Water may be the most abundant molecule on the surface of the Earth, but more than 99% of it is frozen, underground, or too salty to drink. Only .007% of the planet's water runs in rivers and lakes, yet this precious amount sustains massive populations worldwide. Agricultural societies have long gone to war over water, and as the Earth's population balloons toward 10 billion, global warming destabilizes weather patterns, and pollution sullies what little is left to count on, the conflicts will only get worse. On Significant Figures, Peter Gleick traces Syria's civil war in part to "drought, agricultural failure, water shortages, and water mismanagement" in one of the driest regions in the world. In another post, Gleick considers Egypt's decades-old threat to fight for the waters of the Nile—which will soon be held up in Ethiopia, behind the largest hydroelectric dam in Africa. Gleick says "we need to stop assuming that our political stability is independent of what we do to our atmosphere or our water. It isn’t."