Initial maintenance of tropical cyclone size in the Western North Pacific

Cheng Shang Lee, K. K. W. Cheung*, Wei Ting Fang, Russell L. Elsberry

*Corresponding author for this work

Research output: Contribution to journalArticle

45 Citations (Scopus)
28 Downloads (Pure)

Abstract

A tropical cyclone (TC) size parameter, which is defined here as the radius of 15 m s-1 near-surface wind speed (R15), is calculated for 145 TCs in the western North Pacific during 2000-05 based on QuikSCAT oceanic winds. For the 73 TCs that intensified to typhoon intensity during their lifetimes, the 33% and 67% respective percentiles of R15 at tropical storm intensity and at typhoon intensity are used to categorize small, medium, and large TCs. Whereas many of the small TCs form from an easterly wave synoptic pattern, the monsoon-related formation patterns are favorable for forming medium to large TCs. Most of these 73 TCs stay in the same size category during intensification, which implies specific physical mechanisms for maintaining TC size in the basin. The 18 persistently large TCs from the tropical storm to the typhoon stage mostly have northwestward or north-northwestward tracks, while the 16 persistently small TCs either move westward-northwestward in lower latitudes or develop at higher latitudes with various track types. For the large TCs, strong low-level southwesterly winds exist in the outer core region south of the TC center throughout the intensification period. The small TCs are more influenced by the subtropical high during intensification. The conclusion is that it is the low-level environment that determines the difference between large and small size storms during the early intensification period in the western North Pacific.

Original languageEnglish
Pages (from-to)3207-3223
Number of pages17
JournalMonthly Weather Review
Volume138
Issue number8
DOIs
Publication statusPublished - Aug 2010

Bibliographical note

© Copyright [2010] American Meteorological Society (AMS). Permission to use figures, tables, and brief excerpts from this work in scientific and educational works is hereby granted provided that the source is acknowledged. Any use of material in this work that is determined to be €œfair use€ under Section 107 of the U.S. Copyright Act or that satisfies the conditions specified in Section 108 of the U.S. Copyright Act (17USC §108, as revised by P.L. 94-553) does not require the AMS€™s permission. Republication, systematic reproduction, posting in electronic form, such as on a web site or in a searchable database, or other uses of this material, except as exempted by the above statement, requires written permission or a license from the AMS. Additional details are provided in the AMS Copyright Policy, available on the AMS Web site located at (http://www.ametsoc.org/) or from the AMS at 617-227-2425 or copyright@ametsoc.org.

Fingerprint Dive into the research topics of 'Initial maintenance of tropical cyclone size in the Western North Pacific'. Together they form a unique fingerprint.

  • Cite this

    Lee, C. S., Cheung, K. K. W., Fang, W. T., & Elsberry, R. L. (2010). Initial maintenance of tropical cyclone size in the Western North Pacific. Monthly Weather Review, 138(8), 3207-3223. https://doi.org/10.1175/2010MWR3023.1