Impact of preindustrial biomass‐burning emissions on the oxidation pathways of tropospheric sulfur and nitrogen

B. Alexander (1) , J. Savarino (2) , K. Kreutz , M. Thiemens

1 Department of Chemistry, UCSD
2 LGGE - Laboratoire de glaciologie et géophysique de l'environnement

Ice core measurements (H 2 O 2 and CH 4 /HCHO) and modeling studies indicate a change in the oxidation capacity of the atmosphere since the onset of the Industrial Revolution due to increases in fossil fuel burning emissions [e.g., Lelieveld et al. , 2002 ; Hauglustaine and Brasseur , 2001 ; Wang and Jacob , 1998 ; Staffelbach et al. , 1991 ]. The mass‐independent fractionation (MIF) in the oxygen isotopes of sulfate and nitrate from a Greenland ice core reveal that biomass‐burning events in North America just prior to the Industrial Revolution significantly impacted the oxidation pathways of sulfur and nitrogen species deposited in Greenland ice. This finding highlights the importance of biomass‐burning emissions for atmospheric chemistry in preindustrial North America and warrants the inclusion of this impact in modeling studies estimating changes in atmospheric oxidant chemistry since the Industrial Revolution, particularly when using paleo‐oxidant data as a reference for model evaluation.

Domaines: Sciences de l'environnement

B. Alexander, J. Savarino, K. Kreutz, M. Thiemens. Impact of preindustrial biomass‐burning emissions on the oxidation pathways of tropospheric sulfur and nitrogen. Journal of Geophysical Research: Atmospheres, 2004, 109 (D8), ⟨10.1029/2003JD004218⟩. ⟨hal-04418348⟩