Observed and Navy operational global model climatologies of synoptic disturbances over the tropical western Pacific during winter 1991-92
By: C.-P. Chang, Liana Zambresky
Contributors: Zambresky, Liana; Naval Postgraduate School (U.S.). Dept. of Meteorology
Publisher: Naval Postgraduate School; Available from National Technical Information Service
Published: 1993
Place of publication: Monterey, Calif; Springfield, Va
Language: eng
Number of pages: 107
Subjects: CLIMATOLOGY; SYNOPTIC METEOROLOGY
Other titles: NPS-MR-93-003.
Description: This study compares the structure and characteristics of tropical synoptic timescale wave      disturbances over the western Pacific, particularly around the Caroline Islands where six upper      air stations are present, as contained in radiosonde observations and the initial analysis (tau00)      and 48-h forecast (tau48) of the Navy Operational Global Atmospheric Prediction System      (NOGAPS) during northern winter of 1991-1992. The observed, analyzed and forecast      disturbance climatologies are all determined from power spectral and cross-spectral analyses      focusing on the synoptic frequency band encompassing three adjacent period points: 4.6-,      5.3- and 6.4-day. The meridional wind at 850 hPa is used as the principal parameter for      defining the disturbances. The power spectra of the NOGAPS rau00 analysis agree      reasonably closely with the radiosonde observations, but the tau48 forecast shows larger      differences. Nevertheless, the observed horizontal structure of the disturbances are all well      represented in both the analysis and the forecast at all levels. These include the westward      propagation, a 850 hPa wavelength near 33 deg along 10 deg N and near 38 deg along the      equator, a 200 hPa wavelength near 50-60 deg, and a northeast-southwest meridional tilt. In      general, the analysis and the forecast produce a higher spatial coherency than that shown from      the radiosonde observations.
Notes: Title from cover.

"NPS-MR-93-003."

"October 1993."

AD A273 400.

Includes bibliographical references (p. 50-51).

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