KARACHI, Nov. 19 -- One of the world's first cities came close to being wiped off the map during tragic floods this summer in Pakistan. Though Mohenjo Daro survived, it has become a symbol of the threat global warming poses to humanity's cultural heritage.

Built in around 3000 BC by the Indus civilisation in modern-day South Asia, Mohenjo Daro was not swept away by the floods, most likely thanks to the genius of its designers.

Perched high above the Indus river, the city was equipped with a primitive drainage system and sewers, meaning much of the floodwaters could be evacuated.

Nearly 1,600 Pakistanis died in the floods and 33 million others were affected in a disaster "probably" made worse by global warming, according to World Weathe...