海平面上升的惊人事实

海平面上升的惊人事实

The ocean is coming for us. Global sea levels are now rising by 3.6 millimeters per year, up from an average rate of 1.4 mm per year last century. In just 80 years, the ocean could be more than 1 meter (3.3 feet) taller than it is today.

大海在向我们逼近。目前，全球海平面正以每年3.6毫米的速度上升，而上个世纪的平均速度为每年1.4毫米。仅仅在80年内，海洋的高度就可能超过今天的1米(3.3英尺)。

Up to 216 million people currently live on land that will be below sea level or regular flood levels by 2100. (Photo: Shutterstock)

To help put things in perspective, here's a deeper dive on rising seas:

为了帮助我们正确看待问题，我们来深入研究一下海平面上升:

1. Global sea levels have already risen by 8 inches (200 mm) since 1880.

自1880年以来，全球海平面已经上升了8英寸(200毫米)。

NASA's Earth Observatory

Most of those historical data come from tide-gauge measurements, which are now complemented by satellite observations.

这些历史数据大多来自潮汐测量，现在卫星观测补充了这些测量数据。

2. Not only are sea levels rising; the rate of their rise is rising.

海平面不仅在上升;他们的增长速度正在加快。

This chart shows the rate at which sea-level rise is increasing from year to year. (Image: NASA GSFC)

On average, sea levels rose by 1.4 mm from 1900 to 2000. The yearly pace had surpassed 3 mm by 2010, and now it's up to 3.6 mm per year, according to the IPCC.

从1900年到2000年，海平面平均上升了1.4毫米。政府间气候变化专门委员会(IPCC)的数据显示，到2010年，中国每年的温室气体排放量已经超过了300万立方米，现在已经达到了3.6万立方米。

3. Every vertical inch of sea-level rise moves the ocean 50 to 100 inches inland.

海平面每垂直上升一英寸，海洋就会向内陆移动50至100英寸。

Rising seas worsen regular flooding — like this 2015 high tide in Miami Beach — for many coastal cities. Miami is in the midst of a five-year, $400 million effort to upgrade its stormwater pump program. (Photo: Joe Raedle/Getty Images)

One inch may not sound like much, but it's an extra inch of ocean, not water in a rain gauge. Earth's oceans hold about 321 million cubic miles of water, and are generally more like a bowl than a beaker, with sloping sides. According to NASA, every vertical inch of sea-level rise covers 50 to 100 lateral inches (1.3 to 2.5 meters) of beach.

一英寸可能听起来不多，但它是额外的一英寸海洋，而不是雨量计中的水。地球上的海洋拥有大约3.21亿立方英里的水，通常更像一个碗而不是一个烧杯，有倾斜的边。据美国宇航局称，海平面每垂直上升一英寸，就会覆盖50到100英寸(1.3到2.5米)的沙滩。

4.Sea levels could rise another 1.3 meters (4.3 feet) in the next 80 years.

未来80年，海平面可能再上升1.3米(4.3英尺)。

This map shows areas that would flood (marked in red) due to 1-meter sea-level rise. (Image: NASA)

In its September 2019 report, the IPCC raised its upper projection for sea levels at the end of this century, warning the ocean could rise by 1.1 meters (3.6 feet) before 2100. Some projections go even higher — a 2016 study, for example, suggested global sea levels will likely rise 0.5 to 1.3 meters (1.6 to 4.3 feet) by the end of this century if greenhouse gas emissions aren't rapidly reduced. Even if the 2015 Paris Agreement does spur ambitious climate policy, sea levels are still projected to rise 20 to 60 cm (7.8 to 23.6 inches) by 2100. Taken with the longer-term effects from melting ice sheets in Greenland and Antarctica, that means any strategy to endure sea-level rise must involve adaptation plans as well as efforts to slow the trend.

在2019年9月的报告中，IPCC提高了对本世纪末海平面的最高预测，警告称2100年前海平面可能上升1.1米(3.6英尺)。一些预测甚至更高——例如，2016年的一项研究表明，如果温室气体排放不迅速减少，到本世纪末全球海平面可能会上升0.5至1.3米(1.6至4.3英尺)。即使2015年的《巴黎协定》确实刺激了雄心勃勃的气候政策，到2100年，海平面预计仍将上升20至60厘米(7.8至23.6英寸)。考虑到格陵兰岛和南极洲冰盖融化的长期影响，这意味着任何忍受海平面上升的战略都必须包括适应计划以及减缓这一趋势的努力。

5.Up to 216 million people currently live on land that will be below sea level or regular flood levels by 2100.

到2100年，将有多达2.16亿人生活在低于海平面或正常洪水水位的土地上。

Higher sea levels can exacerbate storm surges, like this 2013 flood in Wenzhou, China. (Photo: STR/AFP/Getty Images)

The situation is also urgent for low-lying island nations like Kiribati, the Maldives, the Marshall Islands and the Solomon Islands, where land is already so close to sea level that a few inches make a world of difference. Some are even mulling mass relocations — the government of Kiribati, for one, has a web page outlining its strategy for "migration with dignity." A town on Taro Island, the capital of Choiseul Province in the Solomon Islands, is also planning to move its entire population in response to rising seas. The small community of Newtok, Alaska, has already begun the difficult process of transplanting itself away from the encroaching coast.

对于基里巴斯、马尔代夫、马绍尔群岛和所罗门群岛等地势较低的岛国来说，情况也很紧迫。这些国家的陆地已经非常接近海平面，只要几英寸高，就会造成天壤之别。有些人甚至在考虑大规模搬迁——比如基里巴斯的政府，就有一个网页概述了它的“有尊严的移民”战略。所罗门群岛乔瑟尔省首府塔罗岛上的一个小镇也计划迁移全部人口，以应对海平面上升。阿拉斯加纽托克的一个小社区已经开始了将自己从不断侵蚀的海岸移植出去的艰难过程。