Summertime buildup and decay of lightning NOx and aged thunderstorm outflow above North America

O.R. Cooper, Sabine Eckhardt, J.H Crawford, C. C. Brown, R.C. Cohen, T. H. Bertram, P. Wooldridge, A. Perring, W. H. Brune, X. Ren, D Brunner, S. L. Baughcum