Elizabeth Asher¹, Troy D Thornberry¹, David W Fahey², Allison C McComiskey³, Drew R Gentner⁴, Ken S Carslaw⁵ and Ru-Shan Gao¹, (1)NOAA Earth System Research Laboratory, Chemical Sciences Division, Boulder, CO, United States, (2)NOAA ESRL, Boulder, CO, United States, (3)Brookhaven National Laboratory, Upton, NY, United States, (4)Yale University, Department of Chemical and Environmental Engineering, New Haven, CT, United States, (5)University of Leeds, Leeds, LS2, United Kingdom