Abstract
AbstractThis study investigates contributions of planetary waves (PWs) to the mean flow in the middle atmosphere during the Northern Hemisphere winter when PW activities are strong, by analyzing satellite data from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). It is suggested that there would be opposite contributions between easterly acceleration by monthly mean stationary planetary waves (STPWs) and westerly acceleration by remaining traveling planetary waves (TRPWs) in the high‐latitude lower mesosphere. When easterly winds appear in the mesosphere, STPWs propagating from the troposphere dissipate in the lower mesosphere to accelerate easterly winds because STPWs could not propagate in easterly wind regions. On the other hand, TRPWs develop there due to the zonal flow instability to accelerate westerly winds. The easterly wind in the mesosphere is frequently triggered by dissipation of westward TRPWs developed in the stratosphere, and would be maintained by these opposite contributions for more than 10 days. Further analyses suggest that the TRPW developing in the high‐latitude lower mesosphere would be an eastward TRPW of zonal wavenumber 1 and a period of 10–40 days. This TRPW would develop and propagate downward to dismiss the baroclinic instability by eliminating warm temperature anomalies formed below the easterly wind region due to the PW dissipation in the mesosphere.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.