A novel identification method for stratospheric gravity waves in nadir viewing satellite observations
Year: 2025
Type: article
Abstract: . Atmospheric gravity waves (GWs) are an important mechanism for vertical transport of energy and momentum through the atmosphere. Their impacts are apparent at all scales including aviation, weather, and climate. Identifying stratospheric GWs from satellite observations is challenging due to instrument noise and effects of weather processes, but they can be observed from nadir sounders such as the AIRS instrument onboard Aqua. Here, a new method (hereafter ‘neighbourhood method”) to detect GW information is presented and applied to AIRS data. We describe the concept of the neighbourhood method and use it to investigate GW amplitudes, zonal pseudomomentum fluxes, and vertical wavelengths over 5 years of AIRS data. We compare these results to those calculated from GWs detected using another widely used method based on a defined amplitude cutoff. The neighbourhood method reveals GW patterns in seasonal means that are not visible when using the amplitude cutoff method. Time series analysis suggests that GWs have a larger impact than was previously analysed from the amplitude cutoff detection method. ∼ 25 % of waves detected using the neighbourhood method have amplitudes lower than is visible using the amplitude cutoff method. Three regions are studied in greater depth: the Rocky Mountains, North Africa, and New Zealand/Tasmania. GWs detected using the neighbourhood method have realistic wave phase propagation angles, which are consistent with surface-levels winds from ERA5 climatological reanalyses. Using the neighbourhood method produces new statistics for regional and global GW studies, which compares favourably to the amplitude cutoff GW detection method.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $1,725
Awards: G1130280748, G1520267824, G1789120705, G2132097374, G269782566, MesoS2D:Mesospheric sub-seasonal to decadal predictability, G3168424185, DRivers and Impacts of Ionospheric Variability with EISCAT-3D (DRIIVE), G4565039074, G4830803781, G5156987761, Searching for Upper Atmospheric Waves at the Edge of Space (SURGE), G747970397, TEAMx-FLOW: Flow Dynamics, Scale Interactions and Mountain Waves for TEAMx-UK
OpenAlex ID: W4416979053