Simon A Carn¹, Nickolay Anatoly Krotkov², Can Li³, Bradford L Fisher⁴, Vitali E. Fioletov⁵, Chris A McLinden⁵ and Fred J. Prata⁶, (1)Michigan Technological University, Department of Geological and Mining Engineering & Sciences, Houghton, MI, United States, (2)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (3)Earth System Science Interdisciplinary Center, College PARK, MD, United States, (4)SSAI, Greenbelt, MD, United States, (5)Environment and Climate Change Canada, Air Quality Research Division, Toronto, ON, Canada, (6)AIRES Pty Ltd, Mt Eliza, Victoria, Australia