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A new NASA map shows what parts of the country will likely soon suffer from extreme floods, major droughts, and other water-related calamities.
A billion people could lose easy access to water by the end of the century, triggering mass migrations, food shortages, and wars.
In Dhaka, severe shortages have forced residents to get resourceful.
Sana'a could literally run out of water by 2017. And so far, very little has been done