Study of formaldehyde in coastal Antarctica.
type: Dataset
description: With the aim to investigate the production and destruction mechanisms of formaldehyde (HCHO) on a seasonal scale in the remote troposphere, HCHO was monitored over a 13-months period at Dumont d'Urville station, located near the East Coast of the Antarctic continent. Monthly means of 50 ppt in winter and up to 200 ppt in summer were measured. In spring, summer and autumn, a daily variation was detected with amplitude of ≈40 ppt and a maximum during the afternoon. The analytical instrument (Aerolaser, AL4021) deployed for the measurements, was found to be extremely sensitive to ambient temperature variations. The origin of the temperature dependence was investigated, and the deployed analytical method was adapted to eliminate this artefact. The impact of local contamination sources at the measurement site was explored in detail. Anthropogenic combustions were found to have a limited impact (maximum 150 pptv on hourly means) versus a local emission source from ornithogenic soils, induced by the omni-presence of Adelie penguins on the site in summer (maximum 200 pptv on hourly means). From november to march, these sources can introduce an overestimation by a factor 5 of the daily HCHO amplitude, while the influence on the monthly averaged budget can account up to 100 ppt. The raw dataset was thoroughly filtered using local meteorological criteria to eliminate any potential contamination. HCHO measurements were compared to simulations made with a numerical box model developed on the base of the current understanding of the photochemical sources and sinks of HCHO. During summer, methane oxidation was found to be the major source of HCHO production, likely due to enhanced levels of oxidants such as hydroxyl radical (OH) or nitrogen oxide (NO) occurring at DDU since this coastal site is under strong continental influence. Snow emissions and HCHO formation via methyl-hydroperoxyde oxidation complete the summer budget (respectively 10 to 20% of the CH4 oxidation). In contrar…
identifier: NNT: 2011GRENU045
issued: 2026-05-25T13:46:14.005050
language: fr
modified: 2026-05-25T13:46:14.005058
contact point: Organization
  fn: CCSD
keyword: coastal-antarctica
keyword: formaldehyde
keyword: infoeu-reposemanticsdoctoralthesis
keyword: oxidants
keyword: oxydants
keyword: sdustusciences-of-the-universe-physicsearth-sciences
keyword: theses
keyword: zone-cotiere-antarctique
landing page: https://theses.hal.science/tel-00677015

Study of formaldehyde in coastal Antarctica.
type: Distribution
format: HTML
issued: 2026-05-25T13:46:14.092257
modified: 2026-05-25T13:46:13.958158
access URL: https://theses.hal.science/tel-00677015

test_moissonnage_selune
type: Agent