scholarly journals A global dataset of atmospheric <sup>7</sup>Be and <sup>210</sup>Pb measurements: annual air concentration and depositional flux

2021 ◽  
Vol 13 (6) ◽  
pp. 2963-2994
Author(s):  
Fule Zhang ◽  
Jinlong Wang ◽  
Mark Baskaran ◽  
Qiangqiang Zhong ◽  
Yali Wang ◽  
...  

Abstract. 7Be and 210Pb air concentration and depositional flux data provide key information on the origins and movements of air masses, as well as atmospheric deposition processes and residence time of aerosols. After their deposition onto the Earth's surface, they are utilized for tracing soil redistribution processes on land, particle dynamics in aquatic systems, and mixing processes in open ocean. Here we present a global dataset of air concentration and depositional flux measurements of atmospheric 7Be and 210Pb made by a large number of global research communities. Data were collected from published papers between 1955 and early 2020. It includes the annual surface air concentration data of 7Be from 367 sites and 210Pb from 270 sites, the annual depositional flux data of 7Be from 279 sites and 210Pb from 602 sites. When available, appropriate metadata have also been summarized, including geographic location, sampling date, methodology, annual precipitation, and references. The dataset is archived at https://doi.org/10.5281/zenodo.4785136 (Zhang et al., 2021) and is freely available for the scientific community. The purpose of this paper is to provide an overview of the scope and nature of this dataset and its potential utility as baseline data for future research.

2021 ◽  
Author(s):  
Fule Zhang ◽  
Jinlong Wang ◽  
Mark Baskaran ◽  
Qiangqiang Zhong ◽  
Yali Wang ◽  
...  

Abstract. 7Be and 210Pb air concentration and depositional flux data provide key information on the origins and movements of air masses, as well as deposition processes and residence time of aerosols. After their deposition onto the Earth's surface, they are utilized for tracing soil redistribution processes on land and particle dynamics and mixing processes in the ocean. Here we present a global dataset of air concentration and depositional flux measurements of atmospheric 7Be and 210Pb made by a large number of researchers and laboratories. Data were collected from published papers between 1955 and early 2020. It includes the annual surface air concentrations data of 7Be from 367 sites and of 210Pb from 270 sites, the annual depositional flux of 7Be from 279 sites, and of 210Pb from 602 sites. When available, appropriate metadata have also been summarized, including geographic location, sampling date, methodology, annual precipitation, and references. The dataset is available at https://doi.org/10.5281/zenodo.4521649 (Zhang et al., 2021). The purpose of this paper is to have the published data available in one place for future researchers' public consumption in their research and provide an overview of the scope and nature of this dataset holdings.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Karim Bouchlaghem ◽  
Blaise Nsom

This paper presents the evolution of Saharan dust advection when the PM10 (particles with an aerodynamic diameter below 10 μm) concentration exceeds standard limits in different Tunisian sites. Meteorological and concentration data (from 2004 to 2010) obtained from several monitoring stations and in situ measurements were used to identify African dust change in seasonal occurrence, their source origin, and their impact on surface PM10 concentrations. We pointed out that the Saharan dust contribution caused frequently the surpassing of the maximum number of days in excess of EU standard limits as well as of the maximum yearly average in the Mediterranean Tunisian coasts. The maximum daily concentration reaches 439 μg/m3during the Saharan events. The decrease in particulate levels recorded at the end of each event is due to the injection of European air masses and rainfalls. Primary pollutants peaks were much higher in winter than in summer which can be explained on the basis of the lower ventilation and mixing.


2017 ◽  
Vol 70 ◽  
pp. 142-151
Author(s):  
R.L. Roten ◽  
S.L. Post ◽  
A. Werner ◽  
M. Safa ◽  
A.J. Hewitt

The quantification of spray mass has historically been accomplished by means of fluorescent dyes and various string and ground samplers to capture the dye-laden spray. However, these methods are typically not used in close proximity to orchard sprayers and are prone to many sources of error. The objective of this study was to assess the ability of an in-field phase Doppler (pD) interferometer to quantify spray mass against two common string samplers. Measurements were taken at 0.5 m increments to 4.5 m vertically and 1.0 m increments to 5.0 m downwind from the spray. Converted flux measurements from the strings were compared with those obtained using the pD interferometer. The current pD technology was found to be incapable of collecting equivalent flux data to that obtained from the strings. However, the pD equipment did provide useful data on droplet velocity and size.


2021 ◽  
pp. 000313482110505
Author(s):  
Larissa Whitney ◽  
Kelly Bonneville ◽  
Madison Morgan ◽  
Lindsey L. Perea

Background Individuals presenting with traumatic injury in rural populations have significantly different injury patterns than those in urban environments. With an increasing Amish population, totaling over 33 000 in our catchment area, their unique way of life poses additional factors for injury. This study aims to evaluate differences in mechanism of injury, location of injury, and demographic patterns within the Amish population. We hypothesize that there will be an increased incidence of agriculture-related mechanisms of injury. Methods All Amish trauma patients presenting to our level I trauma center over 20 years (1/2000-4/2020) were retrospectively analyzed. Mechanism and geographic location of injury were collected. Demographic and clinical variables were compared between the age groups. Results There were 1740 patients included in the study with 36.4% (n = 634) ≤ 14 years. Only 10% (n = 174) were ≥ 65 years. The most common mechanism across all ages was falls. However, when separating out the pediatric population ( ≤ 14 years), 27.8% (n = 60) fell from a height on average > 8-10 feet. The most common geographic location of injury was at home in all age groups, except for the 15-24 year group, which was roadways. Discussion The Amish population poses a unique set of mechanisms of injury and thus injury patterns to rural trauma centers. We have found the most common injuries to be falls, buggy accidents, animal-related injuries, and farming accidents across all age groups. Future research and collaboration with other rural trauma centers treating large Amish populations would be beneficial to maximize injury prevention in this population. Level of Evidence Level 3a, epidemiological.


2021 ◽  
Author(s):  
Lukas Krasauskas ◽  
Jörn Ungermann ◽  
Peter Preusse ◽  
Felix Friedl-Vallon ◽  
Andreas Zahn ◽  
...  

&lt;p&gt;We present measurements of ozone, water vapour and nitric acid in the upper troposphere/lower stratosphere (UTLS) over North Atlantic and Europe. The measurements were acquired with the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) during the Wave Driven Isentropic Exchange (WISE) campaign in October 2017. GLORIA is an airborne limb imager capable of acquiring both 2-D data sets (curtains along the flight path) and, when the carrier aircraft is flying around the observed air mass, spatially highly resolved 3-D tomographic data. We show a case study of a Rossby wave (RW) breaking event observed during two subsequent flights two days apart. RW breaking is known to steepen tracer gradients and facilitate stratosphere-troposphere exchange (STE). Our measurements reveal complex spatial structures in stratospheric tracers (ozone and nitric acid) with multiple vertically stacked filaments. Backward trajectory analysis is used to demonstrate that these features are related to several previous Rossby wave breaking events and that the small-scale structure of the UTLS in the Rossby wave breaking region, which is otherwise very hard to observe, can be understood as stirring and mixing of air masses of tropospheric and stratospheric origin. It is also shown that a strong nitric acid enhancement observed just above the tropopause is likely a result of NO&lt;sub&gt;x&lt;/sub&gt; production by lightning activity. The measurements showed signatures of enhanced mixing between stratospheric and tropospheric air near the polar jet with some transport of water vapour into the stratosphere. Some of the air masses seen in 3-D data were encountered again two days later, stretched to very thin filament (horizontal thickness down to 30&amp;#8201;km at some altitudes) rich in stratospheric tracers. This repeated measurement allowed us to directly observe and analyse the progress of mixing processes in a thin filament over two days. Our results provide direct insight into small-scale dynamics of the UTLS in the Rossby wave breaking region, witch is of great importance to understanding STE and poleward transport in the UTLS.&lt;/p&gt;


2019 ◽  
Vol 34 (4) ◽  
pp. 665-689 ◽  
Author(s):  
James M. Crick ◽  
Dave Crick

Purpose Coopetition, namely, the interplay between cooperation and competition, has received a good deal of interest in the business-to-business marketing literature. Academics have operationalised the coopetition construct and have used these measures to test the antecedents and consequences of firms collaborating with their competitors. However, business-to-business marketing scholars have not developed and validated an agreed operationalisation that reflects the dimensionality of the coopetition construct. Thus, the purpose of this study is to develop and validate a multi-dimensional measure of coopetition for marketing scholars to use in future research. Design/methodology/approach To use a highly cooperative and highly competitive empirical context, sporting organisations in New Zealand were sampled, as the key informants within these entities engaged in different forms of coopetition. Checks were made to ensure that the sampled entities produced generalisable results. That is, it is anticipated that the results apply to other industries with firms engaging in similar business-to-business behaviours. Various sources of qualitative and quantitative data were acquired to develop and validate a multi-dimensional measure of coopetition (the COOP scale), which passed all major assessments of reliability and validity (including common method variance). Findings The results indicated that coopetition is a multi-dimensional construct, comprising three distinct dimensions. First, local-level coopetition is collaboration among competing entities within a close geographic proximity. Second, national-level coopetition is cooperation with rivals within the same country but across different geographic regions. Third, organisation-level coopetition is cooperation with competitors across different firms (including with indirect rivals), regardless of their geographic location and product markets served. Indeed, organisation-level coopetition extends to how companies engage in coopetition in domestic and international capacities, depending on the extent to which they compete in similar product markets in comparison to industry rivals. Also, multiple indicators were used to measure each facet of the coopetition construct after the scale purification stage. Originality/value Prior coopetition-based investigations have predominately been conceptual or qualitative in nature. The scarce number of existing scales have significant problems, such as not appreciating that coopetition is a multi-dimensional variable, as well as using single indicators. In spite of a recent call for research on the multiple levels of coopetition, there has not been an agreed measure of the construct that accounts for its multi-dimensionality. Hence, this investigation responds to such a call for research by developing and validating the COOP scale. Local-, national- and organisation-level coopetition are anticipated to be the main facets of the coopetition construct, which offer several avenues for future research.


2018 ◽  
Vol 26 (1) ◽  
pp. 82-92 ◽  
Author(s):  
James D. Ford ◽  
Nicole Couture ◽  
Trevor Bell ◽  
Dylan G. Clark

This paper identifies and characterizes current knowledge on climate change impacts, adaptation, and vulnerability for Canada’s northern coastline, outlining key research gaps. Warming temperatures and increased precipitation have been documented across the northern coast, with the rate of sea ice decline ranging from 2.9% to 10.4% per decade. Storm intensity and frequency is increasing, and permafrost is warming across the region. Many of these changes are projected to accelerate in the future, with in excess of 8 °C warming in winter possible under a high-emission scenario by 2081–2100. Vulnerability to these changes differs by region and community, a function of geographic location, nature of climate change impacts, and human factors. Capacity to manage climate change is high in some sectors, such as subsistence harvesting, but is being undermined by long-term societal changes. In other sectors, such as infrastructure and transportation, limitations in climate risk management capacity result in continuing high vulnerabilities. There is evidence that adaptation is taking place in response to experienced and projected impacts, although readiness for adaptation is challenged by limited resources, institutional capacity, and a need for support for adaptation across levels of government. Priority areas for future research include (i) expanding the sectoral and geographic focus of understanding on climate change impacts, adaptation, and vulnerability; (ii) integrating climatic and socio-economic projections into vulnerability and adaptation assessments; (iii) developing an evidence base on adaptation options; and (iv) monitoring and evaluating the effectiveness of adaptation support. Cross-cutting themes for advancing climate change impacts, adaptation, and vulnerability research on the north coast more broadly include the need for greater emphasis on interdisciplinary approaches and cross-cultural collaborations, support for decision-orientated research, and focus on effective knowledge mobilization.


Radiocarbon ◽  
2015 ◽  
Vol 57 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Laia Andreu-Hayles ◽  
Guaciara M Santos ◽  
David A Herrera-Ramírez ◽  
Javier Martin-Fernández ◽  
Daniel Ruiz-Carrascal ◽  
...  

This study used high-precision radiocarbon bomb-pulse dating of selected wood rings to provide an independent validation of the tree growth periodicity of Pseudolmedia rigida (Klotzsch & H. Karst) Cuatrec. from the Moraceae family, collected in the Madidi National Park in Bolivia. 14C content was measured by accelerator mass spectrometry (AMS) in 10 samples from a single tree covering over 70 yr from 1939 to 2011. These preliminary calendar dates were determined by dendrochronological techniques and were also used to select the samples for 14C AMS. In order to validate these preliminary dates using the established Southern Hemisphere (SH) 14C atmospheric concentration data set, the targeted rings were selected to be formed during periods before and after the 14C bomb spike nuclear tests (i.e. 1950s–1960s). The excellent agreement of the dendrochronological dates and the 14C signatures in tree rings associated with the same dates provided by the bomb-pulse 14C atmospheric values for the SH (SHCal zone 1–2) confirms the annual periodicity of the observed growth layers, and thus the high potential of this species for tree-ring analysis. The lack of discrepancies between both data sets also suggests that there are no significant latitudinal differences between the 14C SHCal zone 1–2 curve and the 14C values obtained from the selected tree rings at this geographic location (14°33′S, 68°49′W) in South America. The annual resolution of P. rigida tree rings opens the possibility of broader applications of dendrochronological analysis for ecological and paleoclimatic studies in the Bolivian tropics, as well as the possibility of using wood samples from some tree species from this region to improve the quality of the bomb-pulse 14C SHCal curve at this latitude.


2016 ◽  
Vol 13 (10) ◽  
pp. 1042-1048 ◽  
Author(s):  
Jill A. Nolan ◽  
Christa L. Lilly ◽  
Janie M. Leary ◽  
Wesley Meeteer ◽  
Hugh D. Campbell ◽  
...  

Background:Parent support for child physical activity is a consistent predictor of increased childhood activity. Little is known about factors that prevent or facilitate support. The purpose of this research was to identify barriers to parent support for child physical activity in Appalachian parents.Methods:A cross-sectional study assessed parents whose children participated in Coronary Artery Risk Detection in Appalachian Communities (CARDIAC) screenings in a rural Appalachian state. Barriers to parental support for physical activity, demographics, geographic location, and parental support for activity were measured.Results:A total of 475 parents completed surveys. The majority were mothers (86.7%), parents of kindergarteners (49.5%), white (89.3%), and living in a nonrural area (70.5%). Community-level factors were most frequently cited as barriers, particularly those related to the built environment. Rural and low-income parents reported significantly higher barriers. Community, interpersonal, and intrapersonal barriers were negatively correlated with parent support for child physical activity. Parents of girls reported a higher percentage of barriers related to safety.Conclusions:Reported barriers in this sample differed from those reported elsewhere (Davison, 2009). Specific groups such as low-income and rural parents should be targeted in intervention efforts. Future research should explore gender differences in reported barriers to determine the influence of cultural stereotypes.


2011 ◽  
Vol 50 (11) ◽  
pp. 2210-2222 ◽  
Author(s):  
John P. Gallagher ◽  
Ian G. McKendry ◽  
Anne Marie Macdonald ◽  
W. Richard Leaitch

AbstractA mountain air chemistry observatory has been operational on the summit of Whistler Mountain in British Columbia, Canada, since 2002. A 1-yr dataset of condensation nuclei (CN) concentration from this site has been analyzed along with corresponding meteorological data to assess the frequency and patterns of influence from the planetary boundary layer (PBL). Characterization of air masses sampled from the site as either PBL influenced or representative of the free troposphere (FT) is important to subsequent analysis of the chemistry data. Median CN concentrations and seasonal trends were found to be comparable to other midlatitude mountain sites. Monthly median number concentrations ranged from 120 cm−3 in January to 1601 cm−3 in July. Using well-defined diurnal cycles in CN concentration as an indicator of air arriving from nearby valleys, PBL influence was found to occur on a majority of days during spring and summer and less frequently in late autumn and winter. Days with PBL influence were usually associated with synoptic-scale weather patterns that were conducive to convective mixing processes. Although more common in the warm season, vertical mixing capable of transporting valley air to the mountaintop also occurred in February during a period of high pressure aloft. In contrast, an August case study indicated that the more stable character of marine air masses can at times keep the PBL below the summit on summer days. Considerable variability in the synoptic-scale weather conditions at Whistler means that careful analysis of available datasets must be made to discriminate FT from PBL periods at the observatory.


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