Combining AIRS and MLS observations for three‐dimensional gravity wave measurement. Issue 2 (23rd January 2016)

• Record Type: Journal Article
• Authors: Wright, Corwin J.; Hindley, Neil P.; Mitchell, Nicholas J.
• Is Part Of: Geophysical research letters. Volume 43:Issue 2(2016)
• Page Start: 884
• Page End: 893
• Publication Date: 2016-01-23
• Subjects: gravity waves -- satellite -- remote sensing -- momentum flux -- Andes -- stratosphere; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL067233
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Gravity waves play a critical role in transporting energy and momentum between the troposphere, stratosphere, and mesosphere. Satellite measurements provide a powerful tool to investigate these waves across the globe. However, many present methods cannot yield reliable estimates of wave momentum fluxes or the directions of these fluxes. Here we present a new method which addresses this problem by combining observations from Atmospheric Infrared Sounder (AIRS) and Microwave Limb Sounder (MLS) in three dimensions. The method allows direct estimation of horizontal and vertical wavelengths as well as wave amplitude. This in turn allows estimation of both wave momentum flux and the full 3‐D direction of propagation, crucially including the horizontal direction. The method thus allows separation of the data into, for example, eastward and westward momentum fluxes, allowing estimation of the net atmospheric forcing due to these waves. We illustrate this method with a proof‐of‐concept study over the Andes, arguably the largest source of gravity waves in the world. We further critically assess the advantages and disadvantages of our method. Our study highlights the importance of the difference between net and absolute measures of momentum flux. Key Points: We present a new method of detecting gravity waves in 3‐D from satellite data This method allows the computation of net momentum fluxes, i.e., after directional cancelation Our observational filter lies in the highest‐momentum flux part of the spectrum