Identifier

etd-04042017-162028

Degree

Master of Science (MS)

Department

Geography and Anthropology

Document Type

Access to Thesis Restricted to LSU Campus

Abstract

Every year, tropical cyclones (TCs) bring vast amounts of damage to coastal areas. Japan is an island country frequently struck by TCs. This study uses a modified strike model to understand the spatiotemporal distribution of TC strikes in Japan, and to identify places frequently hit by TCs. A principal component analysis and K–means clustering analysis are used to depict the most fundamental TC strike spatial variations in Japan. Time-lagged Spearman correlations are calculated to identify locations most sensitive to varying Oceanic Ni˜no Index (ONI) phase. Results show the number of TCs striking Japan counts for 1/3 of all TCs in the northwestern Pacific (WP). TC strike frequencies in Japan decrease from south to north. All locations in Japan received at least 6 tropical storm strikes (wind ≥18 m/s) (TS). No typhoon strikes (wind ≥ 33 m/s) (TY) occurred in northeast Hokkaido. Major typhoon (wind ≥ 50 m/s) (MTY) strikes in the four main islands are rare. The earliest TS strikes happened in April, while no MTY strikes occur until June. TC strike frequencies in Japan are quite low before June and from November on. Japan is frequently struck by TCs between June and October, with peaks in August and September. Kyushu, Shikoku and west Honshu have relatively higher strike frequencies in July and August, while TC strike frequencies in southeast Honshu are usually higher in September and October. Locations in Kyushu are found to be sensitive to ONI phase, where the ONI is positively correlated to their annual TC strikes 2 years later.

Date

2017

Document Availability at the Time of Submission

Student has submitted appropriate documentation to restrict access to LSU for 365 days after which the document will be released for worldwide access.

Committee Chair

TREPANIER, Jill

DOI

10.31390/gradschool_theses.4398

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