The investigators will fabricate, install, and operate a state-of-the-art all-sky imager at the Mount John Observatory, South Island, New Zealand. The instrument will be used to survey gravity wave activity and several other important dynamical aspects of the upper atmosphere in the southern hemisphere, a region of the globe under-represented in terms of upper atmospheric observations. The imager will record five separate atmospheric nightglow emissions. Four of the emissions originate from the mesosphere and lower thermosphere (MLT) region at 80-100 km, and the fifth is located in the thermosphere near 250 km. The imaging measurements will be combined with simultaneous multi-diagnostic measurements to elucidate the seasonal patterns of occurrence and the propagation characteristics of MLT gravity waves. Short-period atmospheric gravity waves contribute approximately 70 percent of the total momentum budget in the MLT region. The occurrence and behavior of atmospheric tides and planetary waves will also be investigated, as well as several topics related to thermospheric dynamics. Collocated instruments include a Fabry-Perot interferometer and a meteor radar. The observations will also be compared with northern hemisphere measurements to study inter-hemispheric variations in MLT dynamics. The study involves a collaboration with scientists at the University of Canterbury in New Zealand. An undergraduate student will assist with data processing and analysis. The investigators will expose the research to a wider audience by submitting feature-style articles to local newspapers, and they will develop a website devoted to aspects of mesospheric research.
