Characterising terrestrial influences on Antarctic air masses using Radon-222 measurements at King George Island

Chambers, Scott D.; Hong, Sang-Bum; Williams, Alastair G.; Crawford, Jagoda; Griffiths, Alan D.; Park, Sang Jong

doi:10.5194/acp-14-9903-2014

Cited by 66 publications

(58 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to measure radon concentrations, a 700 L dual-flowloop two-filter radon detector, designed and built by the Australian Nuclear Science and Technology Organisation (Whittlestone and Zahorowski, 1998;Chambers et al, 2014), was installed at ATARS in 2011 and has been fully operational since July 2012. The detector provided continuous hourly radon concentrations for the duration of the SAFIRED campaign, sampling air at 40 L min −1 from 12 m above ground level through 25 mm high-density polyethylene agricultural pipe.…”

Section: Radonmentioning

confidence: 99%

Biomass burning emissions in north Australia during the early dry season: an overview of the 2014 SAFIRED campaign

et al. 2017

Self Cite

View full text Add to dashboard Cite

Abstract. The SAFIRED (Savannah Fires in the Early Dry Season) campaign took place from 29 May until 30 June 2014 at the Australian Tropical Atmospheric Research Station (ATARS) in the Northern Territory, Australia. The purpose of this campaign was to investigate emissions from fires in the early dry season in northern Australia. Measurements were made of biomass burning aerosols, volatile organic compounds, polycyclic aromatic carbons, greenhouse gases, radon, speciated atmospheric mercury and trace metals. Aspects of the biomass burning aerosol emissions investigated included; emission factors of various species, physical and chemical aerosol properties, aerosol aging, micronutrient supply to the ocean, nucleation, and aerosol water uptake. Over the course of the month-long campaign, biomass burning signals were prevalent and emissions from several large single burning events were observed at ATARS.Biomass burning emissions dominated the gas and aerosol concentrations in this region. Dry season fires are extremely frequent and widespread across the northern region of Australia, which suggests that the measured aerosol and gaseous emissions at ATARS are likely representative of signals across the entire region of north Australia. Air mass forward trajectories show that these biomass burning emissions are carried north-west over the Timor Sea and could influence the atmosphere over Indonesia and the tropical atmosphere over the Indian Ocean. Here we present characteristics of the biomass burning observed at the sampling site and provide an overview of the more specific outcomes of the SAFIRED campaign.

show abstract

Section: Radonmentioning

confidence: 99%

Biomass burning emissions in north Australia during the early dry season: an overview of the 2014 SAFIRED campaign

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Whittlestone and Zahorowski, 1998;Chambers et al, 2014). Raw counts and detector operational parameters were logged at half-hourly intervals to a CR800 logger (Campbell Scientific, Inc.) and integrated to hourly values for post processing.…”

Section: Site and Observationsmentioning

confidence: 99%

On the use of radon for quantifying the effects of atmospheric stability on urban emissions

et al. 2015

Self Cite

View full text Add to dashboard Cite

Abstract.Radon is increasingly being used as a tool for quantifying stability influences on urban pollutant concentrations. Bulk radon gradients are ideal for this purpose, since the vertical differencing substantially removes contributions from processes on timescales greater than diurnal and (assuming a constant radon source) gradients are directly related to the intensity of nocturnal mixing. More commonly, however, radon measurements are available only at a single height. In this study we argue that single-height radon observations should not be used quantitatively as an indicator of atmospheric stability without prior conditioning of the time series to remove contributions from larger-scale "nonlocal" processes. We outline a simple technique to obtain an approximation of the diurnal radon gradient signal from a single-height measurement time series, and use it to derive a four category classification scheme for atmospheric stability on a "whole night" basis. A selection of climatological and pollution observations in the Sydney region are then subdivided according to the radon-based scheme on an annual and seasonal basis. We compare the radon-based scheme against a commonly used Pasquill-Gifford (P-G) type stability classification and reveal that the most stable category in the P-G scheme is less selective of the strongly stable nights than the radon-based scheme; this lead to significant underestimation of pollutant concentrations on the most stable nights by the P-G scheme. Lastly, we applied the radon-based classification scheme to mixing height estimates calculated from the diurnal radon accumulation time series, which provided insight to the range of nocturnal mixing depths expected at the site for each of the stability classes.

show abstract

“…Whittlestone and Zahorowski, 1998;Chambers et al, 2014 was removed from the sampled air stream. The detector has a response time (time to half-peak magnitude) of 45 min, which was partially accounted for in post processing by the Fig.…”

Section: Site and Observationsmentioning

confidence: 99%

Radon as a tracer of atmospheric influences on traffic-related air pollution in a small inland city

Williams¹,

Chambers²,

Conen³

et al. 2016

Tellus B: Chemical and Physical Meteorology

View full text Add to dashboard Cite

A B S T R A C T One year of radon, benzene and carbon monoxide (CO) concentrations were analysed to characterise the combined influences of variations in traffic density and meteorological conditions on urban air quality in Bern, Switzerland. A recently developed radon-based stability categorisation technique was adapted to account for seasonal changes in day length and reduction in the local radon flux due to snow/ice cover and high soil moisture. Diurnal pollutant cycles were shown to result from an interplay between variations in surface emissions (traffic density), the depth of the nocturnal atmospheric mixing layer (dilution) and local horizontal advection of cleaner air from outside the central urban/industrial area of this small compact inland city. Substantial seasonal differences in the timing and duration of peak pollutant concentrations in the diurnal cycle were attributable to changes in day length and the switching to/from daylight-savings time in relation to traffic patterns. In summer, average peak benzene concentrations (0.62 ppb) occurred in the morning and remained above 0.5 ppb for 2 hours, whereas in winter average peak concentrations (0.85 ppb) occurred in the evening and remained above 0.5 ppb for 9 hours. Under stable conditions in winter, average peak benzene concentrations (1.1 ppb) were 120% higher than for well-mixed conditions (0.5 ppb). By comparison, summertime peak benzene concentrations increased by 53% from well-mixed (0.45 ppb) to stable nocturnal conditions (0.7 ppb). An idealised box model incorporating a simple advection term was used to derive a nocturnal mixing length scale based on radon, and then inverted to simulate diurnal benzene and CO emission variations at the city centre. This method effectively removes the influences of local horizontal advection and stability-related vertical dilution from the emissions signal, enabling a direct comparison with hourly traffic density. With the advection term calibrated appropriately, excellent results were obtained, with high regression coefficients in spring and summer for both benzene (r 2 Â0.90Á0.96) and CO (r 2 Â0.88Á0.98) in the two highest stability categories. Weaker regressions in winter likely indicate additional contributions from combustion sources unrelated to vehicular emissions. Average vehicular emissions during daylight hours were estimated to be around 0.503 (542) kg km (2 h (1 for benzene (CO) in the Bern city centre.

show abstract

Characterising terrestrial influences on Antarctic air masses using Radon-222 measurements at King George Island

Cited by 66 publications

References 50 publications

Biomass burning emissions in north Australia during the early dry season: an overview of the 2014 SAFIRED campaign

Biomass burning emissions in north Australia during the early dry season: an overview of the 2014 SAFIRED campaign

On the use of radon for quantifying the effects of atmospheric stability on urban emissions

Radon as a tracer of atmospheric influences on traffic-related air pollution in a small inland city

Contact Info

Product

Resources

About