1. Gradient flux measurements at Mace Head Darius Ceburnis, School of Physics, National University of Ireland Galway, Ireland Marine submicron aerosol sources, sinks and chemical fluxes IGAC, Atmospheric Chemistry in the Anthropocene, 17-21 September 2012, Beijing ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

2. Annual average dry SSA mass production flux as computed by several chemical transport and general circulation models range over nearly 2 orders ofmagnitude. de Leeuw et al., 2011 Textor et al., 2006. Large discrepancies exist between different SS parameterisations ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

3. West coast of Ireland is well positioned to study North Atlantic Ocean with dominant air masses passing over biologically active waters in summer while encountering many storms throughout the year. ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

4. Eddy covariance (EC) technique, relaxed eddy accumulation (REA) method, disjunct eddy covariance (DEC) method, all are not really suitable for aerosol chemistry due to required off-line chemical analysis and long sampling time. Production or removal processes create concentration gradient in the surface layer. Gradient flux method may offer an alternative method to estimate production and/or removal of chemical aerosol species. How can we measure chemical fluxes? ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

5. Source (e.g. ocean surface) C* production deposition C* Deposition to flat/rough surface ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

6. 3m 10m 30m PM1.0 sampler (Leckel PMX) Pre-fired quartz filters Samples were deployed for 7 days, but sampled different number of hours, depending on clean sector conditions ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

7. Eddy covariance w, K z PM1 Gradient samples Chemical fluxes Flux-gradient method block diagram ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

8. Gradient transport theory or K-theory Ceburnis et al., 2008 GRL Concentration gradients can be positive as well as negative ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

9. Un-biased turbulence is a key in determining realistic fluxes ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

11. Primary fluxes – Sea Salt and Sea Spray ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

12. Combined evidence suggests that marine OM is largely insoluble at the origin (sea spray production) only to be removed after being aged (oxidised to become water soluble). Organic matter fluxes – WIOM vs WSOM ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

13. Data broadly agree with the idea proposed by Gantt et al. 2011 that OM enrichment is a combined product of biological activity and wind speed albeit of unknown proportions. ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

14. Comparison of the most recent sea salt parameterisations ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT

15. Acknowledgements J. Keane-Brennan, J. Ovadnevaite, G. Martucci, C.D. O’Dowd, National University of Ireland Galway M. Rinaldi, M.C. Facchini, Institute of Atmospheric Sciences and Climate, C.N.R. Bologna Science Foundation Ireland, EPA Ireland, ESA and SOLAS are acknowledged for funding. ESA-SOLAS-EGU EO4OcAtm-2014, 28-31 October 2014, Frascati, IT