Indianapolis whole-city CO₂ and CH₄ emission estimates published to date. Aircraft mass balance data are averages from the following flight days: 2008 (3/28, 4/2, 2/14, 2/15, 4/21, 11/28, 12/20); 2009 (1/7); 2011 (3/1, 4/29, 6/1, 6/30, 7/12); 2012 (11/8); 2014 (11/13, 11/14, 11/17, 11/19, 11/20, 11/21, 11/25, 12/1, 12/3). The three summer dates in 2011 are excluded from the CO₂ aircraft mass balance results due to complications with background conditions in the summer. The confidence interval for the aircraft mass balance average is twice the standard error of the individual estimates. Aircraft mass balance flux estimates represent average emissions from a time window starting few hours before the midday to afternoon flight times. Tower inversion and inventory emissions represent best estimates averaged over the entire time periods noted in the table, including day and night. The area encompassed by the airborne mass balance estimates includes most of the city, but varies somewhat from flight to flight. The tower inversion and inventory estimates represent an 87 × 87 km² region centered on the city. DOI: https://doi.org/10.1525/elementa.147.t2