Skip to main content

There is no such thing as a water shortage

Well, it has been sunny here for several days in a row now, so any time soon we can expect a hosepipe ban.

The idea of a water shortage is crazy when you think about it. Looked at from space, the defining feature of the Earth, when compared with the other planets in our solar system, is water. Our world is blue with the stuff. In round figures there are 1.4 billion cubic kilometres of water on the Earth. This is such a huge amount, it’s difficult to get your head around. A single cubic kilometre (think of it, a cube of water, each side a kilometre long) is 1,000,000,000,000 litres of water.

Divide the amount of water in the world by the number of people and we end up with 0.2 cubic kilometres of water each. More precisely, 212,100,000,000 litres for everyone. If you stack that up in litre containers, the pile would be around 10 million kilometres high. With a reasonable consumption of 5 litres per person per day, the water in the world there shouldn't be a shortage for 116,219,178 years. And that assumes that we totally use up the water. In practice, the water we ‘consume’ soon becomes available again for future use. (If it didn't we'd all blow up like balloons and pop.) So where’s the water shortage?

Things are, of course more complicated than this simplified picture suggests. In practice, we don’t just get through our five litres a day. The typical Western consumer uses between 5,000 and 10,000 litres. In part this happens directly. Some is used in taking a bath, watering the lawn, flushing the toilet – but by far the biggest part of our consumption, vastly outweighing personal use, is the water taken up by manufacturing the goods and food that we consume. Just producing the meat for one hamburger can use 3,000 litres, while amazingly a 1kg jar of coffee will eat up 20,000 litres in its production.

However, even at 10,000 litres a day, we still should have enough to last us over 57,000 years without even reusing any water. So where is the crisis coming from? Although there is plenty of water, most of it is not so easy to access. Some is locked up in ice or underground, but by far the greatest majority – around 97% of the water on the planet – is in the oceans. It’s not particularly difficult to get to, certainly for any country with a coastline, but it is costly to make use of. The fact that an island nation like Britain is prepared to spend huge amounts of money on reservoirs to collect a relatively tiny proportion of fresh water, rather than use the vast quantities of sea that surrounds it, emphasizes just how expensive is the desalination required to turn seawater into drinkable fresh water.

Water shortages, then, come down to a lack of cheap power. There isn't a water shortage, there's a power shortage. Getting more, cheaper, cleaner energy should be a much bigger priority than it seems to be - as so many of the problems the worlds faces are really energy problems in disguise.

Image from Wikipedia

Comments

  1. Perfect solution for obesity workshop india, overweight workshop india

    & fitness solutions india

    Perfect solution

    ReplyDelete

Post a Comment

Popular posts from this blog

Why I hate opera

If I'm honest, the title of this post is an exaggeration to make a point. I don't really hate opera. There are a couple of operas - notably Monteverdi's Incoranazione di Poppea and Purcell's Dido & Aeneas - that I quite like. But what I do find truly sickening is the reverence with which opera is treated, as if it were some particularly great art form. Nowhere was this more obvious than in ITV's 2010 gut-wrenchingly awful series Pop Star to Opera Star , where the likes of Alan Tichmarsh treated the real opera singers as if they were fragile pieces on Antiques Roadshow, and the music as if it were a gift of the gods. In my opinion - and I know not everyone agrees - opera is: Mediocre music Melodramatic plots Amateurishly hammy acting A forced and unpleasant singing style Ridiculously over-supported by public funds I won't even bother to go into any detail on the plots and the acting - this is just self-evident. But the other aspects need some exp...

Murder by Candlelight - Ed. Cecily Gayford ***

Nothing seems to suit Christmas reading better than either ghost stories or Christmas-set novels. For some this means a fluffy romance in the snow, but for those of us with darker preferences, it's hard to beat a good Christmas murder. An annual event for me over the last few years has been getting the excellent series of classic murderous Christmas short stories pulled together by Cecily Gayford, starting with the 2016 Murder under the Christmas Tree . This featured seasonal output from the likes of Margery Allingham, Arthur Conan Doyle, Ellis Peters and Dorothy L. Sayers, laced with a few more modern authors such as Ian Rankin and Val McDermid, in some shiny Christmassy twisty tales. I actually thought while purchasing this year's addition 'Surely she is going to run out of classic stories soon' - and sadly, to a degree, Gayford has. The first half of Murder by Candlelight is up to the usual standard with some good seasonal tales from the likes of Catherine Aird, Car...

Is 5x3 the same as 3x5?

The Internet has gone mildly bonkers over a child in America who was marked down in a test because when asked to work out 5x3 by repeated addition he/she used 5+5+5 instead of 3+3+3+3+3. Those who support the teacher say that 5x3 means 'five lots of 3' where the complainants say that 'times' is commutative (reversible) so the distinction is meaningless as 5x3 and 3x5 are indistinguishable. It's certainly true that not all mathematical operations are commutative. I think we are all comfortable that 5-3 is not the same as 3-5.  However. This not true of multiplication (of numbers). And so if there is to be any distinction, it has to be in the use of English to interpret the 'x' sign. Unfortunately, even here there is no logical way of coming up with a definitive answer. I suspect most primary school teachers would expands 'times' as 'lots of' as mentioned above. So we get 5 x 3 as '5 lots of 3'. Unfortunately that only wor...