Atmospheric Rossby wave second harmonic generation observed in the 2018–2019 sudden stratosphere warming event
- 1National Space Science Center, Chinese Academy of Sciences, Key Laboratory of Solar Activity and Space Weather, Kühlungsborn, China
- 2Ann & H.J. Smead Department of Aerospace Engineering Sciences, University of Colorado, Boulder, Boulder, CO, USA
Second harmonic generation (SHG) is widely used in nonlinear optics and radio science in various systems. SHG broadens spectral variability and cascades energy across distinct spatial-temporal scales. Numerical simulations of SHGs of Rossby wave normal modes date back decades. In this study, we report an SHG event of a Rossby wave observed in the atmosphere. Analyzing meteor-radar wind observations over the European and Asian sectors during the sudden stratosphere warming in winter 2018–2019, we identify two transient waves with periods of 16 and 8 days. Temporal evolution, frequency and wavenumber relations, as well as phase couplings revealed by bicoherence and bispectral analyses, confirm that the 16-day signature is an atmospheric manifestation of a Rossby wave normal mode, and its SHG generates the 8-day signature. Our findings validate the theoretically expected Rossby wave nonlinearity.
The current work was publised and featured by Nature Communications at https://doi.org/10.1038/s41467-022-35142-3
How to cite: He, M. and Forbes, J. M.: Atmospheric Rossby wave second harmonic generation observed in the 2018–2019 sudden stratosphere warming event, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10011, https://doi.org/10.5194/egusphere-egu24-10011, 2024.
