摘要: |
通过对浙江沿海及长江口31个潮位站同步潮位数据分析比较可知,浙江沿海各站的潮汐变化有着较好的一致性和明显的规律,即在半个月的潮汐周期中出现1次大潮和1次小潮,而在1个太阴日中,出现2次高潮和低潮,潮汐变化过程呈现出半日潮特征。在河口区,落潮历时长于涨潮历时,且由河口口门向上游历时差逐渐增大;在近岸浅海区,长江口至浙中沿海的大目涂站,表现为落潮历时长于涨潮历时;向南至浙中沿海的东矶岛、大陈岛站涨落潮历时基本相等;总的来说浙南沿海松门、披山岛、坎门、洞头站涨潮历时略长于落潮历时;而南麂岛、琵琶门和霞关站又以落潮历时略长于涨潮历时为特点。在近岸浅海区,潮差分布从长江口往南到霞关总的趋势由北向南增大。在河口区,最高潮位和平均高潮位由河口向上游逐渐增大;在近岸浅海区,最高潮位和平均高潮位由北向南增大,最低潮位和平均低潮位的分布则恰好相反。 |
关键词: 潮位 潮差 涨落潮历时 浙江沿海 长江口 |
DOI: |
分类号:P731.23 |
基金项目:国家自然科学基金资助项目(51109188);浙江省科技条件专项(2060503);浙江省科技计划项目(2016F10012,2017F10008);浙江省水利科技计划项目(RC1605) |
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Comparative analysis of synchronous tidal data from Zhejiang coast and Yangtze River estuary |
TANG Dongyue, ZHANG Shenyang, HE Wenliang
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Zhejiang Surveying Institute of Estuary and Coast, Hangzhou
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Abstract: |
The comparative analyses of the synchronous tidal data obtained from 31 tidal level stations located at the Zhejiang coast and the Yangtze River estuary show that there is a good consistency and obvious regulation of the tidal variation in this area. The spring and neap tides both occur once in a half a month tidal cycle, and the high and low tides occur twice in a lunar day, so the tidal variation process presents the semidiurnal tidal characteristics. In the estuary, the ebb tide duration is longer than the flood tide one, and the ebb tide duration becomes longer from the estuary to the upstream. In the nearshore shallow water from the Yangtze River estuary to the Damutu tidal level station located at the middle coast of Zhejiang Province, the ebb tide duration is also longer than the flood tide one. The flood and ebb tide durations are almost equal at the stations of Dongji and Dachen islands of the Zhejiang coast. Along the south coast of Zhejiang Province, the flood tide duration of Songmen, Pishan island, Kanmen and Dongtou stations is a little longer than the ebb tide one, but it shows an opposite characteristic of Nanji island, Pipamen and Xiaguan stations. In the nearshore shallow water from the Yangtze River estuary down to Xiaguan, there is a trend that the tidal range distribution gradually increases from the north to the south. In the estuary, the maximum and mean high tidal levels become larger from the estuary to the upstream. And the maximum and average tidal levels become larger from the north to the south; however, the distribution characteristics of the minimum and mean low tidal levels are opposite in the nearshore shallow water zone. |
Key words: tidal level tidal range flood and ebb durations Zhejiang coast Yangtze River estuary |