Observations and Ray Tracing of Gravity Waves: Implications for Global Modeling

摘要: Vertical coupling by atmospheric waves is essential for the wind and temperature structure of middle atmosphere. In particular, momentum carried gravity (GWs) governs global circulation in mesosphere instance reason cold summer mesopause. However, small horizontal scales GWs (tens to thousands km) are challenging both modeling observations from satellite. Further, due involved, there a severe lack understanding about themselves, as well dynamical phenomena involving GWs. Until recently, were sparse little was known distribution GWs, their seasonal variation. Therefore, several projects priority program Climate And Weather Sun-Earth System (CAWSES) Deutsche Forschungsgemeinschaft (DFG) have addressed number most pressing problems. Global distributions GW activity fluxes been derived with satellite instruments, resulting first multi-year data sets parameters, covering time variations up duration almost full 11-year solar cycle. addition, tidal sporadic E layers ionosphere studied Positioning (GPS) radio occultation data. Satellite complemented ground-based (radar low-frequency (LF) drift measurements). All these observations, accompanying activities provided important constraints parameterizations. Further aspects propagation usually neglected modeling: ray tracing studies revealed importance non-vertical steps undertaken develop an improved parameterization based on techniques.