Originally trained in Molecular Biosciences, I am since 2009 focusing on research on Environmental and Climate issues. I am currently pursuing two research directions:
Carbon-containing aerosols, e.g., black carbon (BC) affect the climate system and the quality of the air we breathe. However, these effects are currently associated with large uncertainties, e.g., with respect to emission sources and optical properties. In this line of research we are combining isotopic (e.g., D14C and d13C), molecular (e.g., polycyclic aromatic hydrocarbons, PAHs), and physical (e.g., light-absorption and scattering) techniques with the aim to contribute to constraining the emission sources and atmospheric processing of these components, and investigating the coupling between sources/processing and optical properties. Our approach is largely field-based, with ongoing measurements in South and East Asia, the Arctic and Africa, while chemical/isotopic analysis is conducted here at Stockholm University.
Source Apportionment Calulation Methodology
In this line of research we focus on developing/implementing statistical/numerical analysis techniques for various Environmental and Geo-applications. Much recent focus has been directed towards characterizing the uncertainties in mass-balance source apportionment calculations, mainly by using Monte Carlo techniques in collaboration with Dr. Martin Sköld at the Department of Mathematics, Stockholm University.
A short clip on our joint sampling campaign, with Dr. Michael Gatari, at the University of Nairobi, Kenya:
R-code (courtesy of Martin Sköld, e-mail: email@example.com):
Dual isotope Monte Carlo-based source apportionment from Andersson et al., ES&T 49, 2038-2043, doi: 10.1021/es503855e
Dual isotope Monte Carlo-based source apportionment with spline-modeled time-dependence from Keskitalo et al., Clim. Past 13, 1213-1226, doi: 10.5194/cp-13-1213-2017
14C- bomb spike-resolved Monte Carlo-based source apportionment from Vonk et al., Geochim. Geocosm. Acta 244, 502-521, doi: 10.1016/j.gca.2018.09.034
Latest scientific papers
Source quantification of South Asian black carbon aerosols with isotopes and modeling
Photochemical degradation affects the light absorption of water-soluble brown carbon in the South Asian outflow