Lei Hu¹, Stephen A Montzka², Aleya Kaushik³, Kathryn McKain⁴, Colm Sweeney⁵, John B Miller⁶, Arlyn E Andrews³, Kirk W Thoning¹, Benjamin R Miller⁷, Ian T Baker⁸, J Elliott Campbell⁹, Yoichi Paolo Shiga¹⁰, John Henderson¹¹, Thomas Nehrkorn¹², Marikate Ellis Mountain¹¹, Luke D Schiferl⁴ and Roisin Commane¹³, (1)NOAA Boulder, Boulder, CO, United States, (2)NOAA/ESRL Global Monitoring Division, Boulder, CO, United States, (3)NOAA/ESRL, Global Monitoring Division, Boulder, CO, United States, (4)Harvard University, Cambridge, MA, United States, (5)NOAA ESRL, Global Monitoring Division, Boulder, CO, United States, (6)NOAA, ESRL/GMD, Boulder, CO, United States, (7)Cooperative Institute for Research in Environmental Sciences, Boulder, CO, United States, (8)Colorado State University, Atmospheric Sciences, Fort Collins, CO, United States, (9)University of California Merced, Merced, CA, United States, (10)Stanford University, Stanford, CA, United States, (11)Atmospheric and Environmental Research, Lexington, MA, United States, (12)AER Inc, Lexington, MA, United States, (13)Columbia University of New York City, Palisades, CA, United States