Estimating Gravity Waves at source levels Using Long-Range Infrasound Signals

The atmospheric propagation of infrasound is particularly sensitive to small-scale disturbances that are often unresolved by forecasting models but can significantly alter the waveforms. Among these disturbances, gravity waves (GWs) are notable and are typically parameterized in General Circulation Models (GCMs). This study explores the performance of long-range infrasound modeling in reconstructing non-orographic gravity wave fields. Specifically, we analyze signals recorded at an infrasound station located 300 km from controlled blasts at Hukkakero, Finland, during the late summers of 2014–2017. The ERA5 dataset from the European Centre for Medium-Range Weather Forecasts (ECMWF) is combined with a GW multiwave scheme to derive GW fields in the lower stratosphere. Coarse-grained variables in a column-based atmospheric configuration are used to reconstruct day-to-day GW variability. Our first key finding is the relative success in reconstructing the impact of GWs on infrasound waveforms using acoustic full-wave modeling. The second finding is that infrasound waveforms can be used to calibrate GW characteristics at their source levels in the troposphere. These results demonstrate that infrasound enables the estimation of GW characteristics not well captured by other techniques, suggesting that infrasound can provide a complementary method to calibrate GW parameterizations.