This project will build and fly on balloons instruments for measuring the size and other characteristics of particles found in the arctic stratosphere. These condensation nuclei (CN) and polar stratospheric cloud (PSC) particles play an important role in the destruction of ozone by catalytic action of chlorine. The balloon measurements will be made at the same time as nitric acid (HNO3) vapor measurements will be made by another team from Max Planck Institute, Heidelberg, Germany. Nitric acid is one of the main constituents of the PSC particles. This work is important to increasing understanding of the processes which cause the annual springtime decreases of ozone in both polar regions, and also to help understand the differences between the Arctic and Antarctic stratosphere.
