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Project title

Study of the composition, sources and radiative properties of aerosols at a west coast location.

Primary Funding Agency

Environmental Protection Agency

Co-Funding Organisation(s)

n/a

Lead Organisation

National University of Ireland Galway (NUIG)

Lead Applicant

Gerard Jennings

Project Abstract

Aerosols affect the global radiation budget directly through scattering of solar radiation and indirectly through the role of the aerosol component of cloud condensation nuclei (CCN) in the activation of clouds which leads to increased reflectivity (albedo) of solar radiation back to space and thus to increased cooling. Yet despite the now recognised growing importance of atmospheric aerosols there is insufficient data available of their microphysical chemical and radiative properties in regions for example such as western Europe and the North Atlantic. Marine aerosols provide a significant contribution to the global radiative budget due to the 70% ocean surface coverage and the low albedo of the ocean surface. Ireland is located at the strategic region between the North Atlantic Ocean and the European continent experiencing vastly different atmospheric composition which requires sustained monitoring.This work describes physico-chemical and radiative measurements taken at the Mace Head atmospheric research station during the period from 2003 i 2006. The measurements are indicative of the medium to long-term measurement programme at the site. These include mass concentration (mass per unit volume) of total suspended particulate (TSP) of aerosol inorganic chemical species; aerosol scattering coefficient and gradient measurements of aerosol chemical species. The relatively continuous nature of the measurement programme permitted both monthly and seasonal characteristics of aerosol parameters to be established.Analytical method inter-comparison which was required due to the change of the analytical laboratory from the University of Miami to Met iireann showed good agreement between the analytical methods providing confidence and continuity in aerosol chemical data time series.Chemical analysis of aerosol samples for the years 2003-2006 shows that the mass concentration of sea-salt has a seasonal pattern with minimum levels in the summer period of around 9.0 g m-3 and enhanced values i by about a factor of 2 i in the winter period of order 14-16 g m-3 due to the increase in winter time of super-micrometre coarse mode aerosol particles (diameter > 1.0 m) with wind speed formed mainly by the bubble bursting process within breaking waves. During winter sea salt contributes to over 95% of the marine TSP mass while the contribution of remaining species is almost negligible.

Grant Approved

�141,000.00

Research Hub

Climate Change

Research Theme

Greenhouse Gas Emissions, Sinks, and Management Systems

Start Date

15/12/2003

Initial Projected Completion Date

28/02/2007