In traditional Chinese philosophy rain is always seen as a blessing. Thanks to the tail end of Hurricane Chris, the last hose-pipe ban was lifted yesterday , I expect that we won’t need to worry about bans for a while now, but scenes of dejected farmers with rotting potatoes and people clearing out ruined household furniture are the less pleasant side of the coin. Apparently, during the drought in south east England people responded very well to the need for water conservation, using low-flow shower heads and installing water butts to their gutter systems.
Recently parts of the UK and other countries, such as Thailand and Russia have experienced flooding that demonstrates water’s potential to powerfully interrupt our day-to-day lives and sadly, in the worst cases of flash flooding, terminate them. In good measure, water is fundamentally important to us and it is only in either excess, dearth or impurity that it threatens our security and well-being.
Water? I admit to loving the stuff. I love the sound of the word and I love what’s in it. As a child I was forever falling into it for a closer look at a Stickleback or Ram’s horn snail. My parents resigned themselves to the fact that they couldn’t take me anywhere near a body of water without me riding home in disgrace, shivering, wrapped in a travel blanket. For some years my Wellington boot was visible sticking out of the quick-sand at Arnside, where I had parted company with it on a fool-hardy foray into the Kent Estuary. Somewhere beyond it lie the remains of a Lancaster bomber that crash-landed in WWII.
I think we all have our own special relationships with water, and vivid memories of our own interactions with it. Aesthetically there are few things that are more attractive than water in its various forms, provided that it is unpolluted and not threatening. Snowflakes represent perhaps, the quintessential perfect form, each one unique in its transient, intricate beauty. Bodies of water when still, mirror their surroundings and epitomise calm and tranquility, when in motion they can stir deep-seated passions within us that are beyond normal powers of expression. Clouds or mist do much to evoke mood in a landscape image, and in film the visual qualities can be accentuated by sound too. In personal proximity we also have the range of water scents to stimulate us. Instinctive attraction will no doubt play its part in its appeal but our water world is undeniably, incredibly beautiful and its denizens are fascinating. If you would like to view coarse fresh water fish, one of the best places to do so is The Rye in High Wycombe. It’s possible to view glimpses of Pike and Perch in clear, shallow water from the concrete sides of the pond there.
Here are some of Andy Luck’s images on the water theme, you can view more on wildopeneye.com
In practical terms there are few things that are more useful to life on Earth than water, and the more I learn about the substance, the more interesting and odd, it seems.
Here is some information about water that you might find interesting too:
What is water made of? A water molecule is generally thought to be made of two hydrogen atoms to every one oxygen atom (H2O), but in reality this idealised molecule only exists in computerised modeling and is described so for convenience, the water that we encounter is an eclectic mixture of molecules intricately bound together.
What is water like?
Well we all know this, surely, but I was surprised to find out how little I knew about it, and how little I still understand having read more about it. Water is such a common element of our lives that it tends to be the liquid by which we define all others, yet, as Martin Chaplin notes in his wonderfully comprehensive website Anomalous properties of water it is very far from typical. It behaves rather unlike anything else we know of in the cosmos. It is most dense at 4 degrees Celsius, above and below this temperature it becomes less dense, which is why ice floats, yet it can remain liquid in a superheated and super cooled state. Without nucleation points to trigger the freezing process, under certain conditions water can be cooled down to – 149°C, it can be superheated to 330°C. Amongst other peculiarities hot water has been found to freeze quicker than cold water in some circumstances (The Mpemba effect) and to arc across in a gravity defying bridge from one glass to another under the influence of high voltage (Source) it is only very recently (2009) that researchers have produced a clear explanation for the structure of liquid water by blasting it with X-rays (Source). Much about water is still not fully understood.
Water’s properties are so ideal for biochemistry that it seems made for it, or is it just that our terrestrial life has evolved with such intimate connection with water? Either way, life without water is inconceivable. Chaplin says “It is clear that life on Earth depends on the unusual structure and anomalous nature of liquid water. Organisms consist mostly of liquid water, (human water content decreases slightly with age but is generally about 66%). This water performs many functions and it can never be considered simply as an inert diluent; it transports, lubricates, reacts, stabilizes, signals, structures and partitions. The living world should be thought of as an equal partnership between the biological molecules and water.”
Water is highly reactive with other substances and conducts electricity well, thus it is very useful in the metabolic processes of biochemistry and biophysics within the normal temperature range found on our planet. It can dissolve many other materials and carry them in solution. Water is essential for all biological processes to occur, it is the medium through which we breathe (dry lungs would be fatal). Its value as a heat store, as an oxygen carrier, the fact that it freezes from the top down and its high surface tension all aid aquatic life.
In extreme water scarcity, the only way life can survive at all is to encyst. Remarkably, lungfish and certain frogs have adapted to survival in suspended animation for long periods without water. African Lungfish can survive encased in mucus, buried in mud for up to 3 years.
Water in motion whether liquid or solid as glaciers can transport huge volumes of undissolved material, too. Water is terraforming our world today and has been for billions of years. How many billions, you might wonder?
How old is terrestrial water? Water on Earth is thought to be about 4.3 billion years old. According to Science Daily, scientists from UCLA and Curtin University of Technology in Perth, Australia examined some rock from Western Australia using UCLA’s Ion Microprobe and found ancient zircon crystals that they believe had melted from a rock that had interacted with cold water at the Earth’s surface. They believe that there were cool oceans within 200 million years of Earth’s formation (Source). Oceans are thought to have formed about 8 million years after our planet did (Source). Much of our water is thought to have been brought to Earth in comet ice. Comets are believed by some scientists to have also brought the essential amino acid building blocks of life to Earth.
How much water is there on Earth?
That’s a tricky question because our hydrosphere isn’t confined to the Earth’s surface, but extends from the deepest caves up to the highest ice crystals in our upper atmosphere and for the most part isn’t static, but is on the move. The US Geological Survey has a good treatment of the subject on their dedicated web page (Source USGS). It’s worth viewing their webpage for all the details, in short they say that if all water in our ecosystem was collected into a ball it would measure 860 miles (about 1,385 kilometers) across, and its volume would be approximately 332.5 million cubic miles (mi3), or 1,386 million cubic kilometers (km3). A cubic mile of water equals more than 1.1 trillion gallons. So it follows that there are more than 365.75 trillion gallons of water in our ecosystem. I can’t imagine that sort of quantity, but thankfully a short documentary film in The Earth Explorer series, produced by Andy Luck represents this very nicely.
You can watch the whole of this short film on the Wildopeneye.com films page.
Thankfully water loss from our planet appears to be very slow. The USGS say that over 96% of our surface water is in the world’s oceans and there’s over 2,000,000 mi3 of fresh water under ground, but the vast bulk of fresh water 7,000,000 mi3 is contained in glaciers and ice caps.
How has the quantity changed over time? First there was no liquid water on Earth because conditions were simply far too hot. After the “Late Heavy Bombardment” of Earth by asteroids and comets, about 3.8 billion years ago there was considerably more water than exists today. Scientists from The University of Copenhagen and Stanford University have studied ancient rocks from Greenland to reconstruct the isotopic composition of 3.8 billion years old seawater in efforts to establish Planet Earth’s allocation of water, our “water budget”. They discovered that Earth has lost less than a quarter of its water budget since those zircons formed. There used to be about 25% more water on Earth than there is today. They were surprised that more water hadn’t been lost (Source).
Our water is constantly being recycled in a process called the water cycle, there is a very nice illustration of the water cycle on the USGS site (Source).
The next post in our series will touch upon human use of water.