1B.1
**Water vapor anomoly tropical wave tracing
Paul E. Roundy, Penn State Univ., University Park, PA
This work demonstrates the usefulness of water vapor as a tracer of atmospheric waves, then describes tropical wave statistics derived from the precipitable water (PW) field. Equatorial and other tropical tropospheric waves have been detected using winds, rainfall, and convection. Water vapor may also assist in wave detection, and may be more sensitive to a wave signal than Outgoing Long-wave Radiation (OLR) or winds, since convection may be damped out altogether in some regions and accurate wind analyses may be hard to find over the open oceans. Evidence of waves is found in the modes of change in the (PW) fields. Those modes are influenced by water vapor's interaction with its sources and sinks, advection, and convergence or divergence in the low levels. Because each of these processes are sensitive to wave passage, precipitable water may act as a wave tracer. The NVAP (NASA Water Vapor Project) data set provided global PW data for this project. Analysis revealed zonal wave statistics including velocity and wavelength, possible source regions, and seasonal patterns. Confirmation of results was obtained by appealing to local island rawinsande wind data and global analysis fields.
Session 1B, Tropical Waves And Instabilities I (Parallel with Sessions 1A and 1C) [This session will be dedicated to the memory of Dr. Yoshikazu Hayashi, GFDL]
Tuesday, 23 May 2000, 10:15 AM-12:00 PM
Next paper