Equilibrium pursuits of natural processes are subtle most of the time. The subtlety lets us feel that everything is guaranteed that nature has to offer. But when nature’s actions become disruptive and destructive we look at nature in awe and realize the enormity of its power. Nature’s forces – the powers of earthquakes, volcanoes, tsunamis, floods, landslides, hurricanes, and storm surges are no match to our limited power – in our scale of thinking and doing things.
Some of these forces are so powerful and so extensive that they make us feel small and helpless – we start saying one cannot argue with Mother Nature. Structures and monoliths however strong they may appear, are destabilized and crumbled like toys, essentially flowing like fluid. The destructive power of nature tells us to know our limits and work responsibly within it – that nature needs room to stretch and wake up now and then to relieve some of its stresses.
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Our memories are still fresh with the devastation of the 2005 Hurricane Katrina, the 2004 and 2011 tsunamis in Indonesia and Japan (Japan tsunami image, credit: anon). Now we have better ideas of how these types of forces are caused, but in ancient times the events have inspired people to think of them as actions of super-natural beings.
Scientists tell us that apart from their disruptive sides, these types of violent actions have been responsible for the development of atmosphere, and the birth and evolution of bio-chemical lives – plants and animals. The continuity of life is ensured with plants absorbing Earth’s nutrients like sponges, and animals developing webs of eating habits in the myriad layout of food chain.
Perhaps this means all that happens has a purpose; nothing is lost in the wide canvas of life and existence. Does this imply that nature’s violent actions are to be mimicked by humans? The answer is definitely no. The reason is that the human scale of things – life cycle and tolerance thresholds is much smaller than nature’s. Therefore for humans, small is beautiful and sustainable. The sustainability and beauty can be explained and interpreted from all different perspectives in order to achieve reasonable goals. But one thing is sure and it is the fact that our prosperity should not be considered as something dependent on upsetting nature to cause irreparable damage – rather working with it within limits. It is not a wise policy to create cases of human-made potential disasters to add on top of natural disasters.
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How are nature’s actions required to turn the wheel of equilibrium conceived in a workable form? Let us try to revisit the concepts and definitions we know.
In simple considerations, all physical actions are described in terms of four inter-related parameters - energy, force, work and power. Energy is the ability to do something. We all have different physical energy depending on our health, body structure, strength and acquired skill level. Similar can be said about our mental energy which again depends on on mental health, education, caliber and experience. When given to work, we all perform differently depending on this potential energy.
Force is the measure of applied energy to do work in a certain direction for a unit measure of change in position. Work is the total accomplishment of the applied force and is equivalent to the applied energy. Power is the work done in unit lapse of time. Also fundamental to the concept is the mass, which according to Einstein’s (1879 – 1955) famous Theory of Relativity is equivalent to stored energy. We will have more occasions to explore the extraordinary brilliance of Einstein – one of the greatest minds in the history of mankind.
Perhaps a practical example would illustrate the meaning of these parameters better. A pole-vault thrower applies his body strength and skill level to throw a pole. The impact the pole has on the ground is the measure of force – and is the product of the mass of the pole and its rate of change of velocity. The average force multiplied by the distance traveled by the pole is the measure of the applied energy or work done. The power of the athlete is measured by the time taken by him. The faster the pole strikes the ground the more powerful is the energy applied by the athlete.
Now while the pole races throw air, some of the applied energy is lost through friction. The lost energy is proportional to the density and viscosity of the medium, and the force applied on the pole. For example, if the same pole is thrown in water with the same force, more energy will be lost, because water is more dense and viscous than air. According to conservation principle, energy or equivalent mass-energy can neither be created nor destroyed implying that the lost energy must transform into heat and sound.
Physicists see all natural forces as four fundamental types – the gravitational force, electromagnetic force, strong nuclear force and weak nuclear force. Einstein’s theory of mass-energy equivalence in its most demonstrated form represents the strong nuclear force – where an atom is split to transform its mass into energy. Weak natural force is the radiation of radio-active materials. Most of the natural actions are forced by Newtonian gravitational force, or in macro-scale thinking, by Einstein’s accelerating force in the space-time curvature of the mass-energy field.
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Propagating energy distorts the medium to a wave form – like we see in ocean waves. Most energy propagates through a medium, except electromagnetic and gravitational radiations which do not require a describable medium to propagate energy. It seems the requirement of a medium becomes redundant as energies propagate at the very high speed of light – 671 million miles per hour. The product of energy and its speed of propagation is known as energy flux – that we have talked about on earlier occasions.
In addition to the equilibrium quests of natural processes, there are many connotations of propagating energy in life and social interactions. But, for now let us think about two important aspects in the context of human interventions on natural processes. Firstly, are human ambitions driving all to take unmanageable risks to create interventions in catastrophic proportions? Secondly, is it at all possible to protect ourselves from extreme catastrophic events?
We have answered the first question somewhat earlier. We all know that the more we become confident of ourselves, the more we tend to become ambitious to build larger and larger thus entering into the unpredictable or poorly understood areas of risks. The risks that we take are like creating a time capsule that is destined to bust – if not now, may be sometime in the future. Safeguards and precautions that we think adequate now, may prove to be blindsided by ambitions and arrogance in later times.
Fortunately, the growing awareness of the problems in recent times is helping all to appreciate the necessity of steering the wheel in the right direction by working on the development of smarter methods and sophisticated risk management tools. No seemingly smart method is full-proof however.
The relevancy of the second question knocks our door each time we think about the devastation of natural disasters. While facilities destroyed by the Indonesia tsunami could be understood because there were hardly any existing infrastructure for protection against extreme events of such magnitudes. The same cannot be inferred about protection facilities destroyed by Hurricane Katrina storm-surge flooding in USA, and the Japan tsunami. The facilities in these two developed countries were supposedly adequate or assumed to be somewhat sufficient to protect lives and properties.
Therefore one may argue that there might be a gap in our understanding and characterization of some extreme events. One likely flaw is that we treat an extreme event as an extrapolation of some other lesser events assuming that all of them have comparable characteristics. Unfortunately, this assumption has the risk of overlooking high randomness and non-linearity of extreme events, and their loadings on and reactions from structures we build.
Let me reinforce this by highlighting a warning from the US Army Corps of Engineers as described in the Coastal Engineering Manual. It answers the second question partly referring to our misconception of rare weather events or combination thereof: “It is important to bear in mind that the most extreme record of event may not merely be an intensified version of lesser extreme events. . . Often the catastrophic event arises from an unusual interaction between several major weather features. The Halloween Storm that occurred in the northwestern Atlantic Ocean in October 1991 is a good example. Three significant meteorological systems, including a hurricane and an intense winter storm, combined to create very strong winds over an extremely long fetch, which lasted for a period of days. This type of event is difficult to anticipate, but it should be recognized that such things can occur. They may appear as outliers in extreme data distributions.”
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In a lighter vein let us take a glance at Murphy’s Law, anything that can go wrong, does go wrong. Is it certainty or uncertainty?
In my next posting I will be talking about the Fluidity of Nature.
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Here is an anecdote to ponder:
The disciple asked the master, “Sir, I wish to defy gravity and levitate to float in air.”
The master thought for a while and laughed loud, “Good, my dear! Try to slow down and decelerate.”
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- by Dr. Dilip K. Barua, 12 May 2016