Articles | Volume 8, issue 9
Atmos. Meas. Tech., 8, 3959–3969, 2015
Atmos. Meas. Tech., 8, 3959–3969, 2015
Research article
29 Sep 2015
Research article | 29 Sep 2015

Characterizing black carbon in rain and ice cores using coupled tangential flow filtration and transmission electron microscopy

A. Ellis1, R. Edwards1, M. Saunders2, R. K. Chakrabarty3, R. Subramanian4, A. van Riessen1, A. M. Smith5, D. Lambrinidis6, L. J. Nunes1, P. Vallelonga7, I. D. Goodwin8, A. D. Moy9,10, M. A. J. Curran9,10, and T. D. van Ommen9,10 A. Ellis et al.
  • 1Physics and Astronomy, Curtin University, Perth, WA, Australia
  • 2Centre for Microscopy, Characterisation, and Analysis, The University of Western Australia, Perth, WA, Australia
  • 3Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
  • 4Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
  • 5Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
  • 6Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT, Australia
  • 7Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
  • 8Marine Climate Risk Group, Department of Environmental Sciences, Macquarie University, NSW, Australia
  • 9Australian Antarctic Division, Channel Highway, Kingston, TAS, Australia
  • 10Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS, Australia

Abstract. Antarctic ice cores have been used to study the history of black carbon (BC), but little is known with regards to the physical and chemical characteristics of these particles in the remote atmosphere. Characterization remains limited by ultra-trace concentrations in ice core samples and the lack of adequate methods to isolate the particles unaltered from the melt water. To investigate the physical and chemical characteristics of these particles, we have developed a tangential flow filtration (TFF) method combined with transmission electron microscopy (TEM). Tests using ultrapure water and polystyrene latex particle standards resulted in excellent blanks and significant particle recovery. This approach has been applied to melt water from Antarctic ice cores as well as tropical rain from Darwin, Australia with successful results: TEM analysis revealed a variety of BC particle morphologies, insoluble coatings, and the attachment of BC to mineral dust particles. The TFF-based concentration of these particles has proven to give excellent results for TEM studies of BC particles in Antarctic ice cores and can be used for future studies of insoluble aerosols in rainwater and ice core samples.

Short summary
Black carbon is an important environmental pollutant, and the structure and composition of these particles are important to measuring their affect on the climate. Historical records of black carbon emissions are stored in polar ice. This paper details a new method to study black carbon preserved in Antarctic ice cores. By combining filtration to concentrate the particles and electron microscopy to characterize them, this method opens up a new avenue to study the history of our atmosphere.