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Author Elena Barbaro, Krystyna Koziol, Mats P. Björkman, Carmen P. Vega, Christian Zdanowicz, Tonu Martma, Jean-Charles Gallet, Daniel Kępski, Catherine Larose, Bartłomiej Luks, Florian Tolle, Thomas V. Schuler, Aleksander Uszczyk, Andrea Spolaor doi  isbn
openurl 
  Title Measurement report: Spatial variations in ionic chemistry and water-stable isotopes in the snowpack on glaciers across Svalbard during the 2015–2016 snow accumulation season Type Journal
  Year 2021 Publication Atmospheric Chemistry and Physics Abbreviated Journal  
  Volume 21 Issue 4 Pages 3163-3180  
  Keywords  
  Abstract The Svalbard archipelago, located at the Arctic sea-ice edge between 74 and 81∘ N, is ∼60 % covered by glaciers. The region experiences rapid variations in atmospheric flow during the snow season (from late September to May) and can be affected by air advected from both lower and higher latitudes, which likely impact the chemical composition of snowfall. While long-term changes in Svalbard snow chemistry have been documented in ice cores drilled from two high-elevation glaciers, the spatial variability of the snowpack composition across Svalbard is comparatively poorly understood. Here, we report the results of the most comprehensive seasonal snow chemistry survey to date, carried out in April 2016 across 22 sites on seven glaciers across the archipelago. At each glacier, three snowpits were sampled along the altitudinal profiles and the collected samples were analysed for major ions (Ca2+, K+, Na+, Mg2+, NH4+, SO42-, Br−, Cl−, and NO3-) and stable water isotopes (δ18O, δ2H). The main aims were to investigate the natural and anthropogenic processes influencing the snowpack and to better understand the influence of atmospheric aerosol transport and deposition patterns on the snow chemical composition. The snow deposited in the southern region of Svalbard is characterized by the highest total ionic loads, mainly attributed to sea-salt particles. Both NO3- and NH4+ in the seasonal snowpack reflect secondary aerosol formation and post-depositional changes, resulting in very different spatial deposition patterns: NO3- has its highest loading in north-western Spitsbergen and NH4+ in the south-west. The Br− enrichment in snow is highest in north-eastern glacier sites closest to areas of extensive sea-ice coverage. Spatial correlation patterns between Na+ and δ18O suggest that the influence of long-range transport of aerosols on snow chemistry is proportionally greater above 600–700 m a.s.l.  
  Programme 1192  
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  ISSN 1680-7316 ISBN 1680-7316 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8608  
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Author Christian Zdanowicz, Jean-Charles Gallet, Mats P. Björkman, Catherine Larose, Thomas Schuler, Bartłomiej Luks, Krystyna Koziol, Andrea Spolaor, Elena Barbaro, Tõnu Martma, Ward van Pelt, Ulla Wideqvist, Johan Ström doi  openurl
  Title Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018 Type Journal
  Year 2021 Publication Atmospheric Chemistry and Physics Abbreviated Journal  
  Volume 21 Issue 4 Pages 3035-3057  
  Keywords  
  Abstract Light-absorbing carbonaceous aerosols emitted by biomass or fossil fuel combustion can contribute to amplifying Arctic climate warming by lowering the albedo of snow. The Svalbard archipelago, being near to Europe and Russia, is particularly affected by these pollutants, and improved knowledge of their distribution in snow is needed to assess their impact. Here we present and synthesize new data obtained on Svalbard between 2007 and 2018, comprising measurements of elemental (EC) and water-insoluble organic carbon (WIOC) in snow from 37 separate sites. We used these data, combined with meteorological data and snowpack modeling, to investigate the variability of EC and WIOC deposition in Svalbard snow across latitude, longitude, elevation and time. Overall, EC concentrations (CsnowEC) ranged from <1.0 to 266.6 ng g−1, while WIOC concentrations (CsnowWIOC) ranged from <1 to 9426 ng g−1, with the highest values observed near Ny-Ålesund. Calculated snowpack loadings (LsnowEC, LsnowWIOC) on glaciers surveyed in spring 2016 were 0.1 to 2.6 mg m−2 and 2 to 173 mg m−2, respectively. The median CsnowEC and the LsnowEC on those glaciers were close to or lower than those found in earlier (2007–2009), comparable surveys. Both LsnowEC and LsnowWIOC increased with elevation and snow accumulation, with dry deposition likely playing a minor role. Estimated area-averaged snowpack loads across Svalbard were 1.1 mg EC m−2 and 38.3 mg WIOC m−2 for the 2015–2016 winter. An ∼11-year long dataset of spring surface snow measurements from the central Brøgger Peninsula was used to quantify the interannual variability of EC and WIOC deposition in snow. In most years, CsnowEC and CsnowWIOC at Ny-Ålesund (50 m a.s.l.) were 2–5 times higher than on the nearby Austre Brøggerbreen glacier (456 m a.s.l.), and the median EC/WIOC in Ny-Ålesund was 6 times higher, suggesting a possible influence of local EC emission from Ny-Ålesund. While no long-term trends between 2011 and 2018 were found, CsnowEC and CsnowWIOC showed synchronous variations at Ny-Ålesund and Austre Brøggerbreen. When compared with data from other circum-Arctic sites obtained by comparable methods, the median CsnowEC on Svalbard falls between that found in central Greenland (lowest) and those in continental sectors of European Arctic (northern Scandinavia, Russia and Siberia; highest), which is consistent with large-scale patterns of BC in snow reported by surveys based on other methods.  
  Programme 1192  
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  ISSN 1680-7316 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8604  
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Author Philippe Ricaud, Massimo Del Guasta, Angelo Lupi, Romain Roehrig, Eric Bazile, Pierre Durand, Jean-Luc Attié, Alessia Nicosia, Paolo Grigioni doi  openurl
  Title Supercooled liquid water clouds observed over Dome C, Antarctica: temperature sensitivity and surface radiation impact Type Journal
  Year 2022 Publication Atmospheric Chemistry and Physics Discussions Abbreviated Journal  
  Volume Issue Pages 1-38  
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  Abstract

Abstract. Clouds affect the Earth climate with an impact that depends on the cloud nature (solid/ liquid water). Although the Antarctic climate is changing rapidly, cloud observations are sparse over Antarctica due to few ground stations and satellite observations. The Concordia station is located on the East Antarctic Plateau (75° S, 123° E, 3233 m above mean sea level), one of the driest and coldest places on Earth. We used observations of clouds, temperature, liquid water and surface radiation performed at Concordia during 4 austral summers (December 2018–2021) to analyze the link between liquid water and temperature and its impact on surface radiation in the presence of supercooled liquid water (liquid water for temperature less than 0 °C) clouds (SLWCs). Our analysis shows that, within SLWCs, temperature logarithmically increases from -36.0 °C to -16.0 °C when liquid water path increases from 1.0 to 14.0 g m-2, and SLWCs positively impact the net surface radiation, which logarithmically increases by 0.0 to 50.0 W m-2 when liquid water path increases from 1.7 to 3.0 g m-2. We finally estimate that SLWCs have a great potential radiative impact over Antarctica whatever the season considered, up to 5.0 W m-2 over the Eastern Antarctic Plateau and up to 30 W m-2 over the Antarctic Peninsula in summer.

 
  Programme 910  
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  Notes Approved yes  
  Call Number Serial 8652  
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Author Ricaud, P., E. Bazile, M. del Guasta, C. Lanconelli, P. Grigioni, and A. Mahjoub doi  openurl
  Title Genesis of Diamond Dust and Thick Cloud Episodes observed above Dome C, Antarctica Type Journal Article
  Year 2016 Publication ATMOSPHERIC CHEMISTRY AND PHYSICS Abbreviated Journal  
  Volume 2016 Issue Pages 1-54  
  Keywords  
  Abstract From 15 March to 8 April 2011 and from 4 to 5 March 2013, the atmosphere above Dome C (Concordia station, Antarctica, 75°06' S, 123°21' E, 3233 m amsl) has been probed by several instruments and model to study episodes of thick cloud and diamond dust (cloud constituted of suspended ice crystals). 1) A ground-based microwave radiometer (HAMSTRAD, H2O Antarctica Microwave Stratospheric and Tropospheric Radiometers) installed at Dome C that provided vertical profiles of tropospheric temperature and absolute humidity to calculate Integrated Water Vapour (IWV). 2) Daily radiosoundings launched at 12:00 UTC at Dome C. 3) A tropospheric aerosol Lidar that provides aerosol depolarization ratio along the vertical at Dome C. 4) Down- and upward short- and longwave radiations as provided by the Baseline Surface Radiation Network (BSRN) facilities. 5) Space-borne aerosol depolarization ratio from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) Lidar aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) platform along orbits close to the Dome C station. The time evolution of the atmosphere has also been evaluated by considering the outputs from the meso-scale AROME and the global-scale ARPEGE meteorological models. Two distinct periods are highlighted by all the datasets: the warm and wet periods (24–26 March 2011 and 4 March 2013) and the cold and dry periods (5 April 2011 and 5 March 2013). Combining radiation and active measurements of aerosols with nebulosity calculations, a thick cloud is detected during the warm and wet periods with high depolarization ratios (greater than 30 %) from the surface to 5–7 km altitude associated with precipitation of ice particles and the presence of a supercooled liquid water (depolarization of about 10 %) cloud. During the cold and dry periods, high depolarization ratios (greater than 30 %) to a maximum altitude of 100–500 m are measured suggesting that the cloud is constituted of ice crystals with no trace of precipitation. These ice crystals in suspension in the air are named diamond dust. Considering 5-day back trajectories from Dome C and global distributions of IWV over the Antarctic show that the thick-cloud episode is attributed to air masses with an oceanic origin whilst the diamond dust episode is attributed to air masses with continental origins. This is consistent with ARPEGE temperature and water vapour tendency favouring predominantly advection processes including microphysical processes for water vapour.  
  Programme 910  
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  ISSN 1680-7316 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6445  
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Author J. Bock, J. Savarino, and G. Picard doi  openurl
  Title Air – snow exchange of nitrate: a modelling approach to investigate physicochemical processes in surface snow at Dome C, Antarctica Type Journal Article
  Year 2016 Publication ATMOSPHERIC CHEMISTRY AND PHYSICS Abbreviated Journal  
  Volume 16 Issue 19 Pages 12531-12550  
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  Programme 1110  
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  Series Editor Series Title Abbreviated Series Title  
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  ISSN 1680-7316 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6430  
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Author Steven Compernolle, Tijl Verhoelst, Gaia Pinardi, José Granville, Daan Hubert, Arno Keppens, Sander Niemeijer, Bruno Rino, Alkis Bais, Steffen Beirle, Folkert Boersma, John P. Burrows, Isabelle De Smedt, Henk Eskes, Florence Goutail, François Hendrick, Alba Lorente, Andrea Pazmino, Ankie Piters, Enno Peters, Jean-Pierre Pommereau, Julia Remmers, Andreas Richter, Jos van Geffen, Michel Van Roozendael, Thomas Wagner, Jean-Christopher Lambert doi  openurl
  Title Validation of Aura-OMI QA4ECV NO2 climate data records with ground-based DOAS networks: the role of measurement and comparison uncertainties Type Journal
  Year 2020 Publication Atmospheric Chemistry and Physics Abbreviated Journal  
  Volume 20 Issue 13 Pages 8017-8045  
  Keywords  
  Abstract The Qa4ecv (Quality Assurance For Essential Climate Variables) Version 1.1 Stratospheric And Tropospheric No2 Vertical Column Density (Vcd) Climate Data Records (Cdrs) From The Omi (Ozone Monitoring Instrument) Satellite Sensor Are Validated Using Ndacc (Network For The Detection Of Atmospheric Composition Change) Zenith-scattered Light Differential Optical Absorption Spectroscopy (Zsl-doas) And Multi-axis Doas (Max-doas) Data As A Reference. The Qa4ecv Omi Stratospheric Vcds Have A Small Bias Of ∼0.2 Pmolec.cm-2 (5 %–10 %) And A Dispersion Of 0.2 To 1 Pmolec.cm-2 With Respect To The Zsl-doas Measurements. Qa4ecv Tropospheric Vcd Observations From Omi Are Restricted To Near-cloud-free Scenes, Leading To A Negative Sampling Bias (With Respect To The Unrestricted Scene Ensemble) Of A Few Peta Molecules Per Square Centimetre (Pmolec.cm-2) Up To −10 Pmolec.cm-2 (−40 %) In One Extreme High-pollution Case. The Qa4ecv Omi Tropospheric Vcd Has A Negative Bias With Respect To The Max-doas Data (−1 To −4 Pmolec.cm-2), Which Is A Feature Also Found For The Omi Omno2 Standard Data Product. The Tropospheric Vcd Discrepancies Between Satellite Measurements And Ground-based Data Greatly Exceed The Combined Measurement Uncertainties. Depending On The Site, Part Of The Discrepancy Can Be Attributed To A Combination Of Comparison Errors (Notably Horizontal Smoothing Difference Error), Measurement/retrieval Errors Related To Clouds And Aerosols, And The Difference In Vertical Smoothing And A Priori Profile Assumptions.  
  Programme 209  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1680-7316 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8014  
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Author C. Genthon, L. Piard, E. Vignon, J.-B. Madeleine, M. Casado, H. Gallée doi  isbn
openurl 
  Title Atmospheric moisture supersaturation in the near-surface atmosphere at Dome C, Antarctic Plateau Type Journal
  Year 2017 Publication Atmos. chem. phys. Abbreviated Journal  
  Volume 17 Issue 1 Pages 691-704  
  Keywords  
  Abstract Supersaturation often occurs at the top of the troposphere where cirrus clouds form, but is comparatively unusual near the surface where the air is generally warmer and laden with liquid and/or ice condensation nuclei. One exception is the surface of the high Antarctic Plateau. One year of atmospheric moisture measurement at the surface of Dome C on the East Antarctic Plateau is presented. The measurements are obtained using commercial hygrometry sensors modified to allow air sampling without affecting the moisture content, even in the case of supersaturation. Supersaturation is found to be very frequent. Common unadapted hygrometry sensors generally fail to report supersaturation, and most reports of atmospheric moisture on the Antarctic Plateau are thus likely biased low. The measurements are compared with results from two models implementing cold microphysics parameterizations: the European Center for Medium-range Weather Forecasts through its operational analyses, and the Model Atmosphérique Régional. As in the observations, supersaturation is frequent in the models but the statistical distribution differs both between models and observations and between the two models, leaving much room for model improvement. This is unlikely to strongly affect estimations of surface sublimation because supersaturation is more frequent as temperature is lower, and moisture quantities and thus water fluxes are small anyway. Ignoring supersaturation may be a more serious issue when considering water isotopes, a tracer of phase change and temperature, largely used to reconstruct past climates and environments from ice cores. Because observations are easier in the surface atmosphere, longer and more continuous in situ observation series of atmospheric supersaturation can be obtained than higher in the atmosphere to test parameterizations of cold microphysics, such as those used in the formation of high-altitude cirrus clouds in meteorological and climate models.  
  Programme 1013  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1680-7324 ISBN 1680-7324 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6573  
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Author O. Travnikov, H. Angot, P. Artaxo, M. Bencardino, J. Bieser, F. D'Amore, A. Dastoor, F. De Simone, M. D. C. Diéguez, A. Dommergue, R. Ebinghaus, X. B. Feng, C. N. Gencarelli, I. M. Hedgecock, O. Magand, L. Martin, V. Matthias, N. Mashyanov, N. Pirrone, R. Ramachandran, K. A. Read, A. Ryjkov, N. E. Selin, F. Sena, S. Song, F. Sprovieri, D. Wip, I. Wängberg, X. Yang doi  isbn
openurl 
  Title Multi-model study of mercury dispersion in the atmosphere: atmospheric processes and model evaluation Type Journal
  Year 2017 Publication Atmos. chem. phys. Abbreviated Journal  
  Volume 17 Issue 8 Pages 5271-5295  
  Keywords  
  Abstract Current understanding of mercury (Hg) behavior in the atmosphere contains significant gaps. Some key characteristics of Hg processes, including anthropogenic and geogenic emissions, atmospheric chemistry, and air–surface exchange, are still poorly known. This study provides a complex analysis of processes governing Hg fate in the atmosphere involving both measured data from ground-based sites and simulation results from chemical transport models. A variety of long-term measurements of gaseous elemental Hg (GEM) and reactive Hg (RM) concentration as well as Hg wet deposition flux have been compiled from different global and regional monitoring networks. Four contemporary global-scale transport models for Hg were used, both in their state-of-the-art configurations and for a number of numerical experiments to evaluate particular processes. Results of the model simulations were evaluated against measurements. As follows from the analysis, the interhemispheric GEM gradient is largely formed by the prevailing spatial distribution of anthropogenic emissions in the Northern Hemisphere. The contributions of natural and secondary emissions enhance the south-to-north gradient, but their effect is less significant. Atmospheric chemistry has a limited effect on the spatial distribution and temporal variation of GEM concentration in surface air. In contrast, RM air concentration and wet deposition are largely defined by oxidation chemistry. The Br oxidation mechanism can reproduce successfully the observed seasonal variation of the RM ∕ GEM ratio in the near-surface layer, but it predicts a wet deposition maximum in spring instead of in summer as observed at monitoring sites in North America and Europe. Model runs with OH chemistry correctly simulate both the periods of maximum and minimum values and the amplitude of observed seasonal variation but shift the maximum RM ∕ GEM ratios from spring to summer. O3 chemistry does not predict significant seasonal variation of Hg oxidation. Hence, the performance of the Hg oxidation mechanisms under study differs in the extent to which they can reproduce the various observed parameters. This variation implies possibility of more complex chemistry and multiple Hg oxidation pathways occurring concurrently in various parts of the atmosphere.  
  Programme 1028  
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  Series Volume Series Issue Edition  
  ISSN 1680-7324 ISBN 1680-7324 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6589  
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Author P. Ricaud, E. Bazile, M. del Guasta, C. Lanconelli, P. Grigioni, A. Mahjoub doi  isbn
openurl 
  Title Genesis of diamond dust, ice fog and thick cloud episodes observed and modelled above Dome C, Antarctica Type Journal
  Year 2017 Publication Atmos. Chem. Phys. Abbreviated Journal  
  Volume 17 Issue 8 Pages 5221-5237  
  Keywords  
  Abstract Episodes of thick cloud and diamond dust/ice fog were observed during 15 March to 8 April 2011 and 4 to 5 March 2013 in the atmosphere above Dome C (Concordia station, Antarctica; 75°06′ S, 123°21′ E; 3233 m a.m.s.l.). The objectives of the paper are mainly to investigate the processes that cause these episodes based on observations and to verify whether operational models can evaluate them. The measurements were obtained from the following instruments: (1) a ground-based microwave radiometer (HAMSTRAD, H2O Antarctica Microwave Stratospheric and Tropospheric Radiometers) installed at Dome C that provided vertical profiles of tropospheric temperature and absolute humidity every 7 min; (2) daily radiosoundings launched at 12:00 UTC at Dome C; (3) a tropospheric aerosol lidar that provides aerosol depolarization ratio along the vertical at Dome C; (4) down- and upward short- and long-wave radiations as provided by the Baseline Surface Radiation Network (BSRN) facilities; (5) an ICE-CAMERA to detect at an hourly rate the size of the ice crystal grains deposited at the surface of the camera; and (6) space-borne aerosol depolarization ratio from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) platform along orbits close to the Dome C station. The time evolution of the atmosphere has also been evaluated by considering the outputs from the mesoscale AROME and the global-scale ARPEGE meteorological models. Thick clouds are detected during the warm and wet periods (24–26 March 2011 and 4 March 2013) with high depolarization ratios (greater than 30 %) from the surface to 5–7 km above the ground associated with precipitation of ice particles and the presence of a supercooled liquid water (depolarization less than 10 %) clouds. Diamond dust and/or ice fog are detected during the cold and dry periods (5 April 2011 and 5 March 2013) with high depolarization ratios (greater than 30 %) in the planetary boundary layer to a maximum altitude of 100–300 m above the ground with little trace of precipitation. Considering 5-day back trajectories, we show that the thick cloud episodes are attributed to air masses with an oceanic origin whilst the diamond dust/ice fog episodes are attributed to air masses with continental origins. Although operational models can reproduce thick cloud episodes in the free troposphere, they cannot evaluate the diamond dust/ice fog episodes in the planetary boundary layer because they require to use more sophisticated cloud and aerosol microphysics schemes.  
  Programme 910  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1680-7324 ISBN 1680-7324 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6777  
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Author S. Ishino, S. Hattori, J. Savarino, B. Jourdain, S. Preunkert, M. Legrand, N. Caillon, A. Barbero, K. Kuribayashi, N. Yoshida doi  isbn
openurl 
  Title Seasonal variations of triple oxygen isotopic compositions of atmospheric sulfate, nitrate, and ozone at Dumont d'Urville, coastal Antarctica Type Journal
  Year 2017 Publication Atmos. Chem. Phys. Abbreviated Journal  
  Volume 17 Issue 5 Pages 3713-3727  
  Keywords  
  Abstract Triple oxygen isotopic compositions (Δ17O  = δ17O − 0.52  ×  δ18O) of atmospheric sulfate (SO42−) and nitrate (NO3−) in the atmosphere reflect the relative contribution of oxidation pathways involved in their formation processes, which potentially provides information to reveal missing reactions in atmospheric chemistry models. However, there remain many theoretical assumptions for the controlling factors of Δ17O(SO42−) and Δ17O(NO3−) values in those model estimations. To test one of those assumption that Δ17O values of ozone (O3) have a flat value and do not influence the seasonality of Δ17O(SO42−) and Δ17O(NO3−) values, we performed the first simultaneous measurement of Δ17O values of atmospheric sulfate, nitrate, and ozone collected at Dumont d'Urville (DDU) Station (66°40′ S, 140°01′ E) throughout 2011. Δ17O values of sulfate and nitrate exhibited seasonal variation characterized by minima in the austral summer and maxima in winter, within the ranges of 0.9–3.4 and 23.0–41.9 ‰, respectively. In contrast, Δ17O values of ozone showed no significant seasonal variation, with values of 26 ± 1 ‰ throughout the year. These contrasting seasonal trends suggest that seasonality in Δ17O(SO42−) and Δ17O(NO3−) values is not the result of changes in Δ17O(O3), but of the changes in oxidation chemistry. The trends with summer minima and winter maxima for Δ17O(SO42−) and Δ17O(NO3−) values are caused by sunlight-driven changes in the relative contribution of O3 oxidation to the oxidation by HOx, ROx, and H2O2. In addition to that general trend, by comparing Δ17O(SO42−) and Δ17O(NO3−) values to ozone mixing ratios, we found that Δ17O(SO42−) values observed in spring (September to November) were lower than in fall (March to May), while there was no significant spring and fall difference in Δ17O(NO3−) values. The relatively lower sensitivity of Δ17O(SO42−) values to the ozone mixing ratio in spring compared to fall is possibly explained by (i) the increased contribution of SO2 oxidations by OH and H2O2 caused by NOx emission from snowpack and/or (ii) SO2 oxidation by hypohalous acids (HOX  =  HOCl + HOBr) in the aqueous phase.  
  Programme 414  
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  Series Volume Series Issue Edition  
  ISSN 1680-7324 ISBN 1680-7324 Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 6670  
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