I'm reading a book by Phillip Ball, called: Water, Matrix of Life. If you want to know more about water, it's fascinating and well written. I particularly like this quote of his: “Water is the agent of geological, environmental and global change. It confers fecundity on parched regions, while it's passing turns grasslands into deserts.”
Water does all this and more. But water is incredibly effective at what it does because water is a team player. Apparently there's water on the moon in the form of patches of ice, but it's inert, it doesn't do anything because it lacks the other team players. Let's introduce these other team members.
Water is a compound not an element although the Greeks and the Chinese thought it was one of the “four elements” - Earth, Air, Water and Fire. Let's run with this idea but let's assume that fire can mean all types of energy, especially the Sun. Let's use a bigger name for Air. We'll call it the Atmosphere. Let's say that “Earth” means the planet and not just a hunk of rock. Now let's add a fifth element, and call it “Life”.
Put these five elements together and they will interact spontaneously. And these interactions form the great geophysical systems of the Earth.
The Earth's surface has mountains and basins. It's lowest points are where most of the water is – in the oceans. The Earth's gravitational field is strong enough to hold all the gases: the oxygen, nitrogen, carbon dioxide, and water vapour that make up the atmosphere.
Think of Earth as a house without a switch because it runs itself. It's roof is the atmosphere. It lets vital energy from the Sun in and gives us a bit of insulation at night. Too much insulation is not good, as we see with the planet Venus, with its surface temperature of 460 *Celsius.
The Earth's got plumbing, heating, ventilation and power, mostly run by one system: the weather. But it's also got backup power from internal heat which causes plate tectonics to reconfigure the seas and continents every hundred million years or so.
It's not like a house that was designed and built, because it repairs itself. Tell me, what house that we have built repairs itself, or has lasted as long as Earth has?
As a plumbing and heating system and power system the weather is partly predictable and partly unpredictable. Sometimes we get too much water sometimes not enough. Sometimes it gets too hot, sometimes it's just right.
The weather operates under the usual physical laws. The Earth's spin causes winds to curve in the direction of rotation making cyclonic wind patterns counter-clockwise in the northern hemisphere and clockwise in the Southern Hemisphere.
The Sun's radiation heats water on Earth's surface and causes water molecules to change from liquid to gas. The water vapour can rise into the atmosphere because it contains heat from the sun.
Weather is partly predictable, we recognize the seasons, but also unpredictable, we don't know what the weather will be like a month from this day. The weather is a self-organizing system. Weather systems can last up to a week and travel thousands of kilometres.
Let's call a system: a group of parts that interact together to form a whole that is separated from the external world by a boundary.
Let's divide the world of systems into three: machines, institutions, and self-organizing systems.
Self organizing systems are systems of parts that interact via simple physical laws. The parts of the Solar system - the sun and the planets, interact by the laws of motion and gravity to form a balanced system that has maintained itself over time.
All machines are mechanical systems designed and built by humans for various goals. A house is a mechanical system that transfers heat and energy from outside and holds it inside. Houses and other machines have switches on them. When the switch is turned on, the machines start to work and when it's turned off they stop working.
What is a self-organizing system? Think of a flock of sandpipers flying low over the water – the precision and coherence of their flight. The flock swoops and glides as a unified whole as if it acts with one mind.
But each bird is acting on its own and the subtle alterations in flight that each bird makes in response to its neighbours creates an emergent unity.
Unlike machines, self-organizing systems are not deterministic. These systems have properties that emerge from the interaction of all the parts that cannot be predicted from the nature of the parts alone.
You cannot predict the weather beyond a week; Human behaviour is both predictable and unpredictable. Weather systems and large-scale human societies exhibit complex behaviour that is the hallmark of self-organizing systems.
I read Philip Ball's H2O in 2008, and found it an enjoyable book. Part of my new job in Leksvik was to design a science space for youth based on the themes of "Water,Energy & the Environment". My design consisted of changing a 150 m2 building into a 21st Century Nautilus. It never did get built in accord with the plans, as the building had to give way to an expansion of the school. We did, however, build ROVs as described in Harry Bohm's "Build Your Own Underwater Robots, and other wet projects." A ROV is very useful to explore the sea, even though ours never exceeded 5 meters depth. Today, I think I would just buy a ROV, rather than build it. The Trident is the most compelling ROV in the market: http://www.openrov.com/ The reason one wants to explore the marine environment with a ROV is not just to capture life on film, but also to measure parametere (such as temperature and acidity) on a regular basis. This is where data loggers (including home made Arduino units) can be very useful.
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