This project involves the deployment of an airborne dual-channel instrument for the detection of atmospheric NO2 and thermally available NOy species, including N2O5, HNO4, and peroxynitrates. The instrument is based on the laser-induced-fluorescence detection of NO2. The measurements will be made aboard the NCAR C-130 as part of the Tropospheric Ozone Production about the Spring Equinox (TOPSE) program. The TOPSE program is a multi-investigator, aircraft-based program designed to study the high latitude tropospheric spring ozone maximum over North America and the Arctic. This study will provide insight into the partitioning of reactive nitrogen between various forms and their roles in the production and destruction of tropospheric ozone during the onset of spring photochemical activity. The deployment of this instrument will provide the first in situ measurements of N2O5, which is an important reservoir species for reactive nitrogen in the troposphere.
