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Gravity waves (GWs) play a crucial role in the dynamics of the earth'satmosphere. These waves couple lower, middle and upper atmospheric layers bytransporting and depositing energy and momentum from their sources to greatheights. The accurate parameterisation of GW momentum flux is of keyimportance to general circulation models but requires accurate measurement ofGW properties, which has proved challenging. For more than a decade, thenadir-viewing Atmospheric Infrared Sounder (AIRS) aboard NASA's Aquasatellite has made global, two-dimensional (2-D) measurements ofstratospheric radiances in which GWs can be detected. However, one problemwith current one-dimensional methods for GW analysis of these data is thatthey can introduce significant unwanted biases. Here, we present a newanalysis method that resolves this problem. Our method uses a 2-D Stockwelltransform (2DST) to measure GW amplitudes, horizontal wavelengths anddirections of propagation using both the along-track and cross-trackdimensions simultaneously. We first test our new method and demonstrate thatit can accurately measure GW properties in a specified wave field. We thenshow that by using a new elliptical spectral window in the 2DST, in place ofthe traditional Gaussian, we can dramatically improve the recovery of waveamplitude over the standard approach. We then use our improved method tomeasure GW properties and momentum fluxes in AIRS measurements over tworegions known to be intense hotspots of GW activity: (i) the DrakePassage/Antarctic Peninsula and (ii) the isolated mountainous island of SouthGeorgia. The significance of our new 2DST method is that it provides moreaccurate, unbiased and better localised measurements of key GW propertiescompared to most current methods. The added flexibility offered by thescaling parameter and our new spectral window presented here extend theusefulness of our 2DST method to other areas of geophysical data analysis andbeyond

A two-dimensional Stockwell transform for gravity wave analysis of AIRS measurements