A compilation of tropospheric measurements of gas-phase and aerosol chemistry in polar regions

Sander, R.; Bottenheim, J. W.

doi:10.5194/essd-4-215-2012

Cited by 17 publications

(16 citation statements)

References 423 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On all other days, lower wind speeds were measured at the sampling site ranging between 0.27 m/s and 5.88 m/s and a mean value of 1.70 m/s. The mean NO and NO 2 concentrations over the entire campaign were in agreement with previous measurements in the coastal Arctic boundary layer (Beine et al 1996, 1997a, b, 2001a, 2002aAmoroso et al 2010;Sander and Bottenheim 2012). Statistically significant diurnal cycles of NO and NO 2 were observed on some days (9)(10)(11)(15)(16)(21)(22)(23)(24)(25)(26)(27) and appeared more or less symmetric with UV radiation.…”

Section: Snow Sampling and Analysissupporting

confidence: 82%

Air-snow exchange of reactive nitrogen species at Ny-Ålesund, Svalbard (Arctic)

Ianniello

Spataro

Salvatori

et al. 2016

Rend. Fis. Acc. Lincei

View full text Add to dashboard Cite

Measurements of atmospheric concentrations and fluxes of reactive nitrogen (NO, NO 2 , HNO 3 , NO 3 -fine and NO 3 -coarse ) above the snow surface were performed from 29 March to 30 April 2010 at Ny-Å lesund, Svalbard.Determinations of chemical and physical properties of snow were also carried out. Both NO and NO 2 showed clear diurnal cycles with noontime maxima and nighttime minima. Significant emission fluxes of NO and NO 2 were observed, reaching noontime values up to 19.42 and 25.20 pmol/m 2 s, respectively. The snow surface was the source of NO and NO 2 but these observed releases were small due to almost alkaline snow environment and chemical forms of snow NO 3 -. Significant deposition fluxes of HNO 3 , fine and coarse particulate NO 3 -fluxes were also observed, reaching peak values up to -18.00, -37.80 and -12.50 pmol/m 2 s, respectively, during snowfall events. Measurements of surface snow provided experimental data that the total contribution of dry deposition of these species to the NO 3 --N in the snow was about 24 %. However, wet deposition in falling snow seemed to be the major contribution to the nitrate input to the snow.

show abstract

Section: Snow Sampling and Analysissupporting

confidence: 82%

Air-snow exchange of reactive nitrogen species at Ny-Ålesund, Svalbard (Arctic)

Ianniello

Spataro

Salvatori

et al. 2016

Rend. Fis. Acc. Lincei

View full text Add to dashboard Cite

show abstract

“…The flux measurements revealed both emissions and deposition fluxes of all the investigated compounds (NO, NO 2 , HNO 3 − , and p‐NO 3 − , Figures and ) and where the mean NO and NO 2 concentrations were in agreement with other measurements in the coastal Arctic boundary layer during the same time of year [ Allegrini et al ., ; Beine et al ., , ; Amoroso et al ., ; Sander and Bottenheim , ]. Although the calculated daily NO and NO 2 fluxes (Figure ) are in the lower region of what has earlier been reported for Ny‐Ålesund by Amoroso et al .…”

Section: Discussionmentioning

confidence: 58%

Nitrate postdeposition processes in Svalbard surface snow

et al. 2014

View full text Add to dashboard Cite

The snowpack acts as a sink for atmospheric reactive nitrogen, but several postdeposition pathways have been reported to alter the concentration and isotopic composition of snow nitrate with implications for atmospheric boundary layer chemistry, ice core records, and terrestrial ecology following snow melt. Careful daily sampling of surface snow during winter (11-15 February 2010) and springtime (9 April to 5 May 2010) near Ny-Ålesund, Svalbard reveals a complex pattern of processes within the snowpack. Dry deposition was found to dominate over postdeposition losses, with a net nitrate deposition rate of (0.6 ± 0.2) μmol m À2 d À1 to homogeneous surface snow. At Ny-Ålesund, such surface dry deposition can either solely result from long-range atmospheric transport of oxidized nitrogen or include the redeposition of photolytic/bacterial emission originating from deeper snow layers. Our data further confirm that polar basin air masses bring 15 N-depleted nitrate to Svalbard, while high nitrate δ( 18 O) values only occur in connection with ozone-depleted air, and show that these signatures are reflected in the deposited nitrate. Such ozone-depleted air is attributed to active halogen chemistry in the air masses advected to the site. However, here the Ny-Ålesund surface snow was shown to have an active role in the halogen dynamics for this region, as indicated by declining bromide concentrations and increasing nitrate δ( 18 O), during high BrO (low-ozone) events. The data also indicate that the snowpack BrO-NO x cycling continued in postevent periods, when ambient ozone and BrO levels recovered.

show abstract

“…The model includes (i) gas-phase chemistry (Atkinson et al, 2006;Burkholder et al, 2015;Orlando & Burkholder, 2000;Thompson et al, 2015); (ii) photolysis reactions, with j values calculated using the NCAR Tropospheric Ultraviolet and Visible Radiation Model (https://www2.acom.ucar.edu/modeling/troposphericultraviolet-and-visible-tuv-radiation-model); (iii) heterogeneous reactions on both aerosol particles and snow grains in the surface snow layer (Ammann et al, 2013;Deiber et al, 2004;Hu et al, 1995;Sander & Bottenheim, 2012); (iv) aqueous-phase reactions in both deliquescent particles and a liquid-like layer on snow grains in the surface snow layer (following Beckwith et al, 1996;Liu & Margerum, 2001;Oum et al, 1998;Thomas et al, 2011;Toyota et al, 2014;Wang & Margerum, 1994); (v) dry deposition of trace gases (Wesely, 1989); and (vi) prescribed snowpack trace gas emissions. Gas-phase, photolysis, heterogeneous, and aqueous-phase reactions involving chlorine and bromine species are summarized in Tables S2-S5.…”

Section: Model Descriptionmentioning

confidence: 99%

Molecular Halogens Above the Arctic Snowpack: Emissions, Diurnal Variations, and Recycling Mechanisms

Wang

Pratt

2017

JGR Atmospheres

View full text Add to dashboard Cite

Elevated levels of reactive bromine and chlorine species in the springtime Arctic boundary layer contribute to ozone depletion and mercury oxidation, as well as reactions with volatile organic compounds. Recent laboratory and field studies have revealed that snowpack photochemistry leads to Br2 and Cl2 production, the mechanisms of which remain poorly understood. In this work, we use a photochemical box model, with a simplified snow module, to examine the halogen chemistry occurring during the March 2012 Bromine, Ozone, and Mercury Experiment (BROMEX) near Utqiaġvik (Barrow), Alaska. Elevated daytime Br2 levels (e.g., 6–30 parts per trillion (ppt) at around local noon) reported in previous studies and in this work may be explained by Br + BrNO2/BrONO2 reactions under conditions of depleted O3 (<~10 ppb) and background NO2 (10–100 ppt). Even at low background NOx levels at Utqiaġvik, ClONO2 is predicted to be important in the production of Cl2 via multiphase reaction with Cl−. In the late afternoon, photolysis alone cannot explain the rapid decrease of Cl2 observed in the Arctic boundary layer. Heterogeneous reactions of Cl2 on aerosol particles and surface snowpack are suggested to play a key role in atmospheric Cl2 removal and possible BrCl production. Given the importance of the snowpack in the multiphase chemistry of the Arctic boundary layer, future measurements should focus on vertically resolved measurements of NOx and reactive halogens, as well as simultaneous particulate and snow halide measurements, to further evaluate and isolate the halogen production and vertical propagation mechanisms through one‐dimensional modeling.

show abstract

A compilation of tropospheric measurements of gas-phase and aerosol chemistry in polar regions

Cited by 17 publications

References 423 publications

Air-snow exchange of reactive nitrogen species at Ny-Ålesund, Svalbard (Arctic)

Air-snow exchange of reactive nitrogen species at Ny-Ålesund, Svalbard (Arctic)

Nitrate postdeposition processes in Svalbard surface snow

Molecular Halogens Above the Arctic Snowpack: Emissions, Diurnal Variations, and Recycling Mechanisms

Contact Info

Product

Resources

About