A numerical evaluation of global oceanic emissions of α-pinene and isoprene Atmospheric Sciences Research Center, State University of New York, 251 Fuller Road, Albany, New York, 12203, USA
Received: 25 August 2009 – Published in Atmos. Chem. Phys. Discuss.: 01 October 2009 Abstract. A numerical evaluation of global oceanic emissions of α-pinene and
isoprene based on both "bottom-up" and "top-down" methods is presented. We
infer that the global "bottom-up" oceanic emissions of α-pinene and
isoprene are 0.013 TgC yr−1 and 0.32 TgC yr−1, respectively. By
constraining global chemistry model simulations with the shipborne
measurement of Organics over the Ocean Modifying Particles in both
Hemispheres summer cruise, we derived the global "top-down" oceanic
α-pinene source of 29.5 TgC yr−1 and isoprene source of
11.6 TgC yr−1. Both the "bottom-up" and "top-down" values are subject to large
uncertainties. The incomplete understanding of the in-situ phytoplankton
communities and their range of emission potentials significantly impact the
estimated global "bottom-up" oceanic emissions, while the estimated total
amounts of the global "top-down" oceanic sources can be influenced by
emission parameterizations, model and input data spatial resolutions,
boundary layer mixing processes, and the treatments of chemical reactions.
The global oceanic α-pinene source and its impact on organic aerosol
formation is significant based on "top-down" method, but is negligible based
on "bottom-up" approach. Our research highlights the importance of carrying
out further research (especially measurements) to resolve the large offset
in the derived oceanic organic emission based on two different approaches.
Revised: 04 February 2010 – Accepted: 09 February 2010 – Published: 19 February 2010
Citation: Luo, G. and Yu, F.: A numerical evaluation of global oceanic emissions of α-pinene and isoprene, Atmos. Chem. Phys., 10, 2007-2015, doi:10.5194/acp-10-2007-2010, 2010.