“…Observations of the backscattered shortwave infrared solar spectra also enable the retrieval of CO 2 , CH 4 , and/or CO from SCIAMACHY (Buchwitz et al, 2005), GOSAT (Yoshida et al, 2011), OCO-2 (Eldering et al, 2017), and TROPOMI Hu et al, 2018). Moreover, many atmospheric species have strong spectroscopic signatures in the mid-infrared and can be retrieved from the Earth's thermal emission spectra col- 15 lected by satellite sensors such as MOPITT (Drummond et al, 2010), AIRS (Aumann et al, 2003), TES (Bowman et al, 2006), IASI (Clerbaux et al, 2009), and CrIS (Han et al, 2013). One species of particular significance to tropospheric chemistry and air quality is NH 3 (Baek et al, 2004;Paulot and Jacob, 2014), which has been successfully retrieved from TES (Shephard et al, 2011;Sun et al, 2015a), AIRS (Warner et al, 2016), IASI (Clarisse et al, 2010;Whitburn et al, 2016a;Van Damme et al, 2017), and CrIS (Shephard and Cady-Pereira, 2015;Dammers et al, 2017).…”