海平面上升，世界上的主要沿海城市可能被淹没

Rising seas could affect three times more people by 2050 than previously thought, according to new research, threatening to all but erase some of the world’s great coastal cities.

一项最新研究显示，到2050年，海平面上升对人类的影响将是之前预计的三倍，这可能会几乎抹掉世界上一些最重要的沿海城市。

The authors of a paper published Tuesday developed a more accurate way of calculating land elevation based on satellite readings, a standard way of estimating the effects of sea level rise over large areas, and found that the previous numbers were far too optimistic. The new research shows that some 150 million people are now living on land that will be below the high-tide line by midcentury.

在周二发表的一篇论文中，作者开发了一种更精确的、基于卫星读数的陆地高程计算方法，这是估计大面积海平面上升影响的标准方法，他们发现之前的数据过于乐观。新的研究表明，到本世纪中叶，约有1.5亿人将生活在海平面以下的陆地上。

Southern Vietnam could all but disappear.

越南南部可能会完全消失。

More than 20 million people in Vietnam, almost one-quarter of the population, live on land that will be inundated.

越南有2000多万人口生活在即将被淹没的土地上，几乎占总人口的四分之一。

Much of Ho Chi Minh City, the nation’s economic center, would disappear with it, according to the research, which was produced by Climate Central, a science organization based in New Jersey, and published in the journal Nature Communications. The projections don’t account for future population growth or land lost to coastal erosion.

由新泽西州的科学组织气候中心(Climate Central)所做的这项研究，发表在《自然通讯》(Nature Communications)期刊上。它称，越南的经济中心胡志明市的大部分地区将随之消失。这些预测没有考虑未来的人口增长或海岸侵蚀造成的土地损失。

Standard elevation measurements using satellites struggle to differentiate the true ground level from the tops of trees or buildings, said Scott A. Kulp, a researcher at Climate Central and one of the paper’s authors. So he and Benjamin Strauss, Climate Central’s chief executive, used artificial intelligence to determine the error rate and correct for it.

论文作者之一、气候中心研究员斯科特·A·库尔普(Scott a . Kulp)说，使用卫星进行的标准高程测量很难区分真实的地面高度与树木或建筑物的顶部。因此，他和气候中心的首席执行官本杰明·施特劳斯(Benjamin Strauss)使用人工智能来确定错误率并进行校正。

In Thailand, more than 10 percent of citizens now live on land that is likely to be inundated by 2050, compared with just 1 percent according to the earlier technique. The political and commercial capital, Bangkok, is particularly imperiled.

在泰国，超过10%的居民现在生活在可能在2050年被淹没的土地上，根据早期的技术，这个比例只有1%。政治和商业首都曼谷尤其岌岌可危。

Climate change will put pressure on cities in multiple ways, said Loretta Hieber Girardet, a Bangkok resident and United Nations disaster risk-reduction official. Even as global warming floods more places, it will also push poor farmers off the land to seek work in cities.

联合国减灾官员、曼谷居民洛蕾塔·希伯·吉拉德特(Loretta Hieber Girardet)表示，气候变化将在多个方面给城市带来压力。全球变暖淹没了更多的地方，而且还将迫使贫穷的农民离开土地到城市寻找工作。

“It is a dire formula,” she said.

“这是一个可怕的公式，”她说。

In Shanghai, one of Asia’s most important economic engines, water threatens to consume the heart of the city and many other cities around it.

上海是亚洲最重要的经济引擎之一，水患正威胁侵蚀它的心脏地带及其周边的许多城市。

The findings don’t have to spell the end of those areas. The new data shows that 110 million people already live in places that are below the high tide line, which Mr. Strauss attributes to protective measures like seawalls and other barriers. Cities must invest vastly greater sums in such defenses, Mr. Strauss said, and they must do it quickly.

该发现并不意味着这些地区的末日。新的数据显示，已经有1.1亿人生活在涨潮线以下的地方，斯特劳斯将其归因于海堤等防护措施。施特劳斯说，城市必须在这类防御措施上投入大量资金，而且必须尽快。

But even if that investment happens, defensive measures can go only so far. Mr. Strauss offered the example of New Orleans, a city below sea level that was devastated in 2005 when its extensive levees and other protections failed during Hurricane Katrina. “How deep a bowl do we want to live in”? he asked.

但即使投资到位，防御性措施也只能起到这么大的作用。斯特劳斯以新奥尔良为例，这座低于海平面的城市在2005年遭到了毁灭性的破坏，原因是在卡特琳娜飓风(Hurricane Katrina)来袭时，它大面积的防洪堤和其他防护设施都失灵了。“我们想住在口多深的碗里?”他问道。

The new projections suggest that much of Mumbai, India’s financial capital and one of the largest cities in the world, is at risk of being wiped out. Built on what was once a series of islands, the city’s historic downtown core is particularly vulnerable.

新的预测显示，世界上最大的城市之一、印度金融中心孟买的大部分地区有被摧毁的危险。这座城市的市中心拥有悠久的历史，其核心地带过去曾是一系列岛屿，如今格外脆弱。

Over all, the research shows that countries should start preparing now for more citizens to relocate internally, according to Dina Ionesco of the International Organization for Migration, an intergovernmental group that coordinates action on migrants and development.

协调移民和发展行动的政府间组织国际移民组织(International Organization for Migration)的黛娜·约内斯科(Dina Ionesco)说，总的来说，研究表明，各国现在应该开始为更多居民在国内重新安置做好准备。

“We’ve been trying to ring the alarm bells,” Ms. Ionesco said. “We know that it’s coming.” There is little modern precedent for this scale of population movement, she added.

“我们一直试图敲响警钟，”约内斯科说。“我们知道它就要来了。”她还说，这种规模的人口流动在现代几乎没有先例。

The disappearance of cultural heritage could bring its own kind of devastation. Alexandria, Egypt, founded by Alexander the Great around 330 B.C., could be lost to rising waters.

文化遗产的消失也会造成损失。埃及的亚历山大市由亚历山大大帝在公元前330年左右建立，它可能会被上升的海水淹没。

In other places, the migration caused by rising seas could trigger or exacerbate regional conflicts.

在其他地方，海平面上升引起的迁移可能引发或加剧区域冲突。

Basra, the second-largest city in Iraq, could be mostly underwater by 2050. If that happens, the effects could be felt well beyond Iraq’s borders, according to John Castellaw, a retired Marine Corps lieutenant general who was chief of staff for United States Central Command during the Iraq War.

到2050年，伊拉克第二大城市巴士拉可能会被淹没。退役海军陆战队中将、曾在伊拉克战争期间担任美国中央司令部参谋长的约翰·卡斯特洛(John Castellaw)表示，如果这种情况真的发生，其影响可能会远远超出伊拉克的边界。

Further loss of land to rising waters there “threatens to drive further social and political instability in the region, which could reignite armed conflict and increase the likelihood of terrorism,” said General Castellaw, who is now on the advisory board of the Center for Climate and Security, a research and advocacy group in Washington.

因为海平面上升而进一步损失土地，“可能促进该地区社会和政治不稳定，从而引发武装冲突，增加恐怖主义的可能性，”卡斯特洛表示，他目前是华盛顿研究和游说团体气候与安全中心(Center for Climate and Security)的顾问委员会成员。

“So this is far more than an environmental problem,” he said. “It’s a humanitarian, security and possibly military problem too.”

“所以这远远不只是一个环境问题，”他说。“这是人道主义和安全问题，以及可能的军事问题。”