south china

ＡＤＶＡＮＣＥＳ ＩＮ ＡＴＭＯＳＰＨＥＲＩＣ ＳＣＩＥＮＣＥＳ，ＶＯＬ ２５

，

ＮＯ．５，２００８，８２４—８４０

Ｓｅｎｓｉｔｉｖｉｔｙ Ｓｔｕｄｙ ｏｆ ｔｈｅ Ｓｅａｓｏｎａｌ Ｍｅａｎ Ｃｉｒｃｕｌａｔｉｏｎ

ｉｎ ｔｈｅ Ｎｏｒｔｈｅｒｎ Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ

ＨＯＮＧ Ｂｏ （宏波）ａｎｄ ＷＡＮＧ Ｄｏｎｇｘｉａｏ（王东晓）

Ｌａｂｏｒａｔｏｒｙ １ｏｒ Ｔｒｏｐｉｃａｌ Ｍａｒｉｎｅ Ｅｎｖｉｒｏｎｍｅｎｔａｌ Ｄｙｎａｍｉｃｓ，Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ Ｉｎｓｔｉｔｕｔｅ ｏｆ Ｏｃｅａｎｏｌｏｇｙ，

Ｃｈｉｎｅｓｅ Ａｃａｄｅｍｙ ｏｆ Ｓｃｉｅｎｃｅｓ，Ｇｕａｎｇｚｈｏｕ ５１０３０１

（Ｒｅｃｅｉｖｅｄ １３ Ｓｅｐｔｅｍｂｅｒ ２００７；ｒｅｖｉｓｅｄ ２８ Ｊａｎｕａｒｙ ２００８）

ＡＢＳＴＲＡＣＴ

Ａ ｓｔｕｄｙ ｏｆ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ（ＳＣＳ）ｉｓ ｃａｒｒｉｅｄ ｏｕｔ ｗｉｔｈ ｔｈｅ ａｉｄ ｏｆ ａ

ｔｈｒｅｅ—ｄｉｍｅｎｓｉｏｎａｌ，ｈｉｇｈ—ｒｅｓｏｌｕｔｉｏｎ ｒｅｇｉｏｎａｌ ｏｃｅａｎ ｍｏｄｅ１．Ｏｎｅ ｃｏｎｔｒｏｌ ａｎｄ ｔｗｏ ｓｅｎｓｉｔｉｖｉｔｙ ｅｘｐｅｒｉｍｅｎｔｓ ａｒｅ

ｐｅｒｆｏｒｍｅｄ ｔｏ ｑｕａｌｉｔａｔｉｖｅｌｙ ｉｎｖｅｓｔｉｇａｔｅ ｔｈｅ ｅｆｆｅｃｔｓ ｏｆ ｓｕｒｆａｃｅ ｗｉｎｄ ｆｏｒｃｉｎｇ，Ｋｕｒｏｓｈｉｏ ｉｎｔｒｕｓｉｏｎ，ａｎｄ ｂｏｔｔｏｍ

ｔｏｐｏｇｒａｐｈｉｃ ｉｎｆｌｕｅｎｃｅ ｏｎ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ．Ｔｈｅ ｍｏｄｅｌ ｒｅｓｕｌｔｓ ｓｈｏｗ ｔｈａｔ ａ ｂｒａｎｃｈ ｏｆ ｔｈｅ

Ｋｕｒｏｓｈｉｏ ｉｎ ｔｈｅ ｕｐｐｅｒ ｌａｙｅｒ ｃａｎ ｉｎｔｒｕｄｅ ｉｎｔｏ ｔｈｅ ＳＣＳ ａｎｄ ｈａｖｅ ｄｉｒｅｃｔ ｉｎｆｌｕｅｎｃｅ ｏｎ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｏｖｅｒ ｔｈｅ

ｃｏｎｔｉｎｅｎｔａｌ ｓｈｅｌｆ ｂｒｅａｋ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ．Ｔｈｅｒｅ ａｒｅ ｓｔｒｏｎｇ ｓｏｕｔｈｗａｒｄ ｐｒｅｓｓｕｒｅ ｇｒａｄｉｅｎｔｓ ａｌｏｎｇ ａ ｚｏｎａｌ ｂｅｌｔ

ｌａｒｇｅｌｙ ｓｅａｗａｒｄ ｏｆ ｔｈｅ ｃｏｎｔｉｎｅｎｔａｌ ｓｌｏｐｅ．Ｔｈｅ ｐｒｅｓｓｕｒｅ ｇｒａｄｉｅｎｔｓ ａｒｅ ｏｐｐｏｓｉｔｅ ｉｎ ｔｈｅ ｓｏｕｔｈｅｒｎ ａｎｄ ｎｏｒｔｈｅｒｎ

ｐａｒｔｓ ｏｆ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ，ｉｎｄｉｃａｔｉｎｇ ｉｎｆｌｏｗ ａｎｄ ｏｕｔｆｌｏｗ ｔｈｒｏｕｇｈ ｔｈｅ ｓｔｒａｉｔ，ｒｅｓｐｅｃｔｉｖｅｌｙ．Ｔｈｅ ｓｅｎｓｉｔｉｖｉｔｙ

ｅｘｐｅｒｉｍｅｎｔｓ ｓｕｇｇｅｓｔ ｔｈａｔ ｔｈｅ Ｋｕｒｏｓｈｉｏ ｉｎｔｒｕｓｉｏｎ ｉｓ ｒｅｓｐｏｎｓｉｂｌｅ ｆｏｒ ｇｅｎｅｒａｔｉｎｇ ｔｈｅ ｉｍｐｏｓｅｄ ｐｒｅｓｓｕｒｅ ｈｅａｄ

ａｌｏｎｇ ｔｈｅ ｓｈｅｌｆ ｂｒｅａｋ ａｎｄ ｈａｓ ｎｏ ｏｂｖｉｏｕｓ ｓｅａｓｏｎａｌ ｖａｒｉａｔｉｏｎｓ．Ｔｈｅ ｌａｔｅｒａｌ ｆｏｒｃｉｎｇ ｔｈｒｏｕｇｈ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ

ａｎｄ Ｔａｉｗａｎ Ｓｔｒａｉｔ ｃａｎ ｉｎｄｕｃｅ ｔｈｅ ｓｏｕｔｈｗｅｓｔｗａｒｄ ｓｌｏｐｅ ｃｕｒｒｅｎｔ ａｎｄ ｔｈｅ ｎｏｒｔｈｅａｓｔｗａｒｄ ＳＣＳⅥ ｒｍ Ｃｕｒｒｅｎｔ

ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ．Ｗｉｔｈｏｕｔ ｔｈｅ ｌａｔｅｒａｌ ｆｏｒｃｉｎｇ．ｔｈｅｒｅ ｉｓ ｎｏ ｈｉｇｈ ｐｒｅｓｓｕｒｅ－ｇｒａｄｉｅｎｔ ｚｏｎａｌ ｂｅｌｔ ｓｅａｗａｒｄ ｏｆ

ｔｈｅ ｃｏｎｔｉｎｅｎｔａｌ ｓｌｏｐｅ．Ｔｈｅ ｗｉｎｄ ｆｏｒｃｉｎｇ ｍａｉｎｌｙ ｃａｕｓｅｓ ｔｈｅ ｓｅａｓｏｎａｌ ｖａｒｉａｔｉｏｎ ｏｆ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ ＳＣＳ．

Ｔｈｅ ｗｉｎｄ．ｉｎｄｕｃｅｄ ｗａｔｅｒ ｐｉｌｅ．ｕｐ ｒｅｓｕｌｔｓ ｉｎ ｔｈｅ ｓｏｕｔｈｗａｒｄ ｈｉｇｈ ｐｒｅｓｓｕｒｅ ｇｒａｄｉｅｎｔ ａｌｏｎｇ ｔｈｅ ｎｏｒｔｈｗｅｓｔｅｒｎ

ｂｏｕｎｄａｒｙ ｏｆ ｔｈｅ ｂａｓｉｎ．Ｗｉｔｈｏｕｔ ｔｈｅ ｂｌｏｃｋｉｎｇ ｏｆ ｔｈｅ ｐｌａｔｅａｕ ａｒｏｕｎｄ Ｄｏｎｇｓｈａ Ｉｓｌａｎｄｓ，ｔｈｅ ｉｎｔｒｕｄｅｄ Ｋｕｒｏｓｈｉｏ

ｔｅｎｄｓ ｔｏ ｅｘｔｅｎｄ ｎｏｒｔｈｗｅｓｔ ａｎｄ ｔｈｅ ＳＣＳ ｂｒａｎｃｈ ｏｆ ｔｈｅ Ｋｕｒｏｓｈｉｏ ｂｅｃｏｍｅｓ ｗｉｄｅｒ ａｎｄ ｓｔｒｏｎｇｅｒ．Ｔｈｅ ａｎａｌｙｓｅｓ

ｐｒｅｓｅｎｔｅｄ ｈｅｒｅ ａｒｅ ｑｕａｌｉｔａｔｉｖｅ ｉｎ ｎａｔｕｒｅ ｂｕｔ ｓｈｏｕｌｄ ｌｅａｄ ｔｏ ａ ｂｅｔｔｅｒ ｕｎｄｅｒｓｔａｎｄｉｎｇ ｏｆ ｔｈｅ ｏｃｅａｎｉｃ ｒｅｓｐｏｎｓｅｓ

ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ ｔｏ ｔｈｅｓｅ ｅｘｔｅｒｎａｌ ｉｎｆｌｕｅｎｃｅ ｆａｃｔｏｒｓ．

Ｋｅｙ ｗｏｒｄｓ：ｎｏｒｔｈｅｒｎ Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ，ｃｉｒｃｕｌａｔｉｏｎ，ｗｉｎｄ ｆｏｒｃｉｎｇ，Ｋｕｒｏｓｈｉｏ ｉｎｔｒｕｓｉｏｎ，ｂｏｔｔｏｍ ｔｏｐｏｇｒａｐｈｙ

Ｃｉｔａｔｉｏｎ：Ｈｏｎｇ，Ｂ．，ａｎｄ Ｄ．Ｗａｎｇ，２００８：Ｓｅｎｓｉｔｉｖｉｔｙ ｓｔｕｄｙ ｏｆ ｔｈｅ ｓｅａｓｏｎａｌ ｍｅａｎ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ Ｎｏｒｔｈｅｒｎ

Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ．Ａｄｖ．Ａｔｍｏｓ．Ｓｃｉ，２５（５），８２４－８４０，ｄｏｉ：１０．１００７／ｓ００３７６—００８—０８２４—８．

１． Ｉｎｔｒｏｄｕｃｔｉｏｎ

Ｔｈｅ Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ（ＳＣＳ １ ｉＳ ｔｈｅ ｌａｒｇｅｓｔ ｍａｒｇｉｎａｌ

ｓｅａ ｉｎ ｔｈｅ ｔｒｏｐｉｃｓ ｆＦｉｇ．１ａ）．Ｉｔｓ ｄｅｅｐ ｃｅｎｔｒａｌ ｂａｓｉｎ ｉｓ

ｂｏｒｄｅｒｅｄ ｂｙ ｔｗｏ ｂｒｏａｄ ｓｈｅｌｆ ｒｅｇｉｏｎｓ ｔｏ ｔｈｅ ｎｏｒｔｈ ａｎｄ

ｓｏｕｔｈ．ｅａｃｈ ｗｉｔｈ ａ ｗａｔｅｒ ｄｅｐｔｈ ｏｆ ｌｅｓｓ ｔｈａｎ ２００ ｍ．

Ｔｏ ｔｈｅ ｅａｓｔ ａｎｄ ｗｅｓｔ．ｔｈｅ ｃｏｎｔｉｎｅｎｔａｌ ｓｌｏｐｅｓ ａｒｅ ｖｅｒｙ

ｓｔｅ印，ｗｉｔｈ ｐｒａｃｔｉｃａｌｌｙ ｎｏ ｃｏｎｔｉｎｅｎｔａｌ ｓｈｅｌｆ．Ｔｈｅ ｎｏｒｔｈ．

ｅｒｎ ｓｈｅｌｆ ｅｘｔｅｎｄｓ ｆｒｏｍ Ｔａｉｗａｎ ｓｏｕｔｈｗｅｓｔｗａｒｄ ｔｏ １５。Ｎ，

ａｎｄ ａｖｅｒａｇｅｓ １５０ ｋｍ ｉｎ ｗｉｄｔｈ．Ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ．ｗｉｔｈ

ａ ｓｉｌｌ ｄｅｐｔｈ ｏｆ ｍｏｒｅ ｔｈａｎ ２０００ ｍ，ｃｏｎｎｅｃｔｓ ｔｈｅ ＳＣＳ

ｗｉｔｈ ｔｈｅ Ｐａｃｉｆｉｃ Ｏｃｅａｎ．Ｔｈｅ ｉｎｔｒｕｓｉｏｎ ｏｆ ｔｈｅ Ｋｕｒｏｓｈｉｏ

ｔｈｒｏｕｇｈ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ ｈａｓ ａ ｄｉｒｅｃｔ ｉｎｆｌｕｅｎｃｅ ｏｎ ｔｈｅ

ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ．

Ｃｏｒｒｅｓｐｏｎｄｉｎｇ ａｕｔｈｏｒ：ＨＯＮＧ Ｂｏ，ｈｏｎｇｂｏ＠ｓｃｓｉｏ．ａｃ．ｃｉ１

Ｔｈｅ ｕｐｐｅｒ．１ａｙｅｒ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ ｔｈｅ ＳＣＳ ｉｓ ｐｒｉｍａｒｉｌｙ

ｃｏｎｔｒｏｌｌｅｄ ｂｙ ｔｈｅ Ｅａｓｔ Ａｓｉａｎ ｍｏｎｓｏｏｎ．Ｍａｎｙ ｉｎｔｅｒｎａ－

ｔｉｏｎａｌ ｐｒｏｊｅｃｔｓ ｈａｖｅ ｂｅｅｎ ｐｕｔ ｉｎ ｐｒａｃｔｉｃｅ ｉｎ ｏｒｄｅｒ ｔｏ

ｂｅｔｔｅｒ ｕｎｄｅｒｓｔａｎｄ ｔｈｅ Ｅａｓｔ Ａｓｉａｎ ｍｏｎｓｏｏｎ ａｎｄ ｉｔｓ ｉｎ．

ｔｅｒａｃｔｉｏｎ ｗｉｔｈ ｔｈｅ ＳＣＳ．Ｔｈｅ Ｓｏｕｔｈ Ｃｈｉｎａ Ｓｅａ Ｍｏｎｓｏｏｎ

Ｅｘｐｅｒｉｍｅｎｔ（ＳＣＳＭＥＸ）ｉｓ ｏｎｅ ｏｆ ｔｈｅ ｐｒｏｊｅｃｔｓ，ｗｈｉｃｈ

ｐｒｏｖｉｄｅｄ ｅｘｃｅｌｌｅｎｔ ｄａｔａｓｅｔｓ ｆｏｒ ｓｔｕｄｙｉｎｇ ｔｈｅ ｉｎｔｅｒａｃ．

ｔｉｏｎ ｏｆ ｔｈｅ ｓｕｍｍｅｒ ｍｏｎｓｏｏｎ ａｎｄ ｔｈｅ ＳＣＳ ｃｉｒｃｕｌａｔｉｏｎ

（Ｄｉｎｇ ｅｔ ａ１．，２００４）． Ｇｅｎｅｒａｌｌｙ，ｔｈｅ ｓｏｕｔｈｗｅｓｔ ｍｏｎ．

ｓｏｏｎ ｐｒｅｖａｉｌｓ ｆｒｏｍ Ｊｕｎｅ ｔｏ Ｓｅｐｔｅｍｂｅｒ，ａｎｄ ａ ｍｕｃｈ

ｓｔｒｏｎｇｅｒ ｎｏｒｔｈｅａｓｔ ｍｏｎｓｏｏｎ ｔａｋｅｓ ｏｖｅｒ ｆｒｏｍ Ｎｏｖｅｍ．

ｂｅｒ ｔｏ Ｍａｒｃｈ．Ｔｈｅ ｗｉｎｄ ｓｔｒｅｓｓ ｆｉｅｌｄｓ ｓｈｏｗ ｔｈａｔ ｔｈｅ

ｎｏｒｔｈｅａｓｔｅｒｌｖ ｗｉｎｄｓ ｐｒｅｖａｉｌ ｏｖｅｒ ｔｈｅ ｗｈｏｌｅ ｒｅｇｉｏｎ ｄｕｒ．

ｉｎｇ Ｄｅｃｅｍｂｅｒ－Ｆｅｂｒｕａｒｙ，ｗｈｅｒｅａｓ ｗｅａｋｅｒ ｓｏｕｔｈｅａｓｔｅｒｌｙ

维普资讯

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irculationofthe

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gated

previousl

y(e．g．，

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yrtki

，

196

1

：

Xueta1．，1982

；

Lieta1．，1996

；

Fangeta1．．1998

；

Chueta1．，

1999

；QUeta1．，

2000

；

Caieta1．，

2002

；

Yangeta1．

．2002

；

、veieta1．．2003

；

Xueeta1．

．2004

；

Ganet

a1．，

2006)．Mostofthest

udiesaresumma—

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areviewb

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Hueta1．(20001．Ingeneral

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，

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Huangeta1．f199

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Liuf19981con

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ould

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1991

；Que

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t

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维普资讯

８２６ ＳＥＮＳＩＴＩＶＩＴＹ ＳＴＵＤＹ ｏＮ ＣＩＲＣＵＬＡＴＩＯＮ ＩＮ ＮＯＲＴＨＥＲＮ ＳＯＵＴＨ ＣＨＩＮＡ ＳＥＡ

ｔｈｅ Ｋｕｒｏｓｈｉｏ ｉｎｔｒｕｄｅｄ ｓｔｅａｄｉｌｙ ａｎｄ ｐｅｒｓｉｓｔｅｎｔｌｙ ｉｎｔｏ

ｔｈｅ ＳＣＳ；ｐａｒｔ ｏｆ ｔｈｅ ｉｎｔｒｕｄｅｄ Ｋｕｒｏｓｈｉｏ ｅｘｉｔｅｄ ｔｈｅ ＳＣＳ

ｖｉａ ｔｈｅ ｎｏｒｔｈｅｒｎ Ｌｕｚｏｎ Ｓｔｒａｉｔ ａｎｄ ｒｅｕｎｉｔｅｄ ｗｉｔｈ ｔｈｅ

ｍａｉｎ ｓｔｒｅａｍ ｏｆ ｔｈｅ Ｋｕｒｏｓｈｉｏ．

Ｓｅｖｅｒａｌ ｓｔｕｄｉｅｓ ｈａｖｅ ｎｏｔｅｄ ｔｈａｔ ｔｈｅ Ｄｏｎｇｓｈａ Ｉｓ—

ｌａｎｄｓ ｈａｓ ａ ｂｌｏｃｋｉｎｇ ｅｆｆｅｃｔ ｏｎ ｔｈｅ ｗｅｓｔｗａｒｄ ｉｎｔｒｕｓｉｏｎ

ｏｆ ｔｈｅ Ｋｕｒｏｓｈｉｏ ａｌｏｎｇ ｔｈｅ ｃｏｎｔｉｎｅｎｔａｌ ｓｌｏｐｅ（ｅ．ｇ．，Ｍａ，

１９８７；Ｈｓｕｅｈ ａｎｄ Ｚｈｏｎｇ，２００４）．Ｈｓｕｅｈ ａｎｄ Ｚｈｏｎｇ

（２００４１ ｐｒｏｐｏｓｅｄ ｔｈａｔ ｔｈｅ ｃｏｌｌｉｓｉｏｎ ｏｆ ｔｈｅ Ｋｕｒｏｓｈｉｏ ｉｎ—

ｔｒｕｓｉｏｎ ｗｉｔｈ ｔｈｅ ｃｏｎｔｉｎｅｎｔａｌ ｓｌｏｐｅ ｎｅａｒ Ｄｏｎｇｓｈａ Ｉｓ—

ｌａｎｄｓ ｃｏｕｌｄ ｉｎｄｕｃｅ ｐｒｅｓｓｕｒｅ ｈｅａｄ ａｌｏｎｇ ｔｈｅ ｃｏｎｔｉｎｅｎ—

ｔａｌ ｓｈｅｌｆ ｂｒｅａｋ．Ｔｈｅ ｉｎｔｒｕｄｅｄ Ｋｕｒｏｓｈｉｏ ｓｐｌｉｔ ｉｎｔｏ ｔｗｏ

ｂｒａｎｃｈｅｓ ａｆｔｅｒ ｔｈｅ ｃｏｌｌｉｓｉｏｎ．Ｔｈｅ ｍａｉｎ ｓｔｒｅａｍ ｏｆ ｔｈｅ

ｉｎｔｒｕｄｅｄ Ｋｕｒｏｓｈｉｏ ｖｅｅｒｅｄ ｔｏｗａｒｄ ｔｈｅ ｎｏｒｔｈｅａｓｔ ａｎｄ

ｅｖｅｎｔｕａｌｌｙ ｅｘｉｔｅｄ ｔｈｅ ＳＣＳ ｔｈｒｏｕｇｈ ｔｈｅ Ｔａｉｗａｎ Ｓｔｒａｉｔ

ａｎｄ ｔｈｅ ｎｏｒｔｈｅｒｎ ｐａｒｔ ｏｆ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ．ｗｈｉｌｅ ｔｈｅ

ｒｅｍａｉｎｉｎｇ ｐａｒｔ ｗａｓ ｃａｌｌｅｄ ｔｈｅ ＳＣＳＢＫ．

Ｔｈｅ ｃｏｍｂｉｎａｔｉｏｎ ｏｆ ｓｕｒｆａｃｅ ｗｉｎｄ ｆｏｒｃｉｎｇ．Ｋｕｒｏｓｈｉｏ

ｉｎｔｒｕｓｉｏｎ．ａｎｄ ｂｏｔｔｏｍ ｔｏｐｏｇｒａｐｈｉｃ ｉｎｆｌｕｅｎｃｅ ｃｏｎ—

ｔｒｉｂｕｔｅｓ ｔｏ ｔｈｅ ｃｏｍｐｌｅｘ ｄｙｎａｍｉｃｓ ｏｆ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ

ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ．Ｎｕｍｅｒｉｃａｌ ｍｏｄｅｌｓ ｃａｎ ｂｅ ｉｍｐｏｒｔａｎｔ

ｔｏｏｌｓ ｉｎ ｈｅｌｐｉｎｇ ｔｏ ｓｅｐａｒａｔｅ ｔｈｅｓｅ ｄｙｎａｍｉｃｓ ａｎｄ ｃｌａｒｉ

．

ｆｙ

ｔｈｅ ｃｏｎｔｒｉｂｕｔｉｏｎｓ ｏｆ ｅａｃｈ ｉｎｆｌｕｅｎｃｉｎｇ ｆａｃｔｏｒ．Ｔｈｅ ｐｕｒ—

ｐｏｓｅ ｏｆ ｔｈｉｓ ｐａｐｅｒ ｉｓ ｔｏ ｑｕａｌｉｔａｔｉｖｅｌｙ ｉｎｖｅｓｔｉｇａｔｅ ｔｈｅ

ｅｆｆｅｃｔ ｏｆ ｄｉｆｆｅｒｅｎｔ ｆｏｒｃｉｎｇ ｆａｃｔｏｒｓ ｏｎ ｔｈｅ ｃｉｒｃｕｌａｔｉｏｎ ｉｎ

ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ ｔｈｒｏｕｇｈ ａ ｓｅｒｉｅｓ ｏｆ ｎｕｍｅｒｉｃａｌ ｅｘｐｅｒ－

ｉｍｅｎｔｓ．Ｗｌｅ ｆｏｃｕｓ ｏｎ ｔｈｅ ｏｃｅａｎｉｃ ｒｅｓｐｏｎｓｅｓ ｔｏ ｔｈｅ ｉｎ．

ｆｌｕｅｎｃｅ ｏｆ ｌｏｃａｌ ｗｉｎｄ ｆｏｒｃｉｎｇ，ｌａｔｅｒａｌ ｍｏｍｅｎｔｕｍ ｆｌｕｘ，

ａｎｄ ｂｏｔｔｏｍ ｔｏｐｏｇｒａｐｈｙ，ａｎｄ ａｎａｌｙｚｅ ｔｈｅ ａｓｓｏｃｉａｔｅｄ

ｓｅａｓｏｎａｌ ｆｅａｔｕｒｅｓ ｏｆ ｔｈｅｓｅ ｐｒｏｃｅｓｓｅｓ．

Ｔｈｅ ｍｏｄｅｌ ｃｏｎｆｉｇｕｒａｔｉｏｎ ａｎｄ ｎｕｍｅｒｉｃａｌ ｅｘｐｅｒｉｍｅｎｔ

ｄｅｓｉｇｎｓ ａｒｅ ｉｎｔｒｏｄｕｃｅｄ ｉｎ ｓｅｃｔｉｏｎ ２．Ｍｏｄｅｌ－ｄａｔａ ｃｏｒｎ—

ｐａｒｉｓｏｎｓ ａｒｅ ｇｉｖｅｎ ｉｎ ｓｅｃｔｉｏｎ ３．Ｂａｓｅｄ ｏｎ ｔｈｅ ａｇｒｅｅ—

ｍｅｎｔ ｂｅｔｗｅｅｎ ｔｈｅ ｓｉｍｕｌａｔｉｏｎｓ ａｎｄ ｔｈｅ ｏｂｓｅｒｖａｔｉｏｎｓ，

ｍｏｄｅｌ ｒｅｓｕｌｔｓ ｏｆ ａ ｓｅｒｉｅｓ ｏｆ ｅｘｐｅｒｉｍｅｎｔｓ ａｒｅ ａｎａｌｙｚｅｄ

ｉｎ ｓｅｃｔｉｏｎ ４ ｔｏ ｉｎｖｅｓｔｉｇａｔｅ ｔｈｅ ｒｅｓｐｏｎｓｅｓ ｏｆ ｔｈｅ ｃｉｒｃｕ—

ｌａｔｉｏｎ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ ｔｏ ｄｉｆｉｅｒｅｎｔ ｆｏｒｃｉｎｇ ｆａｃｔｏｒｓ．

Ｄｉｓｃｕｓｓｉｏｎ ａｎｄ ｃｏｎｃｌｕｓｉｏｎｓ ａｒｅ ｐｒｏｖｉｄｅｄ ｉｎ ｓｅｃｔｉｏｎ ５．

２． Ｎｕｍｅｒｉｃａｌ ｏｃｅａｎ ＩＴＩＯｄｅｌ

Ｔｈｅ ｍｏｄｅｌ ｕｓｅｄ ｉｎ ｔｈｉｓ ｓｔｕｄｙ ｉｓ ｔｈｅ Ｐｒｉｎｃｅｔｏｎ

Ｏｃｅａｎ Ｍｏｄｅｌ（ＰＯＭ）．Ｂｒｉｅｆｌｙ，ｔｈｅ ＰＯＭ ｉｓ ａ ｈｙｄｒｏ－

ｓｔａｔｉｃ，ｆｒｅｅ ｓｕｒｆａｃｅ，ｓｉｇｍａ ｃｏｏｒｄｉｎａｔｅ，ｐｒｉｍｉｔｉｖｅ ｅｑｕａ－

ｔｉｏｎ ｍｏｄｅｌ，ｗｉｔｈ ａｎ ｅｍｂｅｄｄｅｄ ｔｕｒｂｕｌｅｎｃｅ ｓｕｂｍｏｄｅ１．

Ｆｏｒ ａｎ ｉｎ—ｄｅｐｔｈ ｄｅｓｃｒｉｐｔｉｏｎ ｏｆ ｔｈｅ ｍｏｄｅ１ ａｎｄ ｔｈｅ ａｎ—

ｍｅｒｉｃａｌ ｔｅｃｈｎｉｑｕｅｓ，ｔｈｅ ｒｅａｄｅｒ ｉｓ ｒｅｆｅｒｒｅｄ ｔｏ Ｂｌｕｍｂｅｒｇ

ａｎｄ Ｍｅｌｌｏｒ（１９８７）．Ｄｅｔａｉｌｓ ｏｆ ｔｈｅ ｍｏｄｅｌ ｃｏｎｆｉｇｕｒａｔｉｏｎ

ｕｓｅｄ ｉｎ ｔｈｉｓ ｓｔｕｄｙ ａｒｅ ｐｒｅｓｅｎｔｅｄ ｂｅｌｏｗ．

２．１ Ｍｏｄｅｌ ｃｏｎｆｉｇｕｒａｔｉｏｎ

Ｉｎ ｏｒｄｅｒ ｔｏ ｉｎｔｒｏｄｕｃｅ ｒｅａｌｉｓｔｉｃ Ｋｕｒｏｓｈｉｏ ｄｙｎａｍｉｃ

ｐｒｏｃｅｓｓｅｓ ａｔ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ，ｔｈｅ ｍｏｄｅｌ ｄｏｍａｉｎ ｉｓ ｅｘ－

ｔｅｎｄｅｄ ｆｒｏｍ ｔｈｅ ＳＣＳ ｔｏ ｃｏｖｅｒ ｐａｒｔ ｏｆ ｔｈｅ Ｎｏｒｔｈ Ｐａｃｉｆｉｃ

ａｎｄ ｔｈｅ Ｅａｓｔ Ｃｈｉｎａ Ｓｅａ（Ｆｉｇ．１ｂ）．Ｔｈｅ ｈｏｒｉｚｏｎｔａｌ

ＶｏＬ．２５

ｇｒｉｄ ｅｍｐｌｏｙｓ ａ ｃｕｒｖｉｌｉｎｅａｒ ｏｒｔｈｏｇｏｎａｌ ｓｙｓｔｅｍ ｗｉｔｈ ａ

ｖａｒｉａｂｌｅ ｒｅｓｏｌｕｔｉｏｎ．Ｍｅｔｚｇｅｒ ａｎｄ Ｈｕｒｌｂｕｒｔ（２００１）ＳＵｇ－

ｇｅｓｔｅｄ ｔｈａｔ ｔｈｅ ａｃｃｕｒａｔｅ ｒｅｐｒｅｓｅｎｔａｔｉｏｎ ｏｆ ｔｈｅ ｎｏｒｔｈ－

ｓｏｕｔｈ ｉｓｌａｎｄ ｃｈａｉｎ ｗｉｔｈｉｎ ｔｈｅ Ｌｕｚｏｎ Ｓｔｒａｉｔ ｉｓ ｉｍｐｏｒｔａｎｔ

ｉｎ ｍｏｄｅｌｉｎｇ Ｋｕｒｏｓｈｉｏ ｉｎｔｒｕｓｉｏｎ．Ｔｈｅ ｕｓｅ ｏｆ ｃｕｒｖｉｌｉｎ—

ｅａｒ ｇｒｉｄｓ ａｌｌｏｗｓ ｕｓ ｔｏ ｂｅｔｔｅｒ ｒｅｓｏｌｖｅ ｔｈｅ ｒｅｇｉｏｎｓ ｏｆ ｓｔｅｅｐ

ｔｏｐｏｇｒａｐｈｙ ａｎｄ ｉｎｔｅｎｓｅ ｍｅｓｏｓｃａｌｅ ｖａｒｉａｂｉｌｉｔｙ ｗｉｔｈ ｒｅｌ－

ａｔｉｖｅｌｙ ｌｅｓｓ ｃｏｍｐｕｔａｔｉｏｎａ１ ｌｏａｄ ｔｈａｎ ｔｈｅ ｒｅｃｔａｎｇｕｌａｒ

ｇｒｉｄｓ．Ｔｈｅ ｍｏｄｅｌ ｇｒｉｄｓ ｈａｖｅ ｈｉｇｈｅｒ ｒｅｓｏｌｕｔｉｏｎ（ａｂｏｕｔ

１３ ｋｍ１ ｉｎ ｔｈｅ ｎｏｒｔｈｅｒｎ ＳＣＳ ａｎｄ ｔｈｅ ｗｅｓｔｅｒｎ ｂｏｕｎｄ－

ａｒｙ ｏｆ ｔｈｅ Ｎｏｒｔｈ Ｐａｃｉｆｉｃ ａｎｄ ｌｏｗｅｒ ｒｅｓｏｌｕｔｉｏｎ（ａｂｏｕｔ

２９ ｋｍ１ ｉｎ ｔｈｅ ｓｏｕｔｈｅｒｎ ＳＣＳ．Ｔｈｅ ＥＴＯＰ５ ｄａｔａ ｓｅｔ

ｐｒｏｖｉｄｅｄ ｂｙ ｔｈｅ Ｎａｔｉｏｎａｌ Ｇｅｏｐｈｙｓｉｃａｌ Ｄａｔａ Ｃｅｎｔｅｒ

（ＮＧＤＣ１ ｉｓ ｕｓｅｄ ｔｏ ｐｒｅｓｃｒｉｂｅ ｔｈｅ ｍｏｄｅｌ ｂａｔｈｙｍｅｔｒｙ

ｔｈｒｏｕｇｈ ｂｉｌｉｎｅａｒ ｉｎｔｅｒｐｏｌａｔｉｏｎ．Ｔｈｅ ｍａｘｉｍｕｍ ｏｃｅａｎ

ｄｅｐｔｈ ｉｎ ｔｈｅ ｍｏｄｅｌ ｉｓ ５０００ ｍ ａｎｄ ｔｈｅ ｍｉｎｉｍｕｍ ｄｅｐｔｈ

ｉｓ １０ ｍ．Ｔｈｅ ｖｅｒｔｉｃａｌ ｓｉｇｍａ ｃｏｏｒｄｉｎａｔｅ ｈａｓ ３０ ｌｅｖｅｌｓ．

ｗｈｉｃｈ ａｒｅ ｌｏｇａｒｉｔｈｍｉｃａｌｌｙ ｄｉｓｔｒｉｂｕｔｅｄ ｗｉｔｈ ｈｉｇｈｅｒ ｒｅｓ—

ｏｌｕｔｉｏｎ ｎｅａｒ ｔｈｅ ｓｕｒｆａｃｅ ａｎｄ ｂｏｔｔｏｍ ｉｎ ｏｒｄｅｒ ｔｏ ｂｅｔｔｅｒ

ｒｅｓｏｌｖｅ ｔｈｅ ｓｕｒｆａｃｅ ａｎｄ ｂｏｔｔｏｍ Ｅｋｍａｎ １ａｙｅｒｓ．

Ｔｈｅ ｍｏｄｅ１ ｉＳ ｉｎｉｔｉａｌｉｚｅｄ ｗｉｔｈ ｔｈｅ ｃｌｉｍａｔｏｌｏｇｉｃａｌ ａｎ—

ａｎａｌ ｍｅａｎ ｔｅｍｐｅｒａｔｕｒｅ ａｎｄ ｓａｌｉｎｉｔｙ ｄａｔａ ｆｒｏｍ ｔｈｅ

Ｗｌ０ｒｌｄ Ｏｃｅａｎ Ａｔｌａｓ ２００１ Ｂｏｙｅｒ ｅｔ ａ１．，２００５１ ｗｉｔｈ ０．２５。

ｒｅｓｏｌｕｔｉｏｎ．Ｓｕｒｆａｃｅ ｗｉｎｄ ｓｔｒｅｓｓ ｉｓ ｏｂｔａｉｎｅｄ ｆｒｏｍ Ｈｅｌｌｅｒ－

ｍａｎ ａｎｄ Ｒｏｓｅｎｓｔｅｉｎ（１９８３）．Ａ ｌｉｎｅａｒ ｒｅｓｔｏｒｉｎｇ ｓｃｈｅｍｅ

ｏｆ ｔｅｍｐｅｒａｔｕｒｅ ａｎｄ ｓａｌｉｎｉｔｙ ｉｓ ｕｓｅｄ ｉｎ ｔｈｅ ｕｐｐｅｒ ５

ｓｉｇｍａ １ｅｖｅｌｓ．ｉｎ ｗｈｉｃｈ ｔｈｅ ｒｅｌａｘａｔｉｏｎ ｔｉｍｅ ｓｃａｌｅ ｉｓ ｓｅｔ

ｔｏ ｂｅ １０ ｄａｙｓ ａｔ ｔｈｅ ｓｕｒｆａｃｅ ａｎｄ ６０ ｄａｙｓ ａｔ ｌｅｖｅｌ ５．

Ｎｏ ｈｅａｔ ｏｒ ｆｌｅｓｈ ｗａｔｅｒ ｆｌｕｘ ｆｏｒｃｉｎｇ ａｒｅ ａｐｐｌｉｅｄ ａｔ ｔｈｅ

ｓｕｒｆａｃｅ ｓｉｎｃｅ ｔｈｅ ｓｕｒｆａｃｅ ｈｅａｔ ａｎｄ ｍａｓｓ ｅｘｃｈａｎｇｅｓ ａｒｅ

ｏｕｔ ｏｆ ｔｈｅ ｓｃｏｐｅ ｏｆ ｏｕｒ ｓｅｎｓｉｔｉｖｉｔｙ ｓｔｕｄｙ．

Ｔｈｅ ｌａｔｅｒａｌ ｆｏｒｃｉｎｇ ｉｓ ｆｒｏｍ ｔｈｅ ｓｉｍｐｌｅ ｏｃｅａｎ ｄａｔａ

ａｓｓｉｍｉｌａｔｉｏｎ（Ｓ０ＤＡ；Ｃａｒｔｏｎ ｅｔ ａ１．，２０００）ｒｅａｎａｌｙｓｉｓ

ｐｒｏｄｕｃｔｓ．Ｗ＿ｅ ｕｓｅ ＳＯＤＡ ｔｏ ｐｒｏｖｉｄｅ ｏｐｅｎ ｂｏｕｎｄａｒｙ

ｉｎｆｏｒｍａｔｉｏｎ ｆｏｒ ｔｈｅ ｒｅｇｉｏｎａｌ ｏｃｅａｎ ｍｏｄｅｌ ｂｅｃａｕｓｅ ｉｔ ｉｓ

ｏｎｅ ｏｆ ｔｈｅ ｒｅｃｏｇｎｉｚｅｄ ｄａｔａ ｓｅｔｓ ｔｈａｔ ｈａｖｅ ｒｅａｓｏｎａｂｌｅ

ｃｉｒｃｕｌａｔｉｏｎｓ ｉｎ ｔｈｅ ＳＣＳ—Ｐａｃｉｆｉｃ ｒｅｇｉｏｎ．Ｆｏｒ ｅｘａｍｐｌｅ．

ｔｈｅ ａｎｎｕａｌ ｍｅａｎ ｂｉｆｕｒｃａｔｉｏｎ ｐｏｉｎｔ ｆｏｒ ｔｈｅ Ｎｏｒｔｈ Ｅｑｕａ－

ｔｏｒｉａｌ Ｃｕｒｒｅｎｔ ｉｓ ａｒｏｕｎｄ １５。Ｎ ｉｎ ｔｈｅ ｕｐｐｅｒ ｌａｙｅｒ．ｃｏｉｎ－

ｐａｒａｂｌｅ ｗｉｔｈ ｔｈｅ ｒｅｓｕｌｔｓ ｏｆ Ｑｕ ａｎｄ Ｌｕｋａｓ（２００３）．Ｕｓｉｎｇ

ｔｈｅ ｃｌｉｍａｔｏｌｏｇｉｃａＩ ｍｏｎｔｈｌｙ ｍｅａｎ ｖａｌｕｅｓ ｏｆ ＳＯＤＡ ｆａｖ—

ｅｒａｇｅｄ ｏｖｅｒ １９９２ ｔｏ ２００１），ａ ｏｎｅ－ｗａｙ ｒａｄｉａｔｉｖｅ ｎｅｓｔｉｎｇ

ｓｃｈｅｍｅ ｐｒｏｐｏｓｅｄ ｂｙ Ｆｌａｔｈｅｒ（１９７６１ ｉｓ ｕｓｅｄ ｆｏｒ ｔｈｅ ｎｏｒ—

ｍａ１ ｃｏｍｐｏｎｅｎｔ ｏｆ ｔｈｅ ｖｅｌｏｃｉｔｙ ｆｉｅｌｄｓ．Ｉｔ ａｌｌｏｗｓ ｄｉｒｅｃｔ

ｃｏｎｎｅｃｔｉｖｉｔｙ ｂｅｔｗｅｅｎ ｔｈｉｓ ｒｅｇｉｏｎａｌ ｏｃｅａｎ ｍｏｄｅｌ ａｎｄ

ｔｈｅ ｓｕｒｒｏｕｎｄｉｎｇ ｃｉｒｃｕｌａｔｉｏｎ，ａｎｄ ｋｅｅｐｓ ｔｈｅ ｓａｍｅ ｓｅａ－

ｓｏｎａｌ ｃｙｃｌｅ ａｔ ｅａｃｈ ｏｐｅｎ ｂｏｕｎｄａｒｙ ａｓ ｔｈａｔ ｏｆ ＳＯＤＡ．

Ａ ｓｐｏｎｇｅ ｌａｙｅｒ，ａｓ ｓｕｇｇｅｓｔｅｄ ｂｙ Ｉｓｒａｅｌｉ ａｎｄ Ｏｒｓｚａｇ

（１９８１１，ｉｓ ｕｓｅｄ ｆｏｒ ａｂｓｏｒｂｉｎｇ ｔｈｅ ｕｎｗａｎｔｅｄ ｒｅｆｌｅｃｔｉｏｎｓ

ａｔ ｔｈｅ ｏｐｅｎ ｂｏｕｎｄａｒｉｅｓ． Ｔｈｅ ｕｐｓｔ】．ｅａｍ ｓｃｈｅｍｅ ｉｓ

ａｄｏｐｔｅｄ ｆｂｒ ｔｈｅ ｏｐｅｎ ｂｏｕｎｄａｒｙ ｃｏｎｄｉｔｉｏｎｓ ｏｆ ｔｅｍｐｅｒ—

ａｔｕｒｌｅ ａｎｄ ｓａｌｉｎｉｔ ｉｎ ｗｈｉｃｈ ｔｈｅ ｐｒｅｓｃｒｉｂｅｄ ｖ ｕｅｓ ａｒｅ

ａｄｖｅｃｔｅｄ ｉｎｔｏ ｔｈｅ ｍｏｄｅ１ ｄｏｍａｉｎ ｆｂｒ ｔｈｅ ｉｎｆｌｏｗ ｃｏｎｄｉ—

ｔｉｏｎ．

维普资讯

No．5

HoNG

ANDWANG

Fi

g．3．Bottomtopograp

h

y(m)udinExp

tE2．Box

A

denotest

heareainwhich

t

hep

lateauaroundDongsha

Islandsisremov

edalongwi

ththeisland．

Lateralopenboundaryco

nditionsarevery

impor—

tan

t

forareg

ionaloceanmodel

toachieverealist

ic

simulations．Theprimaryruleforareasonableopen

boundaryconditionis

，

att

hefirst

order

，

t

heinflow

should

bebala

ncedb

y

the

outflow．Weestim

ated

thevolumefluxthroug

h

theopenboundaryof

this

reg

ionalmodel．Int

heannu

almean

，

thewestward

inflowthroug

htheeastern

openboundary

is33．16

Sv(1Sv=100

m

0

s

一)，

thesouthwardoutflowthroug

h

the

southernopenboundary

is28．34Sv．andthe

nor

thwardoutflowthroug

hthenorthernopenbound

ary

is4．34Sv．Therefore．theinflowisnearl

y

balanced

b

y

t

heoutflows．

2．2

Numericalexpe

riments

Weperform

threenum

ericalexperiments：onecon—

trolrun

，p

lustwonsi

tivit

yrunsfTable1)．Exoer—

imentE0fExp

t

E

01isthecontrolrun

．

inwhich

the

surfacewindforcingandbo

ttomtopograp

h

yarepre

scri

bed．ThepurpoofExp

tE0istoreproducethe

asonalcirculat

ionintheSCS．Sensitivi

t

y

Exp

t

E1

haszerowindstressforcing

during

thewholeintegr

a

tion

，

whichisaimedat

showing

theefectoflateral

fo

rcingonthecirculationint

henorthernSCS．InExp

t

E2

，

weremovet

hep

lat

eauarou

ndDongshaIslandsb

y

adjustingandsm

oot

hing

thebottomtopograp

h

y

in

boxAofFi

g．3

，

whichalsoshowsthemodifiedtopog

827

rap

h

y．Exp

tE2i

su

dtoinvest

i

gatetheinfluenceof

bottomtopograp

h

yonthecirculat

ioninthe

northern

SCS．especiall

y

t

hepathoftheintrudedKuroshio．

Allexperimentsareinitialized

fr

omtheresting

st

atewithidenticallateralboundarycondition

s．Each

experim

entincludes

a3

yearsp

in—up．follow

edb

y

5一

yearhindcastintegrat

ion．During

t

hesp

in—up，

t

he

modelis

forc

edb

y

theclimatolog

icalannualmeanforc—

ing

fields．Aft

ertha

t．themodelis

forcedb

y

t

hecli—

matolog

icalmonthl

ymeanforcing

fields．Thefo

rc．

ing

fieldshavebeendescribedindetailin

subction

2．1．F0r

eachrun．themodelisintegratedundertheir

respectiveconditions

asprescribedinTable

1．Each

model

yearconsistsof

360d

aysf30dayspermonth)，

andday

1correspondsto1Janu

ary．

3．V_alidationofmodelresults

The

t

emporalevolutionof

thevolume—averagedki—

neticen

ergy

fKEloft

hecontrolrunindicates

thatthe

modelhas

reacheds

t

atisticalequilibrium

a

f

terthe3．

yearsp

in—up(fi

gures

notshown)．TheKEalsoshows

clearasonalvariationsovertheh

indcastintegration．

Thesamefeatures

ofKEexistinthetwonsi

t

ivit

y

experim

ents．After

the5

year

’

shindca

stintegration．

themodelhasaquas

i—equilibriumas

onalcycle．The

last

year

’

sout

putsofall

theexperiments

arebelieved

tobereprentative

of

theclimatolog

icalasonalcir—

culat

ionintheSCS．whichwilIbeanal

yzedin

ction

4．

SinceExp

tE0aimstoreproducethereala—

sonalcirculation．modelvalidat

ionisonl

yperformed

forExp

t

E0．Thecomparisonsbetweent

hemodeled

asurfaceelevationfieldsandtho

obtain

ed

fr

om

theT／Paltimetry

data(averaged

from1993to2005)

areshowninFi

g．4．afterremoving

thedomain—

averagedvalueofea

chfield，IntheSCS，

thewinter—

timebasin．．widecycloniccirculationand

t

hesummer．．

t

imedi

polestructure

southeastofVietnam

aresimilar

inthem

odelresults

andtheobrvat

ions．Theinves—

t

i

gationofYangandLiu(2003)indicatedt

hatthere

are

westward—propagating

forcedRossb

ywavesinthe

northernSCS

，

wi

thapropagat

ion

speedofabout5am

s一0

．The

time—long

i

tudediagramofa

surfacehei

g

h

t

Table1．Desi

gnofthenum

ericalexperimen

ts．For

eachrun

，

t

hemodel

isintegrated

from

asta

teofrest

undert

heir

respectivecondi

t

ions

asprescribedbelow．Thelateralboundarycondit

ionsarekep

t

identical

inall

t

heexperim

ents．

维普资讯

828

SENSITIVITYSTUDY

ONCIRCULATIONINNORTHERN

SOUTHCHINA

SEA

100。E105。

E

110。E115。E120。E125。E

Fi

g．4．Themodeled(top)andobrv

ed(bottom)a

surfa

ceelev

ationfields(m)in

winter(1eft)andsummer(ri

g

ht)．Theobrva

tions

，

whichare

obt

a

ined

fromtheT／P

altimetry

data

，

aret

he

a

sonalme

an

ofa

su

rfacehei

g

ht

fro

m1993to2005．The

domain—averagedvalu

eissubtractedfrom

ea

chfieldbeforethep

lotting．The

contour

int

ervalis0．05m．

anomal

y

intheno

rthernSCSfromExp

tE0(fi

gurenot

shownlhasa

similarpatterntot

hatof

YangandLiu

f2003)．Anal

ysofQueta1．f2004)indicated

t

hatt

he

int

era

nnualvariat

ion

oftileLuzonS

traittransporthad

anoppositep

hacomparedwi

t

htheKuroshiotrans—

porteastofLuzon

，

whileKime

ta1．f20041show

ed

thatt

he

v

ari

ationoftheKuroshiot

ransportwashi

g

hl

y

correlatedwitht

heNorthE

quatorialCnrrentfNECl

bifurcationlatitude．There

for

e．reprodu

cing

t

heNEC

bifurcationlat

i

tudeisvery

important

forsimulating

theKuroshiointrusionat

theLuzonStrai

t．Inthe

prentstud

y．thedep

th—averagedNECbifllrca

tion

freprentedb

y

t

h

ezerocontourast

ofthePhili

p

p

inesinFi

g．4)occursatt

he

southernmostfnort

hern—

most1

posit

ioninsummerfwinterl，

withi

tsan

nu

alav。

erageat

about

13。Nnearthesurface．Thofeat

ures

areconsis

tentwith

t

heresult

sofQueta1．(2004)and

Kimeta1．f2004)．

Ⅵ绝alsocomparetheannualmeanvolumetra

ns—

portsthroug

h

t

heTaiwanStrait

，

LuzonStrai

t

，

Kari—

VoL．25

ma

t

aStraitandthetran

sport

ofthewesternbound．

a

rycu

rrentof

theSCS，Kuroshio

e

ast

ofLuzonIs—

land

，

and

t

heMindanaoCurrentwit

h

previouss

t

ud．

iesfTable21．Generalagreements

existinterms

of

exchangesbet

weentheSCSandt

hesurroundingw

a

ters

，

andintermsof

t

hetransportoftheNort

hPacific

wes

t

ernboundarycurrents．F

orexamp

le

，

the

annual

meanvolumetransportt

hroug

htheLuzonStrai

tin

themodelis5．44Sv．whichiscomparable

with

t

here．

sultofMetzgerand

Hurlbu

rt(1996)，Qu

eta1．(2000)，

andFangeta1．f2005)．Ac

t

uall

y，

es

timatedvolume

tran

sportthroug

htheLuzonStraitranges

fro

m810

Sv(e．g．，

Huangeta1．，

1994)to23Sv(W

yrtki

，

1961)．

Recentl

y，

usingcurrenta

ndh

y

drograp

hicdata

，

Ti

an

eta1．f20061estimatedthevol

u

metransportt

hroug

h

theLuzonStraittobe63

resolut

ionobrva

tionsare

Sv．Morelong—termhi

g

h—

neededt

oobt

ainmoreac—

curatetran

sportt

hroug

h

theLuzonStrai

t．Thetrans—

port

est

ima

tedb

y

W

yrtki(1961)issm

allert

hanother

stud

ies

，

whichm

ay

bearesultofthefactthatthedata

维普资讯

No．5

HoNGANDⅥ，ANG

Table2．Climatolog

icalannu

almean

volumetra

nsport(Sv

，

1Sv=10。

m

。

(TWS)，

LuzonStrait(LS)，

KarimataStrai

t(KS)，

t

hewes

ternbou

ndary

Mindan

a

o

current(MC)．Thetranspor

tinthe

e

astward(westward)and

(negat

ive)．Rfden

otesthereferencedep

t

hof

thed

ynamic

calculations．

829

s

-1)of

theflowsthroug

htheTaiwanStrait

current

ofSCS(WB)，

Kuroshio(KU)，

and

nor

thward(southward)direct

ionispositiv

e

theyudcamemainl

y

fromsurface

shi

p

dri

f

tandsur—

facewinddata．OortransportestimatesofKuroshio

andMindanaoCurrentarevervclototho

ofNi—

tanif19

72)andMetzgerandHurlburt(1996)butnot

as

consis

tentwi

t

htheKuroshiotran

sportobtainedb

y

Queta1．(1998)．Suchadi

fierence

，

according

toToole

eta1．f19901，

stilllieswi

thinthereasonablerangeof

suchest

imates．

Tosu

mmarize，thecomparisonslendconfidence

tothesuccessoft

hemodelinreproducing

the

asonal

circulationint

heSCSandthesuccessof

t

heopen

boundaryconditionsinthisreg

ionaloceanm

odel．

4．An

al

ysis

4．1Seasonalcirc

ulationinthenorthe

rnSCS

Theresul

tsofthecontrolrunfExp

tE0)areudt

o

anal

yzetheaso

nalcirculationint

henorthernSCS．

Thevelocit

yat50一mdep

t

handa

surfaceelevation

fieldsare

showninFi

gs．5aand

6a．respectivel

y．In

winter

，

thecycloniccirculationisdominant，

wi

t

ha

strongslopecurren

tflowingsout

hwes

twardl

yalong

the

northwes

terncont

inentalslopeandamesoscalecy—

clonicedd

ynorthwestofLuzonIsland．Abranchof

theKuroshiointrudesintot

heSCS

fromthesouth—

ernpartoftheLuz

onStrai

tandisblockedb

y

the

cont

inen

talshelfnearDongshaIslands．Aft

erthecol—

lision

，partof

t

heintruded

Kuroshioveersnorthe

ast—

wardandexitst

heSCSt

hroug

h

t

heTaiwa

nStrai

t

andthe

northernpartoft

heLuzonStrait．whilethe

remainingpartcontinueswestwardalong

theconti．

nentalslope．The

northeastwardSCSWCisrelativel

y

weakerinwintert

hanint

heotherasons．Thereis

ahi

g

hasurface

elevationbel

tbetweentheSCSWC

andthe

slopecurrent．The

northeastwardasurfa

ce

slope

along

t

hesou

theastChinacoastisident

icalt

o

theobrvationsofFangandZhaof1989)．Insum—

mer

，

t

hereisarelativel

yweakcyclonicgyreinthe

deeppar

tof

thenorthwesternSCS．Pohlmannf19871

suggestedthatt

hisgyrew

asinducedb

y

baroclinicef

fects．Thecurren

tsonthecontinentalshelfarestrong

andconsistentl

y

flown

ort

heastward．Thecon

tours

of

asurfaceelevat

ionon

theshelfarelargel

yparallel

withthecoastline

，

andthehi

g

hasurface

elevat

ion

beltdropsgraduall

yasitext

endswestwardalong

t

he

outered

geof

t

hecontin

entalshelf．S

pringandaut

umn

arethetransitionperiods

fo

rt

hereg

ion．TheSCSWC

is

streng

thenedinspringasthewindchangesfrom

northeas

terl

y

to

so

ut

hwes

terl

y．Thesimula

tedcircu．

1at

ionpatternagr

eesrat

herwellwi

t

h

the

schemat

ic

patternsofFangeta1．f19981forbothsummerand

winter．

Thevert

ical

profilesofthenorm

alveloci

t

yalong

theacross．shelftranct

inthenorthernSCSfshown

inFi

g．1b)areprentedinFi

g．7a．Thepositive(neg

ativelvaluecorrespondsto

thenor

theastward(south．

westwardlalong—shoreflow．The

as

onalvaria

tions

of

theflowareobviou

sin

the

upper400m

，

whilethe

alongs

lopeflowisrelative

l

ystableint

hedeeperlayer．

Intheinnershelfreg

ion．thecu

rrentsshowdirectre—

spons

tothemonsoonreversal．Thenort

heastward

SCSWCisnarrowl

yconfinedattheoutered

geofthe

cont

inentalshel

finwinter

andautumnandbecomes

widera

ndstrongerinspringandsu

mmer．Thereisa

year—roundnort

heastward

flowaround1400一mdep

th

，

who

m

aximumvelocit

y

is1arger

than0．1ms

1

．

Thisflowmay

berelat

edtothe

outflowoft

hewater

fr

omtheSCStot

heNort

hPacifict

hroug

ht

heLuzon

Strai

t

，

whichwasnotedb

yQueta1．(2000)andTian

et

a1．f20061．

Mored

ynamicinsi

g

htcanbe

obtainedb

yexam．

ining

thehorizontal

pressuregradientfields．Fi

gures

8a

and9apren

tthehorizontal

pressuregradient

at

50一mdep

thint

heeast—west(z)andnorth—south(Y)

directions

，

respec

tivel

y．Thehorizon

tal

pressu

regra

dientisdefinedas

瓦

O

p

=旦

Ox

ifzpg

dz

t

=p(呐g鼍+fzg篆耐

维普资讯

830SENSITIVITYSTUDY0NCIRCULATIONINNORTHERNSOUTHCHINASEA

Fi

g．5．SeaSonalmeanvelocit

y

fields(ms

一)at50一mdep

t

h

for(a)Exp

tE0(controlrun)，(b)Exp

t

E1(withou

t

surfaceforcing)，(c)diferencebetweenExp

ts

EOandE1(Exp

tEOminusExp

t

E1)，

and(d)Exp

tE2(removing

thep

lateauarou

ndDongshaIsland)．

维普资讯

N0．5

HoNGANDⅥ硝。NG

Fi

g．5．(Continued)

831

维普资讯

832

SENSITIVITYSTUDYONCIRCULATIONINN

ORTHERNSOUTH

CHINA

SEA

VOL．2

5

110~E114~E118~E122。E110~E114。E118~E122。E110~E114~E118~E122。E

110~E114~E1180E122~E

110。E114。E118~E122。E110~E114。E

118~E122。E110~E114。E118~E122。E110~E114~E118~E122~E

110~E114。E118。E122。E110~E114。E118~E122。E110~E114。E118~E122。E

110~E114~E118~E

122。E

110~E114。E118。E122。E110~E

114。E118~E122。E110~E114~E118~E122。E

110~E114~E118~E122。E

Fi

g．6．Seasonalmeanasurfaceeleva

tion(m)f

or(a)Exp

tE0

，(b)Exp

tE1

，(c)difere

ncebetweenExp

t

sE0andE1

(Exp

tE0minusExp

tE1)，

and(d)E2

，

a

f

terremoving

theirdoma

i

n

averagedvalues．Thecontourint

erval

i

s0．05m．

where

th

epressuregradientsinxand

Y

directionsare

reprented

b

y

t

hesubscri

p

tsi=1and2．respect

ivel

y．

Intheequa

tion

，P

ispressure

，P

isdensit

y，9

isgravi

t

y，

and"istheasurfaceelevat

io

n．Itiswellknowntha

t

t

hereisnumericalerrorinthepressuregr

adientcalcu—

lat

i

onoveras

t

eep

t

opograp

h

y

inthe

terrainfollowing

oceanmodelfe．g．，Mellor

eta1．，1998)．Thisnu

merical

errorcan

not

becomp

letel

yeliminated38longasthe

grid

does

no

tfollowgeopot

entialorisopycnal

surfaces．

In

orderto

redu

cethirrortoanaccep

tablelevel(be一

10wother

nu

m

ericalerrorslveralmethodshavebeen

sugges

ted(e．g．，

ChuandFa

n

，

2003

；

Mellore

t

a1．，

1994

；

Stellingandv

anKes

ter

，

19941．Among

the

，

t

hree

stepsare

adop

tedinou

r

calcula

tions．First．thebot—

tomtopograp

h

y

issli

g

htl

ysmoo

thedtorem

ov

esharp

topograp

hicvaria

tionsbe~restarting

then

umeri

cal

simulations．Second

，

thehorizontall

yaverageddensit

y

hasbeen

subtrac

t

ed

fromp

be

for

et

hecalculat

ions

，

andtheremainingpartisreprentedb

y

P

’

．Third

，

t

hegridischa

ngedfromasi

gmagridt

oaz—level

gridbeforecalcula

ting

thehorizon

t

al

pressuregradi—

ent．Thestepshavebeenproventobe

e

ficient

in

reducing

thepressu

regradient

error．The

w

estw

ard

(eastw

ard)pressuregrad

ientcorrespondstot

heposi—

tivefnegativelvalueinFi

g．8a

，

whilet

he

sout

hward

(northward)pressuregradientcorrespondstothepos—

itive(negat

ive)valueinFi

g．9a．AsFi

g．8a

show

s

，

the

westward

pressuregradientsoccupy

thenort

heastern

SCS

throug

houtt

heyearexcep

t

int

he

areasouth—

westofTaiwanIsland．Thee

astw

ard

pressu

regradi—

entsinthenorthwesternSCSshowobviou

sa

sonal

variations

，

whicharestrongerinwinteranda

u

tumn

thaninspringandsumm

er．Int

heLuzonStrait

，

the

wes

t

ward

pressuregradientsarerelativel

y

h

i

g

herini

ts

southernpartthanthat

initsnorthernpart．Theeast—

ward

pressuregradientso

ccupy

t

hereg

ion

southwest

维普资讯

N0．5

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、，

工

在

o

o

Lat(oN)

HoNGAND、^，ANG

Fi

g．7．Verti

cal

profileoftheveloci

t

y(ms

_)normaltotheacross—shelf

tranct

int

henort

hernSCS

(showninFi

g．1b)for(a)Exp

tEO

，(b)Exp

t

E1

，(C)diferencebetweenExp

tE0andE1(Exp

t

E0minus

Exp

tE1)，

and(d)E2．Thepositive(negative)valuecorrespondstot

henortheastward(southwestward)

flow．Thecounterintervalis0．05ms。

．

833

维普资讯

834

24。N

220N

20。N

180N

160N

24。N

220N

20口N

18

0N

16~N

240N

220N

20。N

180N

160N

240N

220N

20~N

180N

160N

a

SENSITIVITYSTUDYoNCIRCULATIoNINNORTHERNSoUTHCHINASEA

VOL．25

109。E1120E115。E118。E121。E124。E109。E1120E115。E118。E121。E124。E

109~E112。E115。E118。E121。E124。E109。E112~E115。E1侣。E121。E124。E

b

109。E112~E115。E118。E121。E124。E1

09。E"20E115。E118。E121。E124。E

109。E1120E115。E118

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E121

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109。E1120E115~E118。E121。E124。E109。E112。E115。E1180E121。E124。E

109。E1120E115。E118。E121。E124。E109。E1120E115。E118。E121。E124。E

d

109~E112~E115~E1180E121。E124。E109。E112。E115~E1t8。E121。E124。E

109~E112

~

E115。E”8。E121

。E124。E109~E112。E115。E118。E121

。E124。E

．柏．30—20t0010

203040

Fi

g．8．Fieldsofhorizontal

pressu

regradients(k

gm

1

s

q)intheea

st—west

directionat50一mdep

t

h

for(a)Exp

tE0

，

fb)Exp

tE1

，fc)diferencebe

tweenExp

tE0andE1(Exp

tE0minusExp

tE1)，

and(d)Exp

t

E2．Theboldlinesare

zerocontours

，

andt

hedashed(solid)linesreprentnegat

ive(positive)values．Thecontourintervalis4×10“k

gm

。

s．

ofTaiwanIslandall

yearround．whichmay

beregu—

latedb

y

thetopograp

h

yandintrudedKuroshiowa

ter．

InFi

g．9a．thesouthwa

rd

pressuregradient

isdomi—

nantalongazonalbel

tt

hatislargel

yalong

thecont

i—

nentalslopesou

thwestofDongshaIslands

，

whereas

thenort

hward

pressuregradientoccup

iest

heouter

ed

geoft

hecontinentalshelfwithclear

as

onalvaria

t

ions．Themeridional

pressuregradientsareopposi

te

inthesout

hernandnorthernpartsoftheLuzonStrait

，

whichcorrespondstot

heexcursionsofKuroshiointhe

straj

t．

4．2Efects

oflateralfo

rcing

Thelateralforcing

throug

hthestrai

ts

，

especiall

y

thothroug

ht

heLuzonStraitandTaiwanStrait

，

has

animportantefectonthecirculationint

henorthern

SCS．Forthepurpoof

quali

f

y

ing

thee

fects

，

weu

thensi

t

ivit

y

Exp

tE1wi

t

h

t

heforcingonl

yatt

helat—

eralopenboundary．Thevelocit

yat50．mdep

t

hand

asurfaceelevationfieldsareshowninFi

gs．5

band

6b

，

respect

ivel

y．I

t

isshownt

hatwithoutthesurface

forcing，thecirculat

ionsouthof18。Nisveryweak

，

and

t

heLCEdisappears．ThereisabranchoftheKuroshio

thatintrudesinto

theSCSand

flowswestwardalong

thecont

inentalslopeall

yearround．Astead

ycur—

rentflowsnort

heastwardalong

theout

ered

geof

t

he

continentalshelf，

whichcomparesfavorabl

ywiththe

obrvedSCSWC．Thevert

ical

profilesof

t

henormal

velocit

yalong

t

heacross—shelftranctfFi

g．7b)indi—

ca

tes

thattheSCSWChasanobviousbarotrop

ic

fea

ture．Ahi

g

hasurfaceelevat

ionbeltexistsbetween

t

heslopecurrentandtheSCSWC．

whichdecreas

维普资讯

No．5HONGAND

Ⅵ，ANG

fromeasttowest．Thereareonshoreflowsbetween

t

heslopecurrentandtheSCSWC，

whichsuggeststhat

theslopecurrentmi

g

h

t

feedtheSCSWCt

hroug

h

t

he

onshoreflow．Thisnsitivi

t

yrunrevealsthatthehi

g

h

asurfaceelevat

ionbeltalong

thecont

inentalshelf

breakm吖beinducedb

y

theKuroshiointrusion

throug

htheLuzonStraitand

t

heoutflowthroug

h

t

he

TaiwanStraitforlateralforcing

throug

htheLuzon

andTaiwanStrai

t)，

andthegenerationoftheSCSWC

isclol

yrelatedwi

t

h

t

heSCSBKthroug

htheimpod

pressureheadandtheonshoreflowinthecont

inen—

talshelfbreakreg

ion．TheannualmeanLuzonStrait

transportinExp

t

E1

is5．4Sv．whichisverycloto

thatint

hecontrolrun(Table2)．Thisindicatest

hat

，

al

t

houg

hthewindforcing

hascontribu

tiontothea

sonalvariation

of

theLuzonStraittransport．ithas

littleefectontheannualmeanLuzonStrai

ttrans—

port．Thisisconsistentwi

t

h

thefindingofMetzger

andHurlburtf1996)．ThetransportsintheTaiwan

Strait

，

MindoroStrai

t

，

andKarimandaStraitare1．46．

2．98，

and

0．78Sv

，

respectivel

y．Theinflowandoutflow

throug

hallthestrai

tsarenearl

y

balanced．From

am

assbalancepoint

ofview

．t

hemeanLu—

zonStraittransportisactuall

yawestwardextension

ofthenortherntrop

ical

gyreintheWestPacificr

Met—

zgerandHurlburt

，

1996)．AsFi

g．8bshows

，

thepres—

suregradientfieldsintheLuzonStrait

calculated

frpin

Exp

tE1havesimilarpatternswi

t

h

thofr

omExp

t

E0．Thewestward

pressuregr

adient

occup

iesmostof

thenorthernSCS．Fi

gure9brevealsthatt

hesouth—

ward

pressuregradientisrelat

ivel

ystrongerinthe

northeastSCSthanthatinthenort

hwestSCS．which

correspondstothegradualweakeningof

t

hewestward

flowasi

treachest

heinterioroftheSCS．Thenorth—

ward

pressuregradientxistconsistent

l

yonthecon—

tinentalshelfandarequitestablea11

yearround．

4．3Efects

ofwindfo

rcing

Wedemonstratetheefect

ofwindforcingonthe

circulationb

yshowing

thedi

fieren

cebetweenExp

ts

E0andE1．Thediferencesofthevelocit

yat50．．m

dep

thandasurfaceelevationfieldsareprentedin

Fi

gs．5cand

6c

，

respectivel

y．Itisshownthat

，

ex—

cep

ttothewestoftheLuzonstraitandthecontinen

talshelfbreakreg

ion

，

thecirculationsinthenorthern

SCSshowsimilarpatternstot

hoinFi

gs．5aand

6a．In

wint

er

，

thecyclonicgyreoccup

iesthewholebasin

，

andtheLCEexistswest

of

Luzon．TheEkmandri

f

t—

inducedwaterp

ilesupalong

thecoast．whichcreat

es

thea

cross—shelfasurfaceslopenearthecoast．The

currentsintheshallowwaterflowconsistentl

ysouth—

westward．ThesouthwestwardSCSwesternbound—

arycurrentismaintainedin

springandautumn

，

with

mesoscaleeddiesappearing

inthedeepa．The

835

features

are

mainl

y

theresul

tofwind

forcing．Ithas

beenshowninpreviousst

udiesfe．g．，

Su

，

2004)that

summermonsoonfo

rcesthecurrentsinthenort

hern

SCScontinentalshelftoflownortheastward．However．

itcanbenotedinFi

g．5ct

hattherearealmostno

leewardfnort

heastwardlcurrent

sont

heshelfinsum—

mer．Thevertical

profilesofthenormalvelocit

yalong

theacross—shelftranct

inthenorthernSCSalsore—

vealthatt

hesimulatedwind—inducedalongshelfflow

isveryweakinsummer．Thereasoncanbe

exp

lained

asfollows．AsExp

tE1shows．theKuroshiointrusion

caninduceahi

g

hasurfaceelevationbelt

andthe

relatednortheastwardcurrentint

hecontinentalshelf

(Fi

gs．5band

6b)．MetzgerandHurlburt(1996)sug

gestedthatt

hepressureheadcreatedb

y

thep

ileupof

waterfr

omthesouthwestmonsoonwouldreducethe

LuzonStraittransport．Wi

t

houtwindforcing．theLu—

zonStraittransportfwhichiswestwardlsimulatedin

Exp

tE1ixaggeratedinsummer．thus．theintruded

Kuroshioisstrongerthant

hatinExp

tE0．There—

fore

，

thecirculationinthenorthernSCScontinental

shel

f／slopesimulatedinExp

tE1issomewhat

over—

est

imatedinsummer．Asaresult．thewind—induced

circulat

ionob

tained

fr

omthediferencebetweenExp

ts

E0andEl

，

isunderestimatedinsummerfFi

gs．5cand

6c)．Thevertical

profilesofthealongshelfveloci

t

y

in

theacross—shelftranctfshowninFi

g．1b1indicate

thattheSCSWCtotall

y

disappearsinthixperiment

(Fi

g．7c)．

Thewind—inducedhorizontal

pressuregradient

fieldsat50一mdep

t

hareshowninFi

gs．8cand9c．

whichareintheeast．westandnorth．sout

hdirections．

respect

ivel

y．Itisshownthattherearetwohi

g

hwest—

ward

pressuregradientreg

ionsint

henorthernSCS：

oneoccurswest

of

t

heLuzonIsland，t

heotherlies

southwestofTaiwanIslandfFi

g．8c)．Theeastward

pressuregradientsalong

thenorthwesternboundaryof

thebasinshowsimilarpatternsasthoinFi

g．8a

，

and

have

obviousasonalvariat

ions．Suchvariations

are

consistentwith

t

hetransi

t

ionofthem

onsoon．The

pressuregradientsinthenort

h—southdirect

ionfFi

g．

9c)showvery

di

fierent

featuresthant

hointhe

ot

her

experiments．Thereisnozonalbel

tofsout

hwardhi

g

h

pressuregradientwestoftheLuzonStrai

t．Instead

，

t

hereare

southwardhi

g

h

pressuregradientsalong

the

northwesternboundaryofthebasin

，

whichistheresult

of

thewat

erp

ileupalong

thenorthwesternboundary

inducedb

y

thewind．Thereisnonorthward

pressure

gradientonthenorthernSCScont

inentalshelf．

4．4Efects

ofbottomtopograp

h

y

Severalstudiessuggestedthatt

heintruded

Kuroshiowasdeflect

edb

y

thecontinentals10penear

DongshaIslands(e．g．，

zhong，

1990

；

Hsuehandzhong，

维普资讯

836

24~N

220N

200N

18~N

16~N

240N

220N

20~N

180N

16口N

24~N

22~N

20~

N

18~N

f60N

24~N

22~N

200N

1BoN

160N

a

SENSITIVITYSTUDYONCI

RCULATIONINNORT

HERN

SOUTHCH

INA

SEA

b

109。E1120E115。E118。E121

。

E124。E

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4030