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.”
According to UN Water, “Each of us needs to drink 2 to 4 litres of water every day. But it takes 2000 to 5000 litres of water to produce one person’s daily food.” If that seems like a lot, it is. But it’s funny how much depends on your perspective. A graphic from the USGS shows what it would look like if all the water on Earth were gathered into one drop. On A Few Things Ill-Considered, Coby Beck discusses the even smaller drop that represents all fresh water. Coby writes, “A full 74.5% of that much smaller ball is locked away in ice caps and glaciers and 24.7% is groundwater (much of that out of reach). There is only .56% of the world’s freshwater circulating in lakes, rivers, rainfall, soil and the biosphere.” The sight of so little water against the rocky backdrop of Earth might inspire some to keep our water clean. But on Starts With a Bang, supervillain types dream of apocalypse. Ethan Siegel writes, “The ability to have liquid water is relatively rare: we need the proper temperatures and the proper pressures!” Without our 5.3 quadrillion ton atmosphere, there would be no water on the surface of the Earth, and without the magnetosphere generated by the planet’s core, we would have no atmosphere. Ethan continues, “Charged particles are bent by magnetic fields in very predictable ways […] if we could create a large enough magnetic field on Earth, we could poke a hole in the magnetosphere and allow the solar wind to strip our atmosphere away!”
On Friday, NASA scientists confirmed the discovery of water on the moon. Using spectral analysis to determine the composition of the plume resulting from last month’s LCROSS rocket collision, they found more than 100 liters of water. Steinn SigurÃ°sson on Dynamics of Cats calls the presence of water on the moon “amazing,” but cautions that at these concentrations, it’s “dry by Earth standards.” Razib Khan on Gene Expression considers the implications of water on the moon: “Since humans are mostly water by weight, this is very important when assessing the practical difficulties of colonization or settlement.” In other NASA news, Greg Laden reports on his blog that after idling on the precipice of a Martian dust bowl since April 23, while engineers on Earth assessed the best way to make a break for it, the long-lived Spirit rover will risk movement again tomorrow, in a bid to continue its incredibly successful mission.
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