Modeling and evaluation of the global sea-salt aerosol distribution: sensitivity to size-resolved and sea-surface temperature dependent emission schemes 1Barcelona Supercomputing Center – Centro Nacional de Supercomputación, Barcelona, Spain
04 Dec 2013
2NASA Goddard Institute for Space Studies, New York, USA
3Department of Applied Physics and Applied Math, Columbia University, New York, USA
4National Centers for Environmental Prediction, College Park, Maryland, USA
5Universitat Politècnica de Catalunya, Barcelona, Spain
Received: 21 Mar 2013 – Published in Atmos. Chem. Phys. Discuss.: 02 May 2013 Abstract. One of the major sources of uncertainty in model
estimates of the global sea-salt aerosol distribution is the
We evaluate a new sea-salt aerosol life cycle
module coupled to the online multiscale chemical transport model
We compare 5 yr global simulations
state-of-the-art sea-salt open-ocean emission schemes with
monthly averaged coarse aerosol optical depth (AOD) from selected AERONET
sun photometers, surface concentration measurements from the
University of Miami's Ocean Aerosol Network, and measurements from
two NOAA/PMEL cruises (AEROINDOEX and ACE1). Model results are
highly sensitive to the introduction of sea-surface-temperature (SST)-dependent emissions
and to the accounting of spume particles production.
ranges from 3888 Tg yr−1 to 8114 Tg yr−1,
lifetime varies between
7.3 h and 11.3 h, and the average column mass
load is between 5.0 Tg and 7.2 Tg.
Coarse AOD is reproduced with an overall
correlation of around 0.5 and with normalized biases ranging from
+8.8% to +38.8%.
Surface concentration is simulated with
normalized biases ranging from −9.5% to +28% and
the overall correlation is around 0.5.
Our results indicate that SST-dependent emission schemes
improve the overall model performance in reproducing surface concentrations.
On the other hand, they lead to an overestimation of the coarse AOD at tropical latitudes,
although it may be affected by uncertainties in the comparison due to the use of all-sky model AOD, the treatment
of water uptake, deposition and optical properties in the model and/or an inaccurate size distribution
Revised: 09 Oct 2013 – Accepted: 02 Nov 2013 – Published: 04 Dec 2013
Citation: Spada, M., Jorba, O., Pérez García-Pando, C., Janjic, Z., and Baldasano, J. M.: Modeling and evaluation of the global sea-salt aerosol distribution: sensitivity to size-resolved and sea-surface temperature dependent emission schemes, Atmos. Chem. Phys., 13, 11735-11755, doi:10.5194/acp-13-11735-2013, 2013.