Acquisition and Analysis of Gravity Wave Image Data for Investigating Antarctic Mesospheric Dynamics

Utah State University, Logan UT

Investigators

Abstract

This proposal is for data acquisition and in-depth data analysis that will utilize existing and new measurements from two key sites in Antarctica to investigate the climatology of short-period (<1 hour) mesospheric gravity waves at high-latitudes and to study their propagation and most copious sources. The proposed program is a follow on to a pilot research, jointly funded by the NSF Office of Polar Programs and the U.K. British Antarctic Survey, to investigate the potential of imaging gravity waves from Antarctica. An all-sky multi-wavelength CCD imager was developed at Utah State University and deployed at Halley Station, Antarctica (76 S) in December 1999 and automatic measurements were initiated in March 2000. The USU/BAS imager has operated very successfully for the past three Austral winters (April-September) providing the first long-term (~5 month/season) image measurement of small-scale gravity wave morphology and dynamics over the Antarctic continent. In 2002, the camera was relocated to Rothera Station (67 S) on the Antarctic Peninsula in preparation for new coordinated measurements using a suite of specialized instrumentation including an Fe temperature lidar, a Bomem OH Interferometer and an MF radar for simultaneous wind measurements. Measurements at these two sites provide a diverse sample of high-latitude gravity wave activity and sources, enabling the investigation of orographic forcing and long-distance ducted wave propagation. The isolated location of Halley on the vast Brunt Ice Shelf greatly removed from localized convective sources that prevail at mid-latitudes and several thousand kilometers from the Antarctic Mountain Range contrasts markedly with Rothera Station which is located on a potential "knife edge" wave generator caused by strong winter polar vortex winds blowing over the near-vertical peninsula cliffs rising as high as 2 km above sea level. As part of our ongoing collaborative program with BAS the operation and maintenance of the all-sky camera is covered by BAS. In this proposal support is requested to continue this exciting collaborative measurements supporting a graduate student for the data analysis.