Evaluation of the global oceanic isoprene source and its impacts on marine organic carbon aerosol.

Abstract : We have combined the first satellite maps of the global distribution of phytoplankton functional type and new measurements of phytoplankton-specific isoprene productivities, with available remote marine isoprene observations and a global model, to evaluate our understanding of the marine isoprene source and its impacts on organic aerosol abundances. Using satellite products to scale up data on phytoplankton-specific isoprene productivity to the global oceans, we infer a mean "bottom-up" oceanic isoprene emission of 0.31±0.08 (1 )Tg/yr. By minimising the mean bias between the model and isoprene observations in the marine atmosphere remote from the continents, we produce a "topdown" oceanic isoprene source estimate of 1.9 Tg/yr. We suggest our reliance on limited atmospheric isoprene data, difficulties in simulating in-situ isoprene production rates in laboratory phytoplankton cultures, and limited knowledge of isoprene production mechanisms across the broad range of phytoplankton communities in the oceans under different environmental conditions as contributors to this difference between the two estimates. Inclusion of secondary organic aerosol (SOA) production from oceanic isoprene in the model with a 2% yield produces small contributions (0.01- 1.4%) to observed organic carbon (OC) aerosol mass at three remote marine sites in the Northern and Southern Hemispheres. Based on these findings we suggest an insignificant role for isoprene in modulating remote marine aerosol abundances, giving further support to a recently postulated primary OC source in the remote marine atmosphere
Type de document :
Article dans une revue
Atmospheric Chemistry and Physics, European Geosciences Union, 2009, 9, pp.1253-1262. 〈10.5194/acp-9-1253-2009〉
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-00480265
Contributeur : Valerie Plouvin <>
Soumis le : lundi 3 mai 2010 - 17:54:43
Dernière modification le : lundi 15 octobre 2018 - 16:37:41

Lien texte intégral

Identifiants

Collections

Citation

S.R. Arnold, D.V. Spracklen, J. Williams, N. Yassaa, J. Sciare, et al.. Evaluation of the global oceanic isoprene source and its impacts on marine organic carbon aerosol.. Atmospheric Chemistry and Physics, European Geosciences Union, 2009, 9, pp.1253-1262. 〈10.5194/acp-9-1253-2009〉. 〈hal-00480265〉

Partager

Métriques

Consultations de la notice

264