Prediction Center for providing Sea Temperature data through the NCEP Global Ocean Data Assimilation System (GODAS) www.cpc.ncep.noaa.gov/products/GODAS. We also thank Ocean Biodiversity Information System (OBIS) for providing global occurrences of the biological group studied here. Data from the Basque Country were obtained from the Basque Water Agency (URA) monitoring network, through a Convention with AZTI. M.C., J.G., D.G.-G. and F.R. acknowledge the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S). Authors M.H. and M.Lin. are grateful for the support from ICES Working Group on Comparative Ecosystem-based Analyses of Atlantic and Mediterranean marine systems (WGCOMEDA) for this research. This paper is contribution nº xxxx from AZTI, Marine Research, Basque Research and Technology Alliance (BRTA)