All scientific data collected by the Australian Antarctic program (AAp) are eventually described in the Catalogue of Australian Antarctic and Subantarctic Metadata (CAASM). CAASM can be used to search through AAp data descriptions, and it also provides links to access publicly available datasets, which can either be immediately downloaded or obtained from the Australian Antarctic Data Centre (AADC).
This dataset contains atmospheric gravity-wave parameters obtained from images of the infrared emissions from the Meinel band from the night sky above Davis, Antarctica. The camera that provides the images runs continuously during darkness, over intervals set by a yearly almanac of start and stop times. Images are collected and stored approximately every ten seconds. They record the emission intensity over much of the sky. Continuous daylight through summer limits the observation interval to between February and October.
The camera was first installed in the summer of 2011/12 and started operation 2012.
The gravity wave parameters described here were obtained with the following procedure:
- manual identification of clear sky intervals in the image data,
- star removal, flat fielding, and projection of the images onto a linear-scale geographic grid,
- application of a two dimensional FFT algorithm to extract the parameters of wavelike features from image sequences.
More information on this can be obtained from Garcia et al. (1997) and the project investigators.
The gravity wave parameters obtained are horizontal wavelength, wave propagation direction and wave horizontal phase velocity.
Currently only two years worth of processed data are available - 2012, 2013.
Garcia, Taylor and Kelley, Two dimensional spectral analysis of mesospheric airglow image data, Applied Optics, 36, 7374-7385 (1997)
Analysis of the image data yields parameters describing gravity waves in the hydroxyl emission layer, centred near 87 km. These are then used to compile statistics on the characteristics of gravity waves and their relationships to potential source mechanisms.
The operation of the Davis USU camera has supported a number of Antarctic Science Research projects. These include:
Project 4025 – ‘Gravity wave drag parameterization in climate models’. 2012/13 to 2016/17
Project 4065 – ‘Antarctic Gravity Wave Imaging Network (ANGWIN) for Collaborative Mesospheric Research’. 2012/13 to 2016/17
Project 4445 – ��High-latitude gravity wave processes and their parameterization in climate models’ 2017/18 to 2020/21
Further details of the outcomes of these projects can be found on the Antarctic Division website www.aad.gov.au.
Data quality varies according to the availability of continuous clear image streams and this depends on the length of the night and the amount of cloud present.
Gravity-wave parameters extracted from hydroxyl layer emissions suffer from instrumental filtering effects (due to the width of the emission layer) and so do not represent the entire spectrum of gravity waves that may be present at that height for the times given.
These data are not yet publicly available for download.
This data set conforms to the CCBY Attribution License (http://creativecommons.org/licenses/by/4.0/).
Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=Davis_USU_Camera_GW_parameters when using these data.