Unusually low ozone, HCl, and HNO3 column measurements at Eureka, Canada during winter/spring 2011 - Lindenmaier, R.; Strong, K.; Batchelor, R. L.; Chipperfield, M. P.; Daffer, W. H.; Drummond, J. R.; Duck, T. J.; Fast, H.; Feng, W.; Fogal, P. F.; Kolonjari, F.; Manney, G. L.; et al. (Atmos. Chem. Phys., 2012)