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Microbialites are known from a range of terrestrial, freshwater, marine, and marginal settings. The descriptive terminology used in each instance depends largely on the historical legacy derived from previous studies in similar environments. This has led to a diversity of nomenclature and a lack of conformity in the terms used to describe and categorise microbialites. As the role of microbial mats and biofilms is increasingly recognised in the formation of tufa and terrestrial carbonates, deposits such as tufa microbialites bridge the spectrum of microbialites and terrestrial carbonate deposits. Groundwater spring-fed tufa microbialites in supratidal rock coast environments that occur at the interface of terrestrial and marine domains demonstrate the need for an integrative and systematic nomenclature approach. To date, their global distribution and complex relationships with pre-defined deposits have resulted in the application of a variety of descriptive terminologies, most frequently at the macro- and mesoscale. Here we review and consolidate the multi-scale library of terminologies for microbialites and present a new geomorphological scheme for their description and classification. This scheme has greater alignment with terrestrial carbonate nomenclature at the macroscale and with marine and lacustrine microbialites at the mesoscale. The proposed terminology can primarily be applied to tufa microbialites in spring-fed supratidal environments but may also be applicable in other relevant depositional environments including terrestrial carbonates, microbial mats, and other microbialites.

Galactic cosmic rays (GCRs) interact with matter in the atmosphere and at the surface of the Earth to produce a range of cosmogenic nuclides. Measurements of cosmogenic nuclides produced in surface rocks have been used to study past land ice extent as well as to estimate erosion rates. Because the GCR flux reaching the Earth is modulated by magnetic fields (solar and Earth's), records of cosmogenic nuclides produced in the atmosphere have also been used for studies of past solar activity. Studies utilizing cosmogenic nuclides assume that the GCR flux is constant in time, but this assumption may be uncertain by 30 % or more. Here we propose that measurements of 14C of carbon monoxide (14CO) in ice cores at low-accumulation sites can be used as a proxy for variations in GCR flux on timescales of several thousand years. At low-accumulation ice core sites, 14CO in ice below the firn zone originates almost entirely from in situ cosmogenic production by deep-penetrating secondary cosmic ray muons. The flux of such muons is almost insensitive to solar and geomagnetic variations and depends only on the primary GCR flux intensity. We use an empirically constrained model of in situ cosmogenic 14CO production in ice in combination with a statistical analysis to explore the sensitivity of ice core 14CO measurements at Dome C, Antarctica, to variations in the GCR flux over the past ≈ 7000 years. We find that Dome C 14CO measurements would be able to detect a linear change of 6 % over 7 ka, a step increase of 6 % at 3.5 ka or a transient 100-year spike of 190 % at 3.5 ka at the 3σ significance level. The ice core 14CO proxy therefore appears promising for the purpose of providing a high-precision test of the assumption of GCR flux constancy over the Holocene.

Measurements of carbon-14-containing carbon monoxide (14CO) in glacial ice are useful for studies of the past oxidative capacity of the atmosphere as well as for reconstructing the past cosmic ray flux. The 14CO abundance in glacial ice represents the combination of trapped atmospheric 14CO and in situ cosmogenic 14CO. The systematics of in situ cosmogenic 14CO production and retention in ice are not fully quantified, posing an obstacle to interpretation of ice core 14CO measurements. Here we provide the first comprehensive characterization of 14CO at an ice accumulation site (Summit, Greenland), including measurements in the ice grains of the firn matrix, firn air and bubbly ice below the firn zone. The results are interpreted with the aid of a firn gas transport model into which we implemented in situ cosmogenic 14C. We find that almost all (≈ 99.5 %) of in situ 14CO that is produced in the ice grains in firn is very rapidly (in <1 year) lost to the open porosity and from there mostly vented to the atmosphere. The timescale of this rapid loss is consistent with what is expected from gas diffusion through ice. The small fraction of in situ 14CO that initially stays in the ice grains continues to slowly leak out to the open porosity at a rate of ≈ 0.6 % yr−1. Below the firn zone we observe an increase in 14CO content with depth that is due to in situ 14CO production by deep-penetrating muons, confirming recent estimates of 14CO production rates in ice via the muon mechanisms and allowing for narrowing constraints on these production rates.

Seismicity at glaciers, ice sheets, and ice shelves provides observational constraint on a number of glaciological processes. Detecting and locating this seismicity, specifically icequakes, is a necessary first step in studying processes such as basal slip, crevassing, imaging ice fabric, and iceberg calving, for example. Most glacier deployments to date use conventional seismic networks, comprised of seismometers distributed over the entire area of interest. However, smaller-aperture seismic arrays can also be used, which are typically sensitive to seismicity distal from the array footprint and require a smaller number of instruments. Here, we investigate the potential of arrays and array-processing methods to detect and locate subsurface microseismicity at glaciers, benchmarking performance against conventional seismic-network-based methods for an example at an Antarctic ice stream. We also provide an array-processing recipe for body-wave cryoseismology applications. Results from an array and a network deployed at Rutford Ice Stream, Antarctica, show that arrays and networks both have strengths and weaknesses. Arrays can detect icequakes from further distances, whereas networks outperform arrays in more comprehensive studies of a particular process due to greater hypocentral constraint within the network extent. We also gain new insights into seismic behaviour at the Rutford Ice Stream. The array detects basal icequakes in what was previously interpreted to be an aseismic region of the bed, as well as new icequake observations downstream and at the ice stream shear margins, where it would be challenging to deploy instruments. Finally, we make some practical recommendations for future array deployments at glaciers.

One of the key components of this research has been the mapping of Antarctic bed topography and ice thickness parameters that are crucial for modelling ice flow and hence for predicting future ice loss and the ensuing sea level rise. Supported by the Scientific Committee on Antarctic Research (SCAR), the Bedmap3 Action Group aims not only to produce new gridded maps of ice thickness and bed topography for the international scientific community, but also to standardize and make available all the geophysical survey data points used in producing the Bedmap gridded products. Here, we document the survey data used in the latest iteration, Bedmap3, incorporating and adding to all of the datasets previously used for Bedmap1 and Bedmap2, including ice bed, surface and thickness point data from all Antarctic geophysical campaigns since the 1950s. More specifically, we describe the processes used to standardize and make these and future surveys and gridded datasets accessible under the Findable, Accessible, Interoperable, and Reusable (FAIR) data principles. With the goals of making the gridding process reproducible and allowing scientists to re-use the data freely for their own analysis, we introduce the new SCAR Bedmap Data Portal (https://bedmap.scar.org, last access: 1 March 2023) created to provide unprecedented open access to these important datasets through a web-map interface. We believe that this data release will be a valuable asset to Antarctic research and will greatly extend the life cycle of the data held within it. Data are available from the UK Polar Data Centre: https://data.bas.ac.uk (last access: 5 May 2023​​​​​​​). See the Data availability section for the complete list of datasets.

Cosmic rays entering the Earth's atmosphere produce showers of secondary particles such as protons, neutrons, and muons. The interaction of these particles with oxygen-16 (16O) in minerals such as ice and quartz can produce carbon-14 (14C). In glacial ice, 14C is also incorporated through trapping of 14C-containing atmospheric gases (14CO2, 14CO, and 14CH4). Understanding the production rates of in situ cosmogenic 14C is important to deconvolve the in situ cosmogenic and atmospheric 14C signals in ice, both of which contain valuable paleoenvironmental information. Unfortunately, the in situ 14C production rates by muons (which are the dominant production mechanism at depths of >6 m solid ice equivalent) are uncertain. In this study, we use measurements of in situ 14C in ancient ice (>50 ka) from the Taylor Glacier, an ablation site in Antarctica, in combination with a 2D ice flow model to better constrain the compound-specific rates of 14C production by muons and the partitioning of in situ 14C between CO2, CO, and CH4. Our measurements show that 33.7 % (±11.4 %; 95 % confidence interval) of the produced cosmogenic 14C forms 14CO and 66.1 % (±11.5 %; 95 % confidence interval) of the produced cosmogenic 14C forms 14CO2. 14CH4 represents a very small fraction (%) of the total. Assuming that the majority of in situ muogenic 14C in ice forms 14CO2, 14CO, and 14CH4, we also calculated muogenic 14C production rates that are lower by factors of 5.7 (3.6–13.9; 95 % confidence interval) and 3.7 (2.0–11.9; 95 % confidence interval) for negative muon capture and fast muon interactions, respectively, when compared to values determined in quartz from laboratory studies (Heisinger et al., 2002a, b) and in a natural setting (Lupker et al., 2015). This apparent discrepancy in muogenic 14C production rates in ice and quartz currently lacks a good explanation and requires further investigation.

Three holes were drilled to the bed of Rutford Ice Stream, through ice up to 2154 m thick, to investigate the basal processes and conditions associated with fast ice flow and the glacial history of the West Antarctic Ice Sheet. A narrative of the drilling, measuring and sampling activities, as well as some preliminary results and initial interpretations of subglacial conditions, is given. These were the deepest subglacial access holes ever drilled using the hot-water drilling method. Samples of bed and englacial sediments were recovered, and a number of instruments were installed in the ice column and the bed. The ice–bed interface was found to be unfrozen, with an existing, well-developed subglacial hydrological system at high pressure, within ~1% of the ice overburden. The bed itself comprises soft, water-saturated sediments, consistent with previous geophysical interpretations. Englacial sediment quantity varies significantly between two locations ~2 km apart, and possibly over even shorter (~20 m) distances. Difficulties and unusual observations encountered while connecting to the subglacial hydrological system in one hole possibly resulted from the presence of a large clast embedded in the bottom of the ice.

There is now a wealth of data to calculate global flood exposure. Available datasets differ in detail and representation of both global population distribution and global flood hazard. Previous studies of global flood risk have used datasets interchangeably without addressing the impacts using different datasets could have on exposure estimates. By calculating flood exposure to different sized rivers using a model-independent geomorphological river flood susceptibility map (RFSM), we show that limits placed on the size of river represented in global flood models result in global flood exposure estimates that differ by more than a factor of 2. The choice of population dataset is found to be equally important and can have enormous impacts on national flood exposure estimates. Up-to-date, high-resolution population data are vital for accurately representing exposure to smaller rivers and will be key in improving the global flood risk picture. Our results inform the appropriate application of these datasets and where further development and research are needed.

Antarctic ice sheet history is imprinted in the structure and fabric of the ice column. At ice rises, the signature of ice flow history is preserved due to the low strain rates inherent at these independent ice flow centres. We present results from a distributed acoustic sensing (DAS) experiment at Skytrain Ice Rise in the Weddell Sea sector of West Antarctica, aimed at delineating the englacial fabric to improve our understanding of ice sheet history in the region. This pilot experiment demonstrates the feasibility of an innovative technique to delineate ice rise structure. Both direct and reflected P- and S-wave energy, as well as surface wave energy, are observed using a range of source offsets, i.e. a walkaway vertical seismic profile, recorded using fibre optic cable. Significant noise, which results from the cable hanging untethered in the borehole, is modelled and suppressed at the processing stage. At greater depth where the cable is suspended in drilling fluid, seismic interval velocities and attenuation are measured. Vertical P-wave velocities are high (VINT=3984±218 m s−1) and consistent with a strong vertical cluster fabric. Seismic attenuation is high (QINT=75±12) and inconsistent with previous observations in ice sheets over this temperature range. The signal level is too low, and the noise level too high, to undertake analysis of englacial fabric variability. However, modelling of P- and S-wave travel times and amplitudes with a range of fabric geometries, combined with these measurements, demonstrates the capacity of the DAS method to discriminate englacial fabric distribution. From this pilot study we make a number of recommendations for future experiments aimed at quantifying englacial fabric to improve our understanding of recent ice sheet history.

Teachers are in a profession with high levels of stress, which play a role in absenteeism and burnout. Many studies have focused on teacher burnout; however, limited literature has examined how to support teacher well-being. Based on my research of school wellness initiatives, I discovered that the role and significance of teachers is the linchpin for establishing and sustaining school health. This article focuses on the stakeholders involved in the work of building a healthy school community, the role of school divisions, and how the whole school community benefits from teachers who are provided psychological health and safety supports in the workplace.

Early mobility in the Intensive Care Unit (ICU) can improve a multitude of patient outcomes, and occupational therapists (OTs) play a valuable role as part of the interprofessional team, with the ability to address activities of daily living, functional cognition, psychological and communication needs, and more. In 2022, the first iteration of an ICU interprofessional education simulation (Sim-IPE) yielded poor outcomes for OT students. This study aimed to modify existing pre-learning activities in the Sim-IPE's second iteration to improve OT students' perceptions and professional role awareness in interprofessional ICU care. Students from Doctor of OT, Bachelor of Science Nursing, Doctor of Physical Therapy (PT), and Associate Program Respiratory Therapy programs from one university participated in an ICU Early Mobility Sim-IPE with enhanced pre-learning activities and environmental modifications targeting OT student outcomes. Investigators employed a mixed methods approach, including pre/post quantitative analysis through the SPICE-R2 instrument and qualitative analysis of OT students' written reflections. Quantitatively, OT students (n = 12) demonstrated significant improvement in SPICE-R2 scores from pre- to post-Sim-IPE, as well as significant improvements when compared to OT student scores from the first iteration. Qualitatively, OT students reflected improved role awareness when compared to OT students from the first Sim-IPE, however, continue to struggle with role assertion and ambiguity, particularly with PT students. This study improved the OT students' Sim-IPE experience; specifically, role awareness and perceptions of interprofessional practice. Residual challenges in role assertion and ambiguity offer opportunities for future intervention and research.

The current study investigated perfectionism and procrastination from the trait and cognitive perspectives and addressed how they relate to components of a personal orientation toward failure. A sample of 327 undergraduate students completed three perfectionism measures (i.e., Frost Multidimensional Perfectionism Scale, Hewitt-Flett Multidimensional Perfectionism Scale, and Perfectionism Cognitions Inventory), two procrastination measures (i.e., Lay Procrastination Scale and Procrastinatory Cognitions Inventory), and measures of fear of failure and overgeneralizing failure. Correlational analyses showed that the composite trait dimension of perfectionistic concerns and the cognitive dimension of perfectionistic automatic thoughts had modest links with trait procrastination but much stronger links with the cognitive measure of procrastinatory automatic thoughts. All perfectionism and procrastination measures were significantly correlated with fear of failure and overgeneralization of failure. More extensive analyses showed that fear of failure mediated trait and cognitive pathways between perfectionism and procrastination, and the overgeneralization of failure mediated most pathways. Other evidence supported a sequential mediation between perfectionism and procrastination (i.e., fear of failure followed by the overgeneralization of failure). Overall, the results suggest that procrastinating perfectionists have a cognitive hypersensitivity to failure and a potentially debilitating form of perfectionistic reactivity characterized by overgeneralizing failures to the self. The theoretical and practical implications are discussed.

The Perfectionism Social Disconnection Model (PSDM) and the Existential Model of Perfectionism and Depressive Symptoms (EMPDS) are promising models of perfectionism and psychopathology. However, research examining suicide ideation within the PSDM is scarce, and no research has examined suicide ideation as an outcome in the EMPDS. Moreover, tests of the PSDM and EMPDS have been conducted separately and most research has examined the PSDM and EMPDS using cross-sectional or two-wave longitudinal designs, which do not provide a satisfactory test of mediation. In the current study, we addressed these limitations by testing whether perfectionism confers vulnerability to suicide ideation via feelings of mattering and anti-mattering (from the PSDM) and via difficulty accepting the past (from the EMPDS) in a three-wave longitudinal design in two independent samples of undergraduate students and community adults. Participants completed measures on three occasions over 6 weeks. Findings revealed that socially prescribed perfectionism indirectly predicted suicide ideation via difficulty accepting the past in both samples. In addition, in the undergraduate sample only, socially prescribed perfectionism indirectly predicted higher suicide ideation via anti-mattering, and self-oriented perfectionism indirectly predicted higher suicide ideation via mattering. Based on our findings, we advocate for future research to include suicide ideation in the PSDM and EMPDS, to integrate explanatory models, and to examine a mattering-specific EMPDS.

Friendships are important for the mental well-being of emerging adults. Socially prescribed perfectionism, where individuals feel pressured to be perfect by others, can be destructive, leading to conflict with others, depressive symptoms, and problematic drinking. However, its impact on friendships is not well-explored. This study examined 174 emerging adult friendship dyads using a 4-wave, 4-month dyadic design. Data were analyzed using longitudinal actor-partner interdependence models. Using a novel friend-specific measure of socially prescribed perfectionism, we found that an individual's perceived expectation to be perfect from a friend was positively associated with increased conflict between friends, as well as with higher levels of depressive symptoms and problematic drinking in the individual. Findings lend credence to longstanding theoretical accounts and case histories suggesting socially prescribed perfectionism leads to harmful individual and relational outcomes and extends them to the specific context of friendships.

Important uncertainties remain in our understanding of the spatial and temporal variability of atmospheric hydroxyl radical concentration ([OH]). Carbon-14-containing carbon monoxide (14CO) is a useful tracer that can help in the characterization of [OH] variability. Prior measurements of atmospheric 14CO concentration ([14CO] are limited in both their spatial and temporal extent, partly due to the very large air sample volumes that have been required for measurements (500–1000 L at standard temperature and pressure, L STP) and the difficulty and expense associated with the collection, shipment, and processing of such samples. Here we present a new method that reduces the air sample volume requirement to ≈90 L STP while allowing for [14CO] measurement uncertainties that are on par with or better than prior work (≈3 % or better, 1σ). The method also for the first time includes accurate characterization of the overall procedural [14CO] blank associated with individual samples, which is a key improvement over prior atmospheric 14CO work. The method was used to make measurements of [14CO] at the NOAA Mauna Loa Observatory, Hawaii, USA, between November 2017 and November 2018. The measurements show the expected [14CO] seasonal cycle (lowest in summer) and are in good agreement with prior [14CO] results from another low-latitude site in the Northern Hemisphere. The lowest overall [14CO] uncertainties (2.1 %, 1σ) are achieved for samples that are directly accompanied by procedural blanks and whose mass is increased to ≈50 µgC (micrograms of carbon) prior to the 14C measurement via dilution with a high-CO 14C-depleted gas.

Continental–global-scale flood hazard models simulate design floods, i.e. theoretical flood events of a given probability. Since they output phenomena unobservable in reality, large-scale models are typically compared to more localised engineering models to evidence their accuracy. However, both types of model may share the same biases and so not validly illustrate their predictive skill. Here, we adapt an existing continental-scale design flood framework of the contiguous US to simulate historical flood events. A total of 35 discrete events are modelled and compared to observations of flood extent, water level, and inundated buildings. Model performance was highly variable, depending on the flood event chosen and validation data used. While all events were accurately replicated in terms of flood extent, some modelled water levels deviated substantially from those measured in the field. Despite this, the model generally replicated the observed flood events in the context of terrain data vertical accuracy, extreme discharge measurement uncertainties, and observational field data errors. This analysis highlights the continually improving fidelity of large-scale flood hazard models, yet also evidences the need for considerable advances in the accuracy of routinely collected field and high-river flow data in order to interrogate flood inundation models more comprehensively.

Subglacial water plays an important role in ice sheet dynamics and stability. Subglacial lakes are often located at the onset of ice streams and have been hypothesised to enhance ice flow downstream by lubricating the ice–bed interface. The most recent subglacial-lake inventory of Antarctica mapped nearly 400 lakes, of which ∼ 14 % are found in West Antarctica. Despite the potential importance of subglacial water for ice dynamics, there is a lack of detailed subglacial-water characterisation in West Antarctica. Using radio-echo sounding data, we analyse the ice–bed interface to detect subglacial lakes. We report 33 previously uncharted subglacial lakes and present a systematic analysis of their physical properties. This represents a ∼ 40 % increase in subglacial lakes in West Antarctica. Additionally, a new digital elevation model of basal topography of the Ellsworth Subglacial Highlands was built and used to create a hydropotential model to simulate the subglacial hydrological network. This allows us to characterise basal hydrology, determine subglacial water catchments and assess their connectivity. We show that the simulated subglacial hydrological catchments of the Rutford Ice Stream, Pine Island Glacier and Thwaites Glacier do not correspond to their ice surface catchments.

The publicly funded early intervention program for preschoolers with autism spectrum disorder (ASD) in Nova Scotia, Canada, uses the pivotal response treatment (PRT) model. Parents are coached in use of PRT strategies during their children's first week of treatment. We explored whether parents of older preschoolers with limited verbal ability learned to implement PRT strategies with fidelity after brief coaching and whether PRT strategy use was associated with gains in children's communication skills. We coded precoaching and postcoaching parent-child play episodes of 39 children (4.4-5.5 years) with limited verbal skills for parents' PRT fidelity and children's correct responding to language opportunities and frequency of initiations. Parents' use of PRT strategies significantly improved, as did children's responsiveness to parent-provided language opportunities. This study provides evidence for the utility of brief parent coaching in PRT for older preschoolers with ASD whose verbal skills are limited.

The Big Three Perfectionism Scale (BTPS) was created to integrate different aspects of perfectionism, including the newly conceptualized concept of narcissistic perfectionism. The goal of our two studies (N = 1341) was to examine the psychometric properties of the Polish adaptation of the BTPS, supporting the validity and portability of the measure. The studies were conducted among people who had a child, thus contributing to a better understanding of parental perfectionism, one of the key factors influencing parental well-being and a child's functioning. Our analyses included investigating the structure of the scale, intercorrelations between subscales, reliability, and convergent validity by correlating BTPS scores with other measures of perfectionism and correlates of psychopathology (borderline symptoms) and parental difficulties (parental stress and parental burnout). Results supported the structure of the original BTPS. As predicted, confirmatory factor analysis indicated that items comprising the Polish adaptation of the questionnaire, like the original version, measure three related but specific aspects of perfectionism: rigid perfectionism, self-critical perfectionism, and narcissistic perfectionism. The three dimensions were also found to be specifically related to the difficulties experienced by parents. Further, the Polish version of the BTPS was found to have good internal reliability and validity. Our results from two independent Polish samples suggest that the Polish version of the BTPS is a psychometrically robust measure of perfectionism for assessing the three perfectionism factors.

Ice core records of the major atmospheric greenhouse gases (CO2, CH4, N2O) and their isotopologues covering recent centuries provide evidence of biogeochemical variations during the Late Holocene and pre-industrial periods and over the transition to the industrial period. These records come from a number of ice core and firn air sites and have been measured in several laboratories around the world and show common features but also unresolved differences. Here we present revised records, including new measurements, performed at the CSIRO Ice Core Extraction LABoratory (ICELAB) on air samples from ice obtained at the high-accumulation site of Law Dome (East Antarctica). We are motivated by the increasing use of the records by the scientific community and by recent data-handling developments at CSIRO ICELAB. A number of cores and firn air samples have been collected at Law Dome to provide high-resolution records overlapping recent, direct atmospheric observations. The records have been updated through a dynamic link to the calibration scales used in the Global Atmospheric Sampling LABoratory (GASLAB) at CSIRO, which are periodically revised with information from the latest calibration experiments. The gas-age scales have been revised based on new ice-age scales and the information derived from a new version of the CSIRO firn diffusion model. Additionally, the records have been revised with new, rule-based selection criteria and updated corrections for biases associated with the extraction procedure and the effects of gravity and diffusion in the firn. All measurements carried out in ICELAB–GASLAB over the last 25 years are now managed through a database (the ICElab dataBASE or ICEBASE), which provides consistent data management, automatic corrections and selection of measurements, and a web-based user interface for data extraction. We present the new records, discuss their strengths and limitations, and summarise their main features. The records reveal changes in the carbon cycle and atmospheric chemistry over the last 2 millennia, including the major changes of the anthropogenic era and the smaller, mainly natural variations beforehand. They provide the historical data to calibrate and test the next inter-comparison of models used to predict future climate change (Coupled Model Inter-comparison Project – phase 6, CMIP6). The datasets described in this paper, including spline fits, are available at https://doi.org/10.25919/5bfe29ff807fb (Rubino et al., 2019).

The recent rapid growth of rifts in the Brunt Ice Shelf appears to signal the onset of its largest calving event since records began in 1915. The aim of this study is to determine whether this calving event will lead to a new steady state in which the Brunt Ice Shelf remains in contact with the bed, or an unpinning from the bed, which could predispose it to accelerated flow or possible break-up. We use a range of geophysical data to reconstruct the sea-floor bathymetry and ice shelf geometry, to examine past ice sheet configurations in the Brunt Basin, and to define the present-day geometry of the contact between the Brunt Ice Shelf and the bed. Results show that during past ice advances grounded ice streams likely converged in the Brunt Basin from the south and east. As the ice retreated, it was likely pinned on at least three former grounding lines marked by topographic highs, and transverse ridges on the flanks of the basin. These may have subsequently formed pinning points for developing ice shelves. The ice shelf geometry and bathymetry measurements show that the base of the Brunt Ice Shelf now only makes contact with one of these topographic highs. This contact is limited to an area of less than 1.3 to 3 km2 and results in a compressive regime that helps to maintain the ice shelf's integrity. The maximum overlap between ice shelf draft and the bathymetric high is 2–25 m and is contingent on the presence of incorporated iceberg keels, which protrude beneath the base of the ice shelf. The future of the ice shelf depends on whether the expected calving event causes full or partial loss of contact with the bed and whether the subsequent response causes re-grounding within a predictable period or a loss of structural integrity resulting from properties inherited at the grounding line.

The East Antarctic Ice Sheet discharges into the Weddell Sea via the Coats Land ice margin. We have used geophysical data to determine the changing ice-sheet configuration in this region through its last glacial advance and Holocene retreat and to identify constraints on its future stability. Methods included high-resolution multibeam bathymetry, sub-bottom profiles, seismic-reflection profiles, sediment core analysis and satellite altimetry. These provide evidence that Coats Land glaciers and ice streams merged with the palaeo-Filchner Ice Stream during the last glacial advance. Retreat of this ice stream from 12 848 to 8351 cal. yr BP resulted in its progressive southwards decoupling from Coats Land outlet glaciers. Moraines and grounding-zone wedges document the subsequent retreat and thinning of these glaciers, their loss of contact with the bed and the formation of ice shelves, which re-advanced to pinning points on topographic highs at the distal end of the troughs. Once fully detached from the bed, these ice shelves were predisposed to rapid retreat back to coastal grounding lines. This was due to reverse-bed slopes, the consequent absence of further pinning points in the troughs and potentially to the loss of structural integrity resulting from weaknesses inherited at the grounding line. These processes explain why there are no large ice shelves in the eastern Weddell Sea between 75.5 and 77° S.

Projections of sea-level rise contributions from West Antarctica's dynamically thinning ice streams contain high uncertainty because some of the key processes involved are extremely challenging to observe. An especially poorly observed parameter is sub-decadal stability of ice-stream beds, which may be important for subglacial traction, till continuity and landform development. Only two previous studies have made repeated geophysical measurements of ice-stream beds at the same locations in different years, but both studies were limited in spatial extent. Here, we present the results from repeat radar measurements of the bed of Pine Island Glacier, West Antarctica, conducted 3–6 years apart, along a cumulative ∼ 60 km of profiles. Analysis of the correlation of bed picks between repeat surveys shows that 90 % of the bed displays no significant change despite the glacier increasing in speed by up to 40 % over the last decade. We attribute the negligible detection of morphological change at the bed of Pine Island Glacier to the ubiquitous presence of a deforming till layer, wherein sediment transport is in steady state, such that sediment is transported along the basal interface without inducing morphological change to the radar-sounded basal interface. Given the precision of our measurements, the upper limit of subglacial erosion observed here is 500 mm a−1, far exceeding erosion rates reported for glacial settings from proglacial sediment yields, but substantially below subglacial erosion rates of 1.0 m a−1 previously reported from repeat geophysical surveys in West Antarctica.

Spatial localization of genetic information is important for tissue heterogeneity but difficult to capture with current analytical techniques. Here the authors present “Pixelated RT-LAMP”, an approach that uses parallel on-chip reactions to provide the distribution of target sequences directly from tissue.

Background: Identifying as an engineer is essential for belonging and student success, yet the social context and professional norms make it more difficult for some students to establish an identity as an engineer. Purpose/Hypothesis: This study investigated whether first-generation college students' funds of knowledge supported their engineering role identity. Design/Methods: Data came from a survey administered across the United States western, southern, and mountain regions in the fall semester of 2018. Only the sample of students who indicated they were the first in their families to attend college was used in the analysis (n = 378). Structural equation modeling was used to understand how first-generation college students' funds of knowledge supported their engineering role identity; measurement invariance was examined to ensure that the model was valid for women and men alike. Results: First-generation college students' funds of knowledge individually supported the components of the engineering role identity development process. Tinkering knowledge from home and perspective-taking helped inform interest and performance/competence beliefs. First-generation college students' bids for external recognition were supported through their mediational skills, their connecting experiences, and their local network of college friends. The bundle of advice, resources, and emotional support from family members was the only fund of knowledge that directly supported students' perceptions of themselves as engineers. Conclusions: The relationships we established between first-generation college students' funds of knowledge and emerging engineering role identities call for engineering educators to integrate students' funds of knowledge into engineering learning and to broaden disciplinary norms of what counts as engineering-relevant knowledge.

We present a digital elevation model of the bed of Rutford Ice Stream, Antarctica, derived from radio-echo sounding data. The data cover an 18 × 40 km area immediately upstream of the grounding line of the ice stream. This area is of particular interest because repeated seismic surveys have shown that rapid erosion and deposition of subglacial sediments has taken place. The bed topography shows a range of different subglacial landforms including mega-scale glacial lineations, drumlins and hummocks. This data set will form a baseline survey which, when compared to future surveys, should reveal how active subglacial landscapes change over time. These data also allow comparison between subglacial landforms in an active system with those observed in deglaciated areas in both polar regions. The data set comprises observed ice thickness data, an interpolated bed elevation grid, observed surface elevation data and a surface elevation grid. The data set is available at http://doi.org/269.

Universal school-based social and emotional learning (SEL) programs have been shown to have a range of benefits for students. However, these programs tend to focus on students, not involving parents, which may limit their impact outside the school context. We conducted focus groups and interviews with 118 parents, 58 teachers, and 6 school administrators at six public elementary schools across the United States implementing the Second Step SEL program to determine (a) what parents want to know about SEL in their children's schools and why, (b) what parents actually know about SEL in their children's schools, and (c) educators' perspectives on SEL communication with parents. The findings suggest that school staff underestimate parents' interest in knowing what their children are learning in SEL at school and perceive logistical barriers to SEL communication with parents. Accordingly, many parents report lacking knowledge about SEL despite valuing that knowledge and wishing to support their children's SEL development. These findings point to ways SEL programs can be designed to better communicate with parents, and importantly, to facilitate parental engagement in the development of their children's SEL skills.

The United Kingdom's (UK) goal of a 20% increase in participation of Black, Asian and Minority Ethnic (BAME) groups in higher education (HE) by 2020 has not been met. Pakistani and Bangladeshi students are some of the most underrepresented BAME groups in UK HE institutions. This systematic review included 20 papers that identified barriers and facilitators towards participation in HE separately for Pakistani and Bangladeshi students in the UK. Using thematic analysis, two overarching themes were constructed: (i) the interplay of culturally expected roles on HE participation and (ii) belief that HE is vital for success. This review identified the importance of role models to challenge cultural values that restrict women from participating in HE. Many parents and children viewed HE as a route to personal and community success. The findings support the relevancy of social learning theory in driving change for models of widening participation.

This study describes the development of a 12-item inventory of school supports for military-connected (MC) children. Participants were 444 students (grades 3 or 5) with an active-duty military parent (48% female; 57.3% White, 10.7% Black, 6.2% Native American, 5% Asian, 3.3% Pacific Islander, 17.5% bi/multiracial; 19% Latinx). Youth completed the Inventory of School Supports--Youth Report (ISS-YR) and measures of academic efficacy, parental involvement in school, school connectedness, and whether they had a non-parental supportive adult in their life. Parents reported on parent-teacher relationship quality. Confirmatory factor analyses supported a two-factor model (functional and relational support). Results psychometrically supported the ISS-YR. Scores demonstrated adequate internal consistency reliability. Results also supported the measure's convergent and criterion validity as evidenced by positive associations with school connectedness, academic efficacy, parental school involvement, and parent-teacher relationship quality. Youth with a supportive adult in their life at and outside of school had the highest ISS-YR scores. Implications of these findings for schools' efforts to support MC students are discussed.

Regular physical activity (PA) can reduce the risk of chronic diseases and improve cognitive function and emotional health. Unfortunately, many college students are inactive and at risk for chronic diseases and mental health conditions. Therefore, innovative exercise interventions that promote PA in this population are needed. PA adherence is enhanced when the experience promotes positive affect, and intrinsic factors drive participants. Zumba fitness is a popular group exercise class that provides a unique experience in which intrinsic motivation and positive affect are reinforced. This study aimed to implement and evaluate an online synchronous Zumba fitness course to promote PA among college students. Pre- and post-surveys assessed leisure-time PA, intrinsic motivation, and exercise affect. Also, participants (16 female students) reported affect state, need satisfaction, and enjoyment at the end of the Zumba session bi-weekly throughout the semester. Results indicated an overall positive trend from the start to the end of the semester and within individual Zumba sessions. Intrinsic motivation and exercise affect did not significantly increase, but self-reported MVPA increased significantly with a large effect size (d = 1.05). On the post-course evaluations, all students strongly agreed that they enjoyed the course and agreed or strongly agreed that it increased their motivation for physical activity. In addition, students reported enjoying the upbeat music, fun moves, and informative lectures. These findings suggest strategies other PA course instructors can adopt to provide enjoyable PA experiences and promote students' continued PA participation.

Tools that assess school supports for highly mobile, military-connected students are lacking. This study describes the development and preliminary validation of the Inventory of School Supports-Parent Report (ISS-PR). Participants were 433 parents (74% female; 62.5% White, 12% Black, 6.5% Asian, 5.5% Pacific Islander, 4% Native American, and 9.5% bi/multiracial; 19% Latinx) of students (grades 3-5) from families with an active-duty military parent. Parents completed the ISS-PR and rated: (a) how welcoming schools were toward military-connected families; (b) parent-teacher relationship quality; and (c) satisfaction with their child's school. We created three proportional index composite scores: a 26-item school supports score, a 13-item parent-focused supports score, and a 13-item child-focused supports score. Results supported the ISS-PR's psychometric properties: summary scores were positively linked to parent-teacher relationship quality, school welcoming, and parent satisfaction with the school. We also found evidence for test-retest reliability for parents completing the inventory with students who had either moved schools or remained in their previous schools. Future studies could use the ISS-PR to assess whether parents' perceptions of the availability and importance of school supports for military-connected families are related to other constructs such as overall school climate, student academic performance, and socioemotional functioning. Schools could use the inventory to determine which supports could potentially have the greatest impact for military-connected families and to what extent parents are aware of the supports schools offer.

This qualitative study highlights how children's literature can serve as a springboard for discussing current events while making connections with a similar historical event. Undergraduate students enrolled in children's literature courses read the graphic novel "Fever Year: The Killer Flu of 1918" and discussed the parallels between the book and the COVID-19 pandemic. Findings indicate strong text-to-self and text-to-world connections between the events of the flu of 1918 highlighted in the graphic novel and those of the COVID-19 pandemic. Connections included restrictions and closures, mask mandates, vaccine development, medical theories, and theories of spread. Information dissemination and consumption was a prominent theme.

This study assesses the impact of a 2-year virtual coaching program on teacher and student outcomes. The program - Feedback on Alignment and Support for Teachers (FAST) - was intended to deepen teachers' understanding of their state's standards and improve the alignment of their instruction with the standards. Relying on a multisite school-level randomized controlled trial, we assessed the impact of the FAST program in fourth-grade math and fifth-grade English language arts (ELA). We found that the program had a positive impact on the alignment of teachers' instruction with state standards for both math and ELA teachers (effect sizes = 0.70 and 0.40, respectively), although the impact was statistically significant only for math teachers. In contrast to a growing body of evidence on the benefits of instructional coaching, the program's impact on student achievement, was in the negative direction for both fourth-grade mathematics and fifth-grade ELA (effect sizes = -0.07 and -0.10, respectively), although the impact on achievement was statistically significant only for ELA. These results suggest that improving instructional alignment alone may not be sufficient for improving student achievement.

This study examined educators' descriptions of the positive character traits of students with autism spectrum disorder at ages 7-8 and 10-11, using an adapted version of the Values in Action (VIA) Classification of Strengths. The most commonly endorsed strengths at both age intervals were kindness, specific skills, self-regulation, and perseverance. Higher scores for challenging behavior were associated with a lower likelihood of endorsement for Happiness and Courage traits. Higher autism symptom severity scores were associated with a lower likelihood of endorsement for Courage traits. Few significant differences were found for endorsement of trait categories by students' educational placement or the type of curriculum they received. Results may have implications for student-teacher relationships, educational assessments, and school-based interventions that emphasize strengths and resilience.

The Saint Mary's University first-year student success program was developed by its strategic enrollment management (SEM) group to enhance support for first-year students. As an integrated program that implements student success modules into the first-year core curriculum, this initiative has proven to be effective in enhancing student engagement through the introduction of topics such as time management and effective study strategies (Tabvuma, et al. 2021). This article aims to raise awareness to both prospective social learning participants and higher education SEM-related leadership on the value that social learning approaches had in supporting the curriculum development and delivery of this unique campuswide first-year program initiative. As an ontological backdrop, the group utilized Wenger-Trayner and Wenger-Trayner's (2014) "Learning in a Landscape of Practice" framework as a reflective lens to offer unique perspectives on how members navigated three modes of identity (engagement, imagination, and alignment) throughout their shared practice, including strategies and challenges in such areas as student engagement, interdisciplinary meetings, and shared group activities. A discussion on achieving intended outcomes and challenges moving forward is offered as part of an evaluative self-analysis for this learning community and its implications on this first-year student success program initiative.

There is a public health epidemic in adolescents' use of Electronic Nicotine Delivery Systems (ENDSs), also known as electronic cigarettes, vaping products, or JUULs. However, little is known about the level of knowledge school staff have about ENDS. The purpose of this study is to examine outcomes of a nurse-led educational intervention designed to increase school staff knowledge about ENDS. A descriptive, nonrandomly selected pre-test/post-test design was used with 125 Wisconsin school staff. Results revealed further educational needs of school staff in content areas including advertising to youth and flavoring of ENDS. Following the educational intervention, post-test results showed a significant overall improvement in participant knowledge scores. Recommendations include implementing nurse-led education about ENDS to a more diverse population of school staff. Providing nurse-led ENDS education to school staff offers an upstream, proactive approach for school nurses to help address this public health epidemic.

Antarctic ice cores have been used to study the history of black carbon (BC), but little is known with regards to the physical and chemical characteristics of these particles in the remote atmosphere. Characterization remains limited by ultra-trace concentrations in ice core samples and the lack of adequate methods to isolate the particles unaltered from the melt water. To investigate the physical and chemical characteristics of these particles, we have developed a tangential flow filtration (TFF) method combined with transmission electron microscopy (TEM). Tests using ultrapure water and polystyrene latex particle standards resulted in excellent blanks and significant particle recovery. This approach has been applied to melt water from Antarctic ice cores as well as tropical rain from Darwin, Australia with successful results: TEM analysis revealed a variety of BC particle morphologies, insoluble coatings, and the attachment of BC to mineral dust particles. The TFF-based concentration of these particles has proven to give excellent results for TEM studies of BC particles in Antarctic ice cores and can be used for future studies of insoluble aerosols in rainwater and ice core samples.

This study investigates the effect of deglacial climate on the deposition of the solar proxy 10Be globally, and at two specific locations, the GRIP site at Summit, Central Greenland, and the Law Dome site in coastal Antarctica. The deglacial climate is represented by three 30 year time slice simulations of 10 000 BP (years before present = 1950 CE), 11 000 and 12 000 BP, compared with a preindustrial control simulation. The model used is the ECHAM5-HAM atmospheric aerosol–climate model, driven with sea-surface temperatures and sea ice cover simulated using the CSIRO Mk3L coupled climate system model. The focus is on isolating the 10Be production signal, driven by solar variability, from the weather- or climate-driven noise in the 10Be deposition flux during different stages of climate. The production signal varies at lower frequencies, dominated by the 11 year solar cycle within the 30 year timescale of these experiments. The climatic noise is of higher frequencies than 11 years during the 30 year period studied. We first apply empirical orthogonal function (EOF) analysis to global 10Be deposition on the annual scale and find that the first principal component, consisting of the spatial pattern of mean 10Be deposition and the temporally varying solar signal, explains 64% of the variability. The following principal components are closely related to those of precipitation. Then, we apply ensemble empirical decomposition (EEMD) analysis to the time series of 10Be deposition at GRIP and at Law Dome, which is an effective method for adaptively decomposing the time series into different frequency components. The low-frequency components and the long-term trend represent production and have reduced noise compared to the entire frequency spectrum of the deposition. The high-frequency components represent climate-driven noise related to the seasonal cycle of e.g. precipitation and are closely connected to high frequencies of precipitation. These results firstly show that the 10Be atmospheric production signal is preserved in the deposition flux to surface even during climates very different from today's both in global data and at two specific locations. Secondly, noise can be effectively reduced from 10Be deposition data by simply applying the EOF analysis in the case of a reasonably large number of available data sets, or by decomposing the individual data sets to filter out high-frequency fluctuations.

Seismic reflection soundings of ice thickness and seabed depth were acquired on the Larsen C Ice Shelf in order to test a sub-ice shelf bathymetry model derived from the inversion of IceBridge gravity data. A series of lines was collected, from the Churchill Peninsula in the north to the Joerg Peninsula in the south, and also towards the ice front. Sites were selected using the bathymetry model derived from the inversion of free-air gravity data to indicate key regions where sub-ice shelf oceanic circulation may be affected by ice draft and seabed depth. The seismic velocity profile in the upper 100 m of firn and ice was derived from shallow refraction surveys at a number of locations. Measured temperatures within the ice column and at the ice base were used to define the velocity profile through the remainder of the ice column. Seismic velocities in the water column were derived from previous in situ measurements. Uncertainties in ice and water cavity thickness are in general < 10 m. Compared with the seismic measurements, the root-mean-square error in the gravimetrically derived bathymetry at the seismic sites is 162 m. The seismic profiles prove the non-existence of several bathymetric features that are indicated in the gravity inversion model, significantly modifying the expected oceanic circulation beneath the ice shelf. Similar features have previously been shown to be highly significant in affecting basal melt rates predicted by ocean models. The discrepancies between the gravity inversion results and the seismic bathymetry are attributed to the assumption of uniform geology inherent in the gravity inversion process and also the sparsity of IceBridge flight lines. Results indicate that care must be taken when using bathymetry models derived by the inversion of free-air gravity anomalies. The bathymetry results presented here will be used to improve existing sub-ice shelf ocean circulation models.

Reconstruction of solar irradiance has only been possible for the Holocene so far. During the last deglaciation, two solar proxies (10Be and 14C) deviate strongly, both of them being influenced by climatic changes in a different way. This work addresses the climate influence on 10Be deposition by means of ECHAM5-HAM atmospheric aerosol–climate model simulations, forced by sea surface temperatures and sea ice extent created by the CSIRO Mk3L coupled climate system model. Three time slice simulations were performed during the last deglaciation: 10 000 BP ("10k"), 11 000 BP ("11k") and 12 000 BP ("12k"), each 30 yr long. The same, theoretical, 10Be production rate was used in each simulation to isolate the impact of climate on 10Be deposition. The changes are found to follow roughly the reduction in the greenhouse gas concentrations within the simulations. The 10k and 11k simulations produce a surface cooling which is symmetrically amplified in the 12k simulation. The precipitation rate is only slightly reduced at high latitudes, but there is a northward shift in the polar jet in the Northern Hemisphere, and the stratospheric westerly winds are significantly weakened. These changes occur where the sea ice change is largest in the deglaciation simulations. This leads to a longer residence time of 10Be in the stratosphere by 30 (10k and 11k) to 80 (12k) days, increasing the atmospheric concentrations (25–30% in 10k and 11k and 100% in 12k). Furthermore the shift of westerlies in the troposphere leads to an increase of tropospheric 10Be concentrations, especially at high latitudes. The contribution of dry deposition generally increases, but decreases where sea ice changes are largest. In total, the 10Be deposition rate changes by no more than 20% at mid- to high latitudes, but by up to 50% in the tropics. We conclude that on "long" time scales (a year to a few years), climatic influences on 10Be deposition remain small (less than 50%) even though atmospheric concentrations can vary significantly. Averaged over a longer period, all 10Be produced has to be deposited by mass conservation. This dominates over any climatic influences on 10Be deposition. Snow concentrations, however, do not follow mass conservation and can potentially be impacted more by climate due to precipitation changes. Quantifying the impact of deglacial climate modulation on 10Be in terms of preserving the solar signal locally is analysed in an accompanying paper (Heikkilä et al., 10Be in late deglacial climate simulated by ECHAM5-HAM – Part 2: Isolating the solar signal from 10Be deposition).

We present Bedmap2, a new suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60° S. We derived these products using data from a variety of sources, including many substantial surveys completed since the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously available and the improved data-coverage has in many areas revealed the full scale of mountain ranges, valleys, basins and troughs, only fragments of which were previously indicated in local surveys. The derived statistics for Bedmap2 show that the volume of ice contained in the Antarctic ice sheet (27 million km3) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6% greater, the mean depth of the bed beneath the grounded ice sheet is 72 m lower and the area of ice sheet grounded on bed below sea level is increased by 10%. The Bedmap2 compilation highlights several areas beneath the ice sheet where the bed elevation is substantially lower than the deepest bed indicated by Bedmap1. These products, along with grids of data coverage and uncertainty, provide new opportunities for detailed modelling of the past and future evolution of the Antarctic ice sheets.

Thorough pre-release studies to determine the environmental safety of biocontrol agents and to predict their effectiveness in controlling the target weed are crucial parts of any weed biocontrol project. Over the last five to six decades, the scientific rigor of pre-release investigations has constantly improved, reflected in a continuous decrease of nontarget attack incidences. Success rates have also increased, but are more variable, and the proportion of biocontrol agent releases leading to heavy impact has remained stagnant since the 1950 s at an approximate maximum of 25 %. In this paper, we review four methodological approaches that can further enhance environmental safety testing of weed biocontrol agents prior to release. These methodological approaches are (i) chemical ecology, (ii) predictability of field host use through relative performance analysis, (iii) quantification of field host range data, and (iv) experimental evolutionary studies. These approaches are not meant to substitute traditional host specificity testing, which remains the foundation of environmental safety assessments of weed biocontrol agents. Instead, they are meant to provide additional quantitative, behavioral, physiological and evolutionary insights to more accurately predict the realized host range of agents, and to further improve interpretation of host specificity data. We also review four methodological approaches that can facilitate increasing the effectiveness of weed biocontrol agents. These are (i) biocontrol agent and target weed trait analysis, (ii) experimental and field-based impact assessments, (iii) climate suitability studies, and (iv) target weed demography. The caveat of some of the tools and procedures is that they are context specific and not universally suitable for every weed biocontrol project. In addition, some of the approaches require substantial post-release data to corroborate their predictions. We are convinced that the tools and procedures reviewed here along with continued technological advances will refine predictions about the environmental safety and effectiveness of weed biocontrol agents. We also hope that this paper will motivate biocontrol scientists to not only adopt some of the tools more routinely, but ideally to improve them or to develop other novel methods outright. The more that analytical and explanatory research is conducted during weed biocontrol pre-release studies, the more credible the discipline will become.

Understanding the transport path of the solar activity proxy 10Be from source to archive is crucial for the interpretation of its observed variability. The extent of mixing of the strong production signal has been quantified in a previous study (Heikkilä et al., 2009). In this study we perform sensitivity studies to investigate the influence of model resolution on the degree of mixing and transport path of 10Be in the atmosphere using the ECHAM5-HAM aerosol-climate model. This study permits us to choose an acceptable resolution, and so minimum CPU time, to produce reconstructions as physically accurate as possible. Five model resolutions are applied: T21L19: a coarse horizontal and vertical resolution with model top at ca. 30 km, T42L31: an average horizontal and fine vertical one, T42L39: similar vertical resolution than L19 but including the middle atmosphere up to ca. 80 km, T63L31: a fine horizontal and vertical resolution and T63L47: a fine resolution horizontally and vertically with middle atmosphere. Comparison with observations suggests that a finer horizontal and vertical resolution might be beneficial, producing a reduced meridional gradient, although the spread between observations was much larger than between the five model runs. In terms of atmospheric mixing the differences became more distinguishable. All resolutions agreed that the main driver of deposition variability, observed in natural archives, is the input of stratospheric 10Be (total contribution 68%) which is transported into the troposphere at latitudes 30–50°. In the troposphere the model resolutions deviated largely in the dispersion of the stratospheric component over latitude. The finest resolution (T63L47) predicted the least dispersion towards low latitudes but the most towards the poles, whereas the coarsest resolution (T21L19) suggested the opposite. The tropospheric components of 10Be differed less between the five model runs. The largest differences were found in the polar tropospheric components, which contribute the least to total production (≈ 4%). We conclude that the use of the T42 horizontal resolution seems to be sufficient in terms of atmospheric mixing of a stratospheric tracer because no substantial improvement was seen when the resolution was increased from T42 to T63. The use of the middle atmospheric configuration is a trade-off between correctly describing stratospheric dynamics and having to reduce vertical resolution. The use of a high vertical resolution seemed more beneficial than the middle atmospheric configuration in this study. The differences found between the T42L31 and T63L31 resolutions were so small that T42L31 is a good choice because of its computational efficiency.