Observations of Gravity Waves with High-Pass Filtering in the New Generation of Geostationary Imagers and Their Relation to Aircraft Turbulence

Abstract

Abstract This paper introduces a method of image filtering for viewing gravity waves in satellite imagery, which is particularly timely to the advent of the next-generation Advanced Himawari Imager (AHI) and the Advanced Baseline Imager (ABI). Applying a “high pass” filter to the upper-troposphere water vapor channel reveals sub-Kelvin-degree variations in brightness temperature that depict an abundance of gravity wave activity at the AHI/ABI sensitivity. Three examples demonstrate that this high-pass product can be exploited in a forecasting setting to identify possible varieties of turbulence-prone gravity waves that either 1) move roughly orthogonally to the apparent background flow or 2) produce interference as separate wave packets pass through the same location.