He joined the laboratory in 2005, and has since measured carbon dioxide (CO2), methane (CH4), ethane (C2H6), nitrous oxide (N2O), and carbon monoxide (CO) from various platforms, including the NOAA WP-3D, CIRPAS/USNRL Twin Otter, and NASA DC-8 aircraft, the CSL mobile laboratory, and at the Boulder Atmospheric Observatory (BAO). He has also measured reactive nitrogen species and ozone (O3) on the NOAA WP-3D and NASA DC-8 platforms.