Watery musings on a finite resource
Head of Sustainability, Dr Dylan Bright, considers the wonders of water
A few Sundays ago after swimming, as we ate a sandwich in the cafe overlooking the pool, I became embroiled in another of a series of profound philosophical debates with my son (Oscar aged 8.25).Swimming on a Sunday always seems to stimulate these musings over a sandwich. He asked me why people like swimming and what is so important about water anyway; it had suddenly struck him as peculiar that we had so much to do with water.
Eight years ago as a new father I had resolved never to give him a patronising or knowingly inaccurate answer. I have, and will, I'm sure, continue to regret this resolution. What follows is a summary of the discussions and the evidence offered relating to the human interest in and reliance on water. I share them because, all too often, we forget to question the seemingly obvious.
Neil Armstrong said after viewing Earth from the moon, "It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small."
But did you know that 97% of that 'blue' seen by Neil Armstrong is salt water, the 3% remaining is fresh water and two thirds of that is locked up in the ice caps? And of that final 1%, the majority (99%) is not visible as it is groundwater. So of the freshwater in the world 0.01% is available to us and we need to share it with nature!
Why is water so crucial? Well let's start at the very beginning. Water is a strange molecule; it comprises one oxygen atom and two hydrogen protons. This should be a nice straight stable and electrically neutral molecule but for quantum reasons it's bent. The bend in the molecule means it has a bit of negative charge on one side and a bit of positive charge on the other.
This means the molecules electrically stick together giving us phenomena like capillary action, surface tension and the meniscus we all remember from the measuring cylinder in chemistry (do you measure from the top or the bottom of the meniscus!). The di-electric properties of liquid water also make it a weak universal solvent, more things dissolve in water than in any other liquid... so what? This property means that water is the only substance in which DNA can form and reform.
Where there is water there is life; from literally the molecular level, this truth persists right on up through or to our complex ecological and societal situation today. The earth is a closed system, similar to a terrarium, meaning that it rarely loses or gains extra matter. The same water that existed on the earth millions of years ago is still present today: water circulates endlessly. So it's entirely possible that the clean, treated water in which you take your next bath or shower also bathed Cleopatra or provided a drink for a Tyrannosaurus Rex.
Are we good custodians of this precious, finite, irreplaceable resource during our brief stay? Was Oscar satisfied with this compilation of evidence? Find out in my next blog....