
The sea level around Shanghai has risen 120 millimeters since 1977 - a level higher than the national average.
Many scientists believe rising sea levels are caused by global warming but the city’s continuous land subsidence exacerbates the problem.
"It’s time we took action over rising sea levels," Chen Manchun, an SOA official who takes charge of recording sea levels, told Shanghai Daily.
He said the sea level around the country’s coast had risen by 90 millimeters over the past 30 years and that Shanghai was 30 millimeters above the average.
He said sea levels were rising faster than at any time in history but due to the lack of statistics it is not known exactly how much sea levels rose prior to 1977.
At the same time, the city is sinking by about seven millimeters every year, partly due to the overuse of underground water and the rapid urban construction.
Chen said the rising sea level could cause sea water to flood into inland waters and, in the long run, lead to climate change which would affect farming and fishing.
He suggested the city government limit the construction of highrises to reduce the factors contributing to land subsidence. He also said the city government needed to raise its flood control walls on a regular basis.
Shanghai has more than 4,000 buildings over 18 stories and many more are under construction.
上海海平面涨速快了点
上海沿海海平面上升的速率,不仅高于全国沿海海平面上升速率,也高于所在的东海海平面平均上升速率。记者昨天从国家海洋局东海预报中心了解到,根据监测数据,上海沿海海平面平均上升速率约为3.8毫米/年。如果按照这一速度计算,未来10年上海的沿海海平面将上升38毫米左右,与国家海洋局对我国未来10年沿海海平面上升的预测数据相比,这一数字属于较高的区间。
我国沿海海平面上升速率不仅高于全球平均,并且不同区域的上升速率差别也很大。上海市海洋环境预报台副主任龚茂珣昨天接受记者采访时表示,沿海海平面上升的主要原因是全球气候变暖导致海水膨胀、冰川与极地冰盖融化造成的。我国的海温资料分析表明,近30年来,我国沿海气温上升1.1℃,海温上升 0.9℃,海水温度上涨是海平面上升的直接原因。
“大城市的地面沉降也是造成海平面上升更突出的原因之一。”龚茂珣认
为,像天津、上海这样的大城市,因为位于河口淤积平原,地面存在压实效应。
2006年以来,上海对海洋环境的监测布点更加密集,沿海新建了3个海洋环境监测站,使得上海海洋环境监测站的数量增加到11个,可以收集到更多的监测数据和进行更为全面的海平面上升预测分析。龚茂珣认为,应该从一个较长的周期来看待沿海海平面的变化。我国近50年来沿海海平面呈波动上升趋势,上升速度高于全球沿海海平面平均上升值,其中长江三角洲、珠江三角洲和环渤海地区上升速度更快。预计未来10年,中国沿海海平面将继续保持上升趋势,将比2007年上升32毫米,沿海地区海平面上升幅度介于18-39毫米之间。
根据国家海洋局最新发布的2007年《中国海平面公报》,2007年中国沿海海平面平均上升速率为2.5毫米/年,高于全球海平面1.8毫米/年的上升速率,而东海的上升速率则高于渤海、黄海和南海,达到3.1毫米/年。
《公报》显示,中国沿海海平面上升“北快南缓”的趋势十分明显。近30年来,天津沿岸海平面上升最快,为196毫米,上海次之为115毫米,辽宁、山东、浙江上升均在100毫米左右,福建、广东较低为50-60毫米。
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Shanghai sea levels rise faster than average
上海海平面涨速快了点