Evidence of a natural marine source of oxalic acid and a possible link to glyoxal

• Published in: Journal of Geophysical Research
• Main Authors: Rinaldi, Matteo, Decesari, Stefano, Carbone, Claudio, Finessi, Emanuela, Fuzzi, Sandro, Ceburnis, Darius, O'Dowd, Colin, Sciare, Jean, Burrows, John, Vrekoussis, Mihalis, Ervens, Barbara, Tsigaridis, Kostas, Facchini, Maria Cristina
• Other Authors: Istituto di Scienze dell'Atmosfera e del Clima Bologna (ISAC), Consiglio Nazionale delle Ricerche (CNR), National University of Ireland Galway (NUI Galway), Chimie Atmosphérique Expérimentale (CAE), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Universität Bremen, University of Colorado Boulder, National Oceanic and Atmospheric Administration (NOAA), Columbia University New York, NASA Goddard Institute for Space Studies (GISS), NASA Goddard Space Flight Center (GSFC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2011
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Mace; Amsterdam Island
• Online Access: https://hal.archives-ouvertes.fr/hal-03203100; https://hal.archives-ouvertes.fr/hal-03203100/document; https://hal.archives-ouvertes.fr/hal-03203100/file/2011JD015659.pdf; https://doi.org/10.1029/2011JD015659

International audience This paper presents results supporting the existence of a natural source of oxalic acid over the oceans. Oxalate was detected in “clean‐sector” marine aerosol samples at Mace Head (Ireland) (53°20′N, 9°54′W) during 2006, and at Amsterdam Island (37°48′S, 77°34′E) from 2003 to 2007, in concentrations ranging from 2.7 to 39 ng m−3 and from 0.31 to 17 ng m−3, respectively. The oxalate concentration showed a clear seasonal trend at both sites, with maxima in spring‐summer and minima in fall‐winter, being consistent with other marine biogenic aerosol components (e.g., methanesulfonic acid, non‐sea‐salt sulfate, and aliphatic amines). The observed oxalate was distributed along the whole aerosol size spectrum, with both a submicrometer and a supermicrometer mode, unlike the dominant submicrometer mode encountered in many polluted environments. Given its mass size distribution, the results suggest that over remote oceanic regions oxalate is produced through a combination of different formation processes. It is proposed that the cloud‐mediated oxidation of gaseous glyoxal, recently detected over remote oceanic regions, may be an important source of submicrometer oxalate in the marine boundary layer. Supporting this hypothesis, satellite‐retrieved glyoxal column concentrations over the two sampling sites exhibited the same seasonal concentration trend of oxalate. Furthermore, chemical box model simulations showed that the observed submicrometer oxalate concentrations were consistent with the in‐cloud oxidation of typical marine air glyoxal mixing ratios, as retrieved by satellite measurements, at both sites.