土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

 
    

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Key Words : Tuvalu, coral cay, cyclone Bebe, gravel movement

1.
 Fongafalex&Fatato, Funangongo, Funamanux_֏b â(«xÌÖÇMË(ôcá¬8= 1972}10™21‘óTuvalu Funafuti AtollTropical Cyclone 3%'h#)(ó«xÖǦatollW)» Bebe՝óë140@ m3$,;+Á‡B 'ó¥¯p ¥ÞL (ô-1 &)ó«xp ~1)ô%,;+Á Cåñ_RòPacific OceanóBåñ\Ròlagoon ‡B'óFunafuti Atoll_åFongafalex&_Ö (ô â(óFatato, Funangongo, FunamanuxÑ1)ô TuvaluFOóï©­՝K¿Á‡
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%ôÛ jFunamanuxó-1Â% -1 FongafalexFunamanuxӔºSñ2010}ò

I_820 土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

(a) July 1971

(b) August 1984

(c) June 2010

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I_821 土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

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I_822 土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

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I_823 土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

-19 Funamanu=ESY8@

-22 Funamanu=WSYD\@

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I_824 土木学会論文集B3（海洋開発）, Vol. 69, No. 2, I_820-I_825, 2013.

5.


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*,k m/.‚q.-Ð _e  † -3‡+ * Funamanuu ɬ! «
‚q!b´!- Ï!DG”trs{ ( J m3) 7F6§ K+.ic- Ï §Ë™?2E:=AE834= ¯³ IPÍpkÎ Funamanuu h¬§Æ! Æ“%-/  fX„ƒndSnd`¡È ~Ï*# -Ð&Ϙu Nº~ !7F6§ K½AE834= ~ IÄ0) a,&() ϧ!v¶^Å 1/3ªy|(–š T * -Ð *’S0MJICA s ,tV$Ã".ˆÐ (Cyclone Bebe‰ lÆ À}0·&Ð § ˜u Ã#K+.²+.-Ð Fongafaleu¹®ÏFongafaleu ¹ ± Fatato, Funan- 
gongou  -˜uɬ j\Æ0¿%-Ïɬj 1) Maragos, J. E., Baines, G. B. K. And Beveridge, P. J. : \Æ!FunamanuuŠ)l Ð !Ï Tropical cyclone Bebe creates a new land formation on Funafuti Atoll, Science, Vol. 181, pp.1161-1164, 1973. Cyclone Bebe‰ K+.§ lÄY! z› m0¨-ÐgW@BCF5 *."Ï Fongafaleu K+.7F6§ k ! zZ . - ÏFatatouR¹ 3u!§

FIELD OBSERVATION OF DEPOSITION OF GRAVEL TO FUNAMANU ISLAND IN TUVALU DUE TO TROPICAL CYCLONE BEBE

Takaaki UDA, Susumu Onaka and Toshiro SAN-NAMI

Funamanu Island is a coral cay with 0.8 km length located in Funafuti Atoll in Tuvalu, and is located 0.6 km west of Fongafale Island with the capitol of Tuvalu. On this island, a large amount of gravel was transported from the offshore zone during Tropical Cyclone Bebe that hit the island in October, 1972. The changes in configuration of the island and the deposition of gravel were investigated using aerial photo- graphs in July 1971 before the cyclone and in August 1984 after the cyclone as well as the satellite image in June 2010. Field observation was also carried out to investigate beach condition of this island and measure the topography of the coral cay.

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