This project is to continue research using a lidar system on the role that polar stratospheric clouds (PSC's) and stratospheric aerosols play in the annual springtime depletion of ozone over Antarctica. The proposers will upgrade the lidar that was used in the second National Ozone Expedition (NOZE-2) in August and September of 1987 and with it continue to make measurements during August and September of 1988. The lidar is particularly valuable as a aid in deciding when to launch balloons, provided by another institution, that make more detailed measurements of the PSC's. The work will also lead to independent research on the prevalence and nature of the PSC's. A main result of the studies done to date on the Antarctic ozone hole is that the PSC's must play a key role in the chemistry that leads to the destruction of ozone and it is essential that as much as possible learned about the processes involved in order to be able to predict, and possibly forestall, similar occurrences at lower latitudes. SRI International is a leader in the application of lidar technology to environmental measurements.
