One of the goals of experimental fluid flow is to verify large computational models. This requires the remote measurement of the 3-D velocity vector within a flow. This project uses twin frequency-doubled YAG lasers to record two holograms of the fluid flow at two instants in time. The complete velocity field is then reconstructed by performing 3-D correlations of tracer particles within single volume elements (typically 1 mm;s3).

Advanced optical interconnections based on parallel space division multiplexing using a fiber ribbon or wavelength division multiplexing using multiple wavelengths within a single fiber require new techniques to measure and model performance. These techniques are being developed because the aggregate data rates through these parallel spaces exceed 15 Gbits/s. We are currently developing testing methodologies and equipment to test and model the performance of these high-speed data links.

Current models of ozone depletion over the Antarctic predict that some of the major chemical mechanisms occur on the surface of polar stratospheric clouds (PSCs). In addition, the energy-coupling mechanisms from the lower to the upper atmosphere over the Antarctic are not well understood. We are currently deploying an advanced lidar system at the South Pole that is capable of measuring characteristics of the morphology of the PSCs and also to measure upper atmospheric wave activity using Na as a tracer.

This program is concerned with the propagation of sound waves in the atmosphere, diffraction by obstacles, and imaging of acoustical ``scenes'' through the inhomogeneous atmosphere.

The program is concerned with the development of advanced radio tracking and monitoring techniques for endangered species of animals and birds.

This program is concerned with the development of a monitoring system for low-frequency environment noise, which has superior immunity to false indications produced by wind interacting with the microphone.