“…This inclusive, material-based definition avoids the unnecessary confusion of requiring several separate names for the tarball-like particles measured in unprocessed wildfire plumes (Pósfai et al, 2003(Pósfai et al, , 2004Semeniuk et al, 2006;Adachi and Buseck, 2011;China et al, 2013); laboratory biomass smoke (Vernooij et al, 2009;Chakrabarty et al, 2010;Adler et al, 2019); dry-distilled, heat-treated laboratory biomass (Tóth et al, 2014;Hoffer et al, 2016a;Li et al, 2019); fresh marine-engine exhaust Jiang et al, 2019); or atmospheric air masses of unmeasured or unreported photochemical age (Niemi et al, 2006;Hand et al, 2005;Tivanski et al, 2007;Alexander et al, 2008;Zhu et al, 2013). As all of these particles possess similar material properties, a single name, tar brC in general and tarballs for individual spheres, is most appropriate for them.…”