Measurements of NOY condensation on cirrus particles during the SOLVE-I field campaign are analyzed and segregated based on altitude. Significant amounts of NOY were found on the upper tropospheric ice particles; therefore condensation on ice appears to be an important method of NOY removal from the gas phase at the low temperatures of the Scandinavian upper troposphere. For the data set collected on 23 January 2000, NOY condensation on cirrus particles has different properties depending on whether the ice particles are sampled in the upper troposphere, where HNO3 does not dominate NOY, or in the lower stratosphere, where HNO3 does dominate NOY. Nitric acid becomes enriched in the gas phase as NOY condenses on upper tropospheric ice crystals, indicating that a non-HNO3 component of NOY is condensing on upper tropospheric ice particles much faster and at higher concentrations than HNO3 alone on this day. It is unclear which non-HNO3 constituent of NOY is condensing on upper tropospheric ice particles, although N2O5 is the most likely species. This condensation of a non-HNO3 component of NOY is not universal in the upper troposphere but depends on the conditions of the air parcel in which sampling occurred, notably exposure to sunlight.