Science - Water water everywhere, and not a drop to drink - Liam Gavin
Earth is a very watery planet. About 71% of the Earth’s surface is covered by water, and the oceans hold about 96.5 % of all water. The bottom 1,000 metres of the Earth’s atmosphere alone contains about 1,000,000,000,000,000 litres of water and in total, there is around 1,260,000,000,000,000,000,000 litres of water on the planet. Life on Earth could not have happened were it not for the fact that a few lucky co-incidences meant that we had all this water around us. First, we were not too close to the Sun, which would have caused all the water to evaporate. Second, gravity was strong enough to keep it from floating off into space, and third, shortly after the Earth was formed, we were bombarded by lots of tiny watery planets, comets, and what was basically lumpy rain from space, and it all settled on the surface, and made our oceans, rivers, lakes and us.
And yet, with all this water around, we still manage to run out of the stuff whenever we get a few weeks of dry weather. This, of course, is because our water is
not evenly distributed around the planet. Some places get more than their fair share.
Mawsynram, in India, wins the prize for the wettest place in the world, with annual rainfall of nearly 12,000 mm, while in parts of Chile’s Atacama desert, rainfall has never been recorded at all. For decades, we have been trying to figure out a way of releasing the water vapour trapped in the air, and making it rain in areas that are suffering from long- term water shortages. From ritualised rain dances, at one end of the scale, to cloud seeding by airplanes at the other, none of the methods have had widespread success.
The Whisson Windmill But in 2007, a retired medical doctor turned inventor called Max Whisson, claimed to have invented a type of wind turbine that powers a refrigeration unit, to extract the water from the air in much the same was as a cold can straight out of the fridge ends up covered in
condensation. He claimed that a small rooftop mounted device could produce 7,000 litres a day, even in a light breeze. All he needed was funding. Ah, there’s the problem. Unfortunately his idea proved too good to be true. There is a very comprehensive review of the maths showing how he miscalculated the results at: https://www.skepticforum.com/viewtopic.php?t=7930 it is more likely that the rooftop water generator would produce 7 litres a day rather than 7,000. Even so, that could be significant in parts of the world that get a lot less rain than Ireland. But Max Whissom never got to see his product hit the market, as he died earlier aged 93 this year in Autralia, with his Whisson Windmill so forgotten that it doesn’t even merit a mention on Wikipedia. Whisson is actually better remembered for his first invention, a single use hypodermic needle used in the treatment of aids. Calculations out by a factor of 1,000 But the bottom line is that although the theory is fine,
About 60% of the human body is water, and a newborn baby is actually 80% water.
Water recycles for billions of years Water is a combination of Hydrogen, which is the most commonly found element in the universe, and oxygen. All, or at the very least, a very large percentage of our water came from space, and the water that comes out of your tap is actually older than the Earth itself. All of the water that falls as rain has gone through a multi-billion year sequence of spending some time in the ocean, evaporating and forming clouds, falling as rain on the sea or on land, where some soaks into the ground, and some ends up in plants, or in rivers, where it might just flow back to the sea, or it could find it’s way into your kettle. It is statistically likely that some of the water you drink today was once drunk by Jesus, or Caesar, or one of the great Greek philosophers.
25
Made with FlippingBook - Online magazine maker