there are a few things that present day explorers should look for.

那裡有些現代探險家應該尋找的東西

First, as you travel along the Great Harbor,

首先，當你沿著大港旅行

keep your eyes open for large columns and statues.

記得睜大眼睛注意那些大列柱和雕像

Across the bay to your left is the island where the Great Lighthouse once stood.

穿過海灣，你的左邊是一個曾經有大燈塔佇立的海島

And as you make your way through the palaces of the Royal Quarter

然後當你走過皇宮

and reach the area where the Library of Alexandria once stood,

並到達曾經是亞力山大圖書館的區域

keep your eyes open for sharks.

張大眼睛注意鯊魚

Because if you visit this section of Alexandria,

因為當你參觀亞力山大帝國的這個地區

you'll be fifteen feet deep in the Mediterranean Sea.

你是在 15 尺深的地中海中

Though people are most familiar with Plato's fictional Atlantis,

儘管人們最熟悉的是柏拉圖編造的亞特蘭提斯

many real underwater cities actually exist.

其實許多水下城市是真的存在的

Places like Alexandria,

像是亞力山大港、

Port Royal, Jamaica,

牙買加的皇家港、

and Pavlopetri, Greece.

希臘的帕夫洛彼特里

Sunken cities are studied by scientists

科學家研究沉於水面下的城市

to help us understand the lives of our ancestors,

讓我們了解我們祖先的生活、

the dynamic nature of our planet,

我們星球上多變的自然環境

and the impact of each on the other.

以及對彼此的相互影響

Water is essential for life, food sources, and transport,

水對於生命、食物資源及交通是不可或缺的

so many cities have been built along coastlines and river banks.

所以許多城市都會沿著海岸線和河岸建造

However, these benefits also come with risks

但這些好處也潛藏危機

because natural forces that can sink a city are at their doorstep.

因為可以使城市淹沒的大自然力量近在咫尺

Take, for instance, an earthquake.

例如地震

June 7, 1692 seemed like a normal morning in Port Royal, Jamaica,

西元 1692 年 6 月 7 日，在世界上最富有的港口之一 —— 牙買加的皇家港

then one of the richest ports in the world,

看似跟往常一樣的早晨

but when a massive earthquake struck,

當一個超級大地震來襲

two-thirds of Port Royal immediately sank to its rooftops.

三分之二的皇家港便瞬間沉沒滅頂

Today, many buildings and elements of everyday life

今天，日常生活看到的建築和零件

remain surprisingly intact on the sea floor, frozen in time.

令人驚訝地，仍原封不動地保存在海底，時間彷彿凍結了

That includes a 300-year-old pocket watch that stopped at 11:43,

包括一只三百年前的掛錶，時間停留在 11:43

the moment Port Royal slipped beneath the Carribean.

也就是皇家港沉到加勒比海下的時刻

And during the winter of 373 BCE,

另外，在西元前 373 年的冬天

the Greek city of Helike was struck by an earthquake so strong

希臘的赫里克城受到強烈地震的侵襲

that it liquefied the sandy ground upon which the city was built.

使得城市建設下的土壤液化

Minutes later, a tsunami struck the city,

幾分鐘後，城市受到海嘯侵襲

and Helike and its inhabitants sunk downwards into the Mediterranean Sea.

赫里克城和其居民全都沉到了地中海

Centuries later, Roman tourists would sail on the lagoon that formed

過了好幾世紀，羅馬觀光客會在後來形成的潟湖航行

and peer down at the city's remains.

並且往湖裡看見城市的遺跡

Earthquakes are sudden, unpredictable disasters

地震是突然且無法預知

that have drowned cities in an instant.

並且可以使城市瞬間沉沒的災難

Luckily, however, throughout history,

然而幸運的是，縱觀歷史

the majority of sunken cities were not submerged by a single cataclysmic event,

大部分被淹沒的城市並不是因為單一劇烈變動的事件造成的

but by a combination of more gradual processes.

而是一連串漸進的過程

For instance, Pavlopetri, the oldest known sunken city,

例如，已知最古老的海底城鎮，帕夫洛彼特里城

was built on the southern coastline of Greece 5,000 years ago.

在 5000 年前建在希臘的南方海岸線上

It's an example of a city that was submerged due to what is called isostatic sea level change.

這個城市是因所謂地殼均衡的板塊運動而淹沒的一個例子

18,000 years ago when the Ice Age ended,

一萬 8000 年前冰河時期結束

glaciers began melting and the sea level rose globally until about 5,000 years ago.

冰何開始融化，全球海平面持續上升，直到大約 5,000 年前才緩和

Isostatic sea level change isn't caused by that melt water,

地殼均衡的板塊運動並不是融化的水造成的

but rather the Earth's crust slowly springing back from the released weight of the glaciers,

而是因為地球的板塊隨著冰河重量的釋出而彈起

making some places rise, and others sink.

使得有些區域上升，有些則下沉

The ground around Pavlopetri is still sinking at an average rate of a millimeter per year.

帕夫洛彼特里城周圍的土地至今仍在以每年平均一毫米的速度下沉中

But the ancient inhabitants were able to move gradually inland over several generations

而古代的居民幾個世代以來，得以移往內陸

before they finally abandoned the city about 3,000 years ago.

直到 3,000 年前，他們終於離開這座城

Today, divers swim over the streets of Pavlopetri

今天，潛水者游過帕夫洛彼特里城的街道

and peer through ancient door jambs into the foundations of houses and community buildings.

並且透過老舊的門側柱可以看見房子的地基和社區建築

They learn about the people who lived there by observing what they left behind.

透過觀察人們留下的東西，可以了解當時當地居民的生活

Natural geological events, such as earthquakes and tsunamis,

像是地震及海嘯這類的自然地理現象

will continue to shape our continents,

將會持續影響我們所居住的大陸

just as they have for millions of years.

如同這幾百萬年來一樣

As increased global warming melts our polar ice caps at accelerated rates

當加劇的地球暖化造成極地冰帽快速融化

and sea levels rise,

以及海平面上升

we will be forced to adapt,

我們將被迫適應這個環境

like Pavlopetri's inhabitants.

就像帕夫洛彼特里城的居民一樣

Undoubtedly, over the coming centuries,

接下來的幾個世紀，毫無疑問地

some of the coastal areas that we live in today

我們現今所住的海岸地區

will eventually be claimed by the water, too -

也終將被海水淹沒

cities like Venice,

像是威尼斯、

New Orleans,

紐奧良、

Amsterdam,

阿姆斯特丹、

Miami,

邁阿密、

and Tokyo.

以及東京

Imagine what future civilizations will learn about us

想像未來的文明會怎麼認識我們

as they swim around the ancient ruins of the cities that we live in today.

尤其是當他們游在我們今天居住的城市廢墟周圍的那一天