| Ray Tracing of Gravity Waves in Vortex Dipoles |
| Shuguang Wang and Fuqing Zhang | |
| Texas A&M Univ. | |
| Chris Snyder | |
| NCAR | |
| Dave Muraki | |
| Simon Fraser Univ. |
| Mesoscale Model and Ray Tracing Model for Dipole Simulation |
| Initial Conditions of the Dipoles: horizontal and Vertical Cross sections |
| Simulated Gravity Waves at 1.5km and 72h from a Surface Dipole |
| Simulated Gravity Waves at 1.5km and 72h from a Surface Dipole |
| Ray Tracing of Gravity Waves |
| 72h Ray Tracing from the Surface Dipole |
| 72 h Ray Tracing from the Surface Dipole |
| 72h Ray Tracing from the Surface Dipole |
| 72h Ray tracing from the Surface Dipole |
| Simulated Gravity Waves at 1.5km and 270h from a Surface Dipole |
| 270h Ray Tracing from the Surface Dipole |
| 270h Ray Tracing from the Surface Dipole |
| 270h Ray Tracing from the Surface Dipole |
| 270h Ray Tracing from the Surface Dipole |
| Gravity Waves from a Mid-level Dipole |
| Ray Tracing from the Mid-level Dipole |
| Ray Tracing from the Mid-level Dipole |
| Gravity Waves from a Dipole at Tropopause Level |
| Ray Tracing from the Dipole at Tropopause Level |
| Ray Tracing from the Dipole at Tropopause Level |
| Summary |
| Gravity waves are simulated at the jet exit regions associated with dipoles. In the surface dipole case, gravity waves are generated near the surface and do not propagate above 5km at later time. In the mid-level dipole case, gravity waves are generated near the jet exit region and propagate both upward and downward. Gravity waves generated from a tropopause level dipole propagate upward mostly. | ||
| Four dimensional ray tracing model accommodates the temporal and spatial variations of the background wind from the dipole simulation. Our results show that as the gravity waves propagate upward, wave characteristics changes significantly. | ||
| Horizontal and vertical wave wavelength decreases. | ||
| Intrinsic group velocity decreases but never vanishes. Wave packets are finally almost advected by weak mean wind. | ||
| Intrinsic frequency are close to inertial frequency. | ||
| How gravity waves are generated has not been fully understood. Spontaneous wave emission could be most possibly generation mechanism for gravity waves in vortex pairs. | ||