Record Details

The long-term variations of east Asia jet stream in the wintertime

ScholarsArchive at Oregon State University

Field Value
Title The long-term variations of east Asia jet stream in the wintertime
Names Huang, Huei-I (creator)
Esbensen, Steve (advisor)
Date Issued 1988-05-24 (iso8601)
Note Graduation date: 1989
Abstract Using rotated principal component analysis, 200mb wind data from
the First GARP Global Experiment are analyzed in the East Asia winter
monsoon region. It is found that there exist slowly eastward-moving
disturbances with a wind-speed maximum embedded in the jet stream
(jet streak). The implied vertical circulation that is transverse to
the jet streak is thermally direct in the entrance region of jet
streak and thermally indirect in the exit region.
The Lagrangian momentum equation for transient part of the flow
indicates that the magnitude of westerly acceleration of an air
parcel moving through the jet streak is related to the Coriolis
acceleration of the transient ageostrophic flow, the advection of
mean momentum by transient flow and momentum conversion between mean
and transient flow due to transient eddies. Estimates of terms in
this equation in the entrance region of jet streak suggest that the
increase of westerly momentum due to the Coriolis acceleration of the
ageostrophic flow is mostly balanced by the decrease due to the mean
easterly momentum advection by the transient jet-streak flow. Thus,
the confluence theory of Namias and Clapp (1949) appears to be valid
for the slowly moving jet streaks in the East Asia jet stream.
Genre Thesis/Dissertation
Topic Atmospheric circulation -- East Asia
Identifier http://hdl.handle.net/1957/29007

© Western Waters Digital Library - GWLA member projects - Designed by the J. Willard Marriott Library - Hosted by Oregon State University Libraries and Press