Remote sensing and in situ measurements of methane and ammonia emissions from a megacity dairy complex: Chino, CA * Ira Leifer a, * , Christopher Melton a , David M. Tratt b , Kerry N. Buckland b , Lieven Clarisse c , Pierre Coheur c , Jason Frash a , Manish Gupta d , Patrick D. Johnson b , J. Brian Leen d , Martin Van Damme c , Simon Whitburn c , Leonid Yurganov e a Bubbleology Research International (BRI), Solvang, CA 93463, United States b The Aerospace Corporation, 2310 E. El Segundo Blvd., El Segundo, CA 90245, United States c Universit e Libre de Bruxelles (ULB), Brussels, Belgium d ABB, 3055 Orchard Drive, San Jose, CA 95134, United States e University of Maryland, Baltimore County (UMBC), Baltimore, MD 21250, United States article info Article history: Received 4 June 2016 Received in revised form 23 September 2016 Accepted 27 September 2016 Available online xxx Keywords: Methane Ammonia Husbandry Megacity TIR hyperspectral Cavity enhanced absorption spectroscopy Remote sensing IASI abstract Methane (CH 4 ) and ammonia (NH 3 ) directly and indirectly affect the atmospheric radiative balance with the latter leading to aerosol generation. Both have important spectral features in the Thermal InfraRed (TIR) that can be studied by remote sensing, with NH 3 allowing discrimination of husbandry from other CH 4 sources. Airborne hyperspectral imagery was collected for the Chino Dairy Complex in the Los Angeles Basin as well as in situ CH 4 , carbon dioxide (CO 2 ) and NH 3 data. TIR data showed good spatial agreement with in situ measurements and showed significant emissions heterogeneity between dairies. Airborne remote sensing mapped plume transport for ~20 km downwind, documenting topographic effects on plume advection. Repeated multiple gas in situ measurements showed that emissions were persistent on half-year timescales. Inversion of one dairy plume found annual emissions of 4.1  10 5 kg CH 4 , 2.2  10 5 kg NH 3 , and 2.3  10 7 kg CO 2 , suggesting 2300, 4000, and 2100 head of cattle, respectively, and Chino Dairy Complex emissions of 42 Gg CH 4 and 8.4 Gg NH 3 implying ~200k cows, ~30% more than Peischl et al. (2013) estimated for June 2010. Far-field data showed chemical conversion and/or depo- sition of Chino NH 3 occurs within the confines of the Los Angeles Basin on a four to six h timescale, faster than most published rates, and likely from higher Los Angeles oxidant loads. Satellite observations from 2011 to 2014 confirmed that observed in situ transport patterns were representative and suggests much of the Chino Dairy Complex emissions are driven towards eastern Orange County, with a lesser amount transported to Palm Springs, CA. Given interest in mitigating husbandry health impacts from air pollu- tion emissions, this study highlights how satellite observations can be leveraged to understand exposure and how multiple gas in situ emissions studies can inform on best practices given that emissions reduction of one gas could increase those of others. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction 1.1. Methane The important greenhouse gas methane (CH 4 ) has a global warming potential (or relative cumulative forcing index) of ~100 times than of carbon dioxide (CO 2 ) on a decade time-scale com- parable to its lifetime (Myhre et al., 2013, Fig. 8.). Moreover, its abundance is predicted to increase. Meaningful regulatory ap- proaches require accurate current and future budgets, yet un- certainties in even the former remain large (IPCC, 2013; Kirschke et al., 2013), fueling a critical need for robust CH 4 measurement approaches to accurately estimate emissions on local to global scales. Natural CH 4 sources account for 35e50% of the total annual budget of ~550 ± 87 Tg yr 1 while anthropogenic sources contribute the remainder. Natural wetlands emissions contribute * This paper has been recommended for acceptance by Charles Wong. * Corresponding author. E-mail addresses: aira42@yahoo.com, ira.leifer@bubbleology.com (I. Leifer). Contents lists available at ScienceDirect Environmental Pollution journal homepage: www.elsevier.com/locate/envpol http://dx.doi.org/10.1016/j.envpol.2016.09.083 0269-7491/© 2016 Elsevier Ltd. All rights reserved. Environmental Pollution xxx (2016) 1e15 Please cite this article in press as: Leifer, I., et al., Remote sensing and in situ measurements of methane and ammonia emissions from a megacity dairy complex: Chino, CA, Environmental Pollution (2016), http://dx.doi.org/10.1016/j.envpol.2016.09.083