Dispersion & Emission of biogenic aerosols in Antarctica and Atlantic Ocean

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The Antarctic ocean-ice-atmosphere system remains one of the last fully explored regions on the planet. Recent understanding has shown that there can be potentially strong feedbacks between these systems as surface ice melts. These feedback processes between ocean, ice surfaces clouds and aerosols can be very nonlinear and coupled with highly spatially heterogeneous processes. These feedback processes are very poorly understood in the Antarctic atmospheric due to an almost complete lack of quantitative observations of the various different aerosol type, their sources, the contributions due to regional oceanic as well as long range transport, of both biogenic and non-biogenic sources. How these currently contribute and influence cloud and precipitation formation in the region, and more importantly how this will change in future is unknown. Knowing the emission and evolution of the regions aerosol populations and how these change over the Austral Summer-Winter season in response to biogenic activity and solar input is a critical start to enabling understanding and modeling the continent's response to climate warming to answer these questions. In this project the student will make use of real-time aerosol mass spectrometry and UVLIF single particle spectrometric techniques for detection and quantification of airborne aerosol including their organic and inorganic chemical composition as well as primary biological aerosols (PBA), to identify their sources, emission rates, and dispersion patterns. A global N-S transect of the Atlantic Ocean using these continuous sampling techniques will be made on the RRS Attenborough in collaboration with British Antarctic Survey. The ship will transect the equatorial region including the biomass burning and dust outflow regions from Africa eventually sampling the Southern Ocean/Weddell Sea region. Sea region. The objective of this work, which will be conducted with scientists at BAS and Manchester, will be to combine a deeper knowledge of ocean-atmosphere emission processes of these biogenic aerosols and place them in a climate change context using the long term seasonal observations. The work will also include chemical box modelling of nss sulphate and other organic compounds to interpret the diverse aerosol populations measured during the transect. Aerosol-cloud interactions are recognized as the largest uncertainty in current climate models particularly for remote regions such as Antarctica. Furthermore there will be potential for ice shelf sampling as well as Weddell Sea island emission sources including bioaerosols using UVLIF techniques will also be considered. The study will also encompass providing quantifying observations for future studies on the impact of Antarctic ecosystem development due to long-range transport and subsequent Antarctic intra-continent dispersion of primary biological particles (bacteria, fungal spores and pollen) as well as mixed mixed dust and biological material. New real-time measurement techniques now allow the concentrations of general classes of these particles to be detected rapidly, with relative ease allowing these processes to be investigated in detail. Depending on funding this work may be combined with proposed long term seasonal monitoring of biogenic aerosols in Antarctica.