Affiliations 

  • 1 Centre for Atmospheric Chemistry University of Wollongong Wollongong New South Wales Australia
  • 2 Department of Geography King's College London London UK
  • 3 School of Natural Sciences and Psychology Liverpool John Moores University Liverpool UK
  • 4 School of Science Monash University, Malaysia Campus Malaysia
  • 5 Department of Mechanical Engineering Imperial College London London UK
  • 6 Department of Earth Sciences, Faculty of Science Vrije Universiteit Amsterdam The Netherlands
J Geophys Res Atmos, 2018 May 27;123(10):5607-5617.
PMID: 30167349 DOI: 10.1029/2017JD027827

Abstract

Southeast Asia experiences frequent fires in fuel-rich tropical peatlands, leading to extreme episodes of regional haze with high concentrations of fine particulate matter (PM2.5) impacting human health. In a study published recently, the first field measurements of PM2.5 emission factors for tropical peat fires showed larger emissions than from other fuel types. Here we report even higher PM2.5 emission factors, measured at newly ignited peat fires in Malaysia, suggesting that current estimates of fine particulate emissions from peat fires may be underestimated by a factor of 3 or more. In addition, we use both field and laboratory measurements of burning peat to provide the first mechanistic explanation for the high variability in PM2.5 emission factors, demonstrating that buildup of a surface ash layer causes the emissions of PM2.5 to decrease as the peat fire progresses. This finding implies that peat fires are more hazardous (in terms of aerosol emissions) when first ignited than when still burning many days later. Varying emission factors for PM2.5 also have implications for our ability to correctly model the climate and air quality impacts downwind of the peat fires. For modelers able to implement a time-varying emission factor, we recommend an emission factor for PM2.5 from newly ignited tropical peat fires of 58 g of PM2.5 per kilogram of dry fuel consumed (g/kg), reducing exponentially at a rate of 9%/day. If the age of the fire is unknown or only a single value may be used, we recommend an average value of 24 g/kg.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.