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Erbland, J., J. Savarino, S. Morin, and M. M. Frey. (2011). Empirical sensitivity of 15N in nitrate to current snow accumulation rates in Antarctica : implications for the interpretation of the deep Vostok ice core (Vol. EGU General Assembly).
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Frey, M. M., N. Brough, J. France, M. D. King, J. Savarino, P. Anderson, A. Jones, and E. Wolff
. (2011). Atmospheric nitrogen oxides (NO and NO2) at Dome C: first observations & implications for reactive nitrogen cycling above the East Antarctic Ice Sheet (Vol. Air-Ice Chemistry Interactions workshop). Bachelor's thesis, , .
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Vicars, W., S. K. Bhattacharya, J. Erbland, and J. Savarino
. (2011). Measurement of the oxygen isotopic anomaly (17O) of tropospheric ozone using a nitrite-coated filter (Vol. EGU General Assembly).
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Frey, M. M., J. Erbland, S. Morin, and J. Savarino
. (2011). Post-depositional fractionation of nitrate stable isotopes in Antarctic snow: towards an ice core proxy of surface UV (Vol. Air-Ice Chemistry Interactions workshop).
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France J L, King M D, Frey M M, Erbland J, Picard G, Preunkert S, MacArthur A, Savarino J, . (2011). Snow optical properties at Dome C (Concordia), Antarctica; implications for snow emissions and snow chemistry of reactive nitrogen. 1680-7316, 11(18), 9787–9801.
Abstract: Measurements of e-folding depth, nadir reflectiv- ity and stratigraphy of the snowpack around Concordia sta- tion (Dome C, 75.10� S, 123.31� E) were undertaken to deter- mine wavelength dependent coefficients (350 nm to 550 nm) for light scattering and absorption and to calculate potential fluxes (depth-integrated production rates) of nitrogen dioxide (NO2) from the snowpack due to nitrate photolysis within the snowpack. The stratigraphy of the top 80 cm of Dome C snowpack generally consists of three main layers:- a sur- face of soft windpack (not ubiquitous), a hard windpack, and a hoar-like layer beneath the windpack(s). The e-folding depths are ~10 cm for the two windpack layers and ~20 cm for the hoar-like layer for solar radiation at a wavelength of 400 nm; about a factor 2–4 larger than previous model esti- mates for South Pole. The absorption cross-section due to impurities in each snowpack layer are consistent with a com- bination of absorption due to black carbon and HULIS (HU- mic LIke Substances), with amounts of 1–2 ng g-1 of black carbon for the surface snow layers. Depth-integrated photo- chemical production rates of NO2 in the Dome C snowpack were calculated as 5.3 × 1012 molecules m-2 s-1 , 2.3 × 1012 molecules m-2 s-1 and 8 × 1011 molecules m-2 s-1 for clear skies and solar zenith angles of 60�, 70� and 80� respectivelyusing the TUV-snow radiative-transfer model. Depending upon the snowpack stratigraphy, a minimum of 85 % of the NO2 may originate from the top 20 cm of the Dome C snow- pack. It is found that on a multi-annual time-scale photolysis can remove up to 80 % of nitrate from surface snow, con- firming independent isotopic evidence that photolysis is an important driver of nitrate loss occurring in the EAIS (East Antarctic Ice Sheet) snowpack. However, the model cannot completely account for the total observed nitrate loss of 90– 95 % or the shape of the observed nitrate concentration depth profile. A more complete model will need to include also physical processes such as evaporation, re-deposition or dif- fusion between the quasi-liquid layer on snow grains and firn air to account for the discrepancies.
Programme: 1011
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Erbland, J. (2011). Isotopic constrains on the interpretation of the nitrate record in the vostok ice core (Vol. Thesis, University of Grenoble).
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Vicars William C, Bhattacharya S K, Erbland Joseph, Savarino Joël, . (2012). Measurement of the 17O-excess (17O) of tropospheric ozone using a nitrite-coated filter
. Rapid Communications in Mass Spectrometry, 26(10), 1219–1231.
Abstract: RATIONALE
Programme: 1011
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Meusinger, C., T. A. Berhanu, J. Erbland, F. Dominé, J. Savarino and M. Johnson. (2012). Meusinger, C., T. A. Berhanu, J. Erbland, F. Dominé, J. Savarino and M. Johnson (2012), Photochemical Isotope Effects in Snowpack Nitrate, in EGU General Assembly, edited by EGU, pp. Abstract EGU2012-9821, poster, Vienna, Austria..
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Frey, M. M., N. Brough, J. L. Thomas, A. E. Jones and J. Savarino. (2012). Atmospheric nitrogen oxides (NO and NO2) in ambient and firn interstitial air at Dome C: implications for modeling reactive nitrogen cycling on the East Antarctic Plateau (Vol. EGU General Assembly).
Abstract: Abstract EGU2012-7594
Programme: 1011
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Cole-Dai, J., J. Savarino, A. Lanciki and M. H. Thiemens . (2012). Isotopic composition of volcanic sulfate aerosols (Vol. 22th annual V. M. Goldschimdt Conference).
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