10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Laboratory Study on the Impact of Organic Vapours on Water Uptake of Aerosols
DAWEI HU, David Topping, Gordon McFiggans, University of Manchester
Abstract Number: 256 Working Group: Aerosol Physics
Abstract Clouds have a profound influence on weather and climate. According to the Intergovernmental Panel on Climate Change (IPCC), the impacts of aerosols on clouds are one of the largest uncertainties in estimates of the global radiative forcing. The formation of cloud droplets by the condensation of water vapours on particles can be predicted by traditional Köhler theory, but this treatment is limited to involatile compounds with water vapour only and does not account for the influence of other inorganic or organic vapours. Previous modelling studies reported that co-condensation of inorganic or organic vapours on growing droplets could significantly enhance both cloud condensation nucleus (CCN) and cloud droplet number concentration, thereby influencing cloud albedo and climate. However, until now, there has been no direct observational evidence of this process.
Here, we use a modified Hygroscopic Tandem Differential Mobility Analyser (H-TDMA) system to investigate the growth of inorganic salt particles exposed to both water and organic vapours in the laboratory. The result shows that organic vapour plays an important role in water uptake process of aerosols consistent with our previous predictions. To our knowledge, this study reports the first direct measurement to quantify the influence of organic vapour on the water uptake of aerosols.