Title: H2O – A Biography of Water
Author: Philip Ball
Publisher: Phoenix, U.K 2004 (First published: 1999)
ISBN: 0-75381-092-1
Pages: 346
Water has been the foundation on which life on earth placed its cornerstones. Without water, most of the flora and fauna would disappear in a matter of weeks. Yet, we have taken water for granted for most of our lives and pay scant regard for its preservation, waste minimisation and effective utilization. Philip Ball, an editor at Nature, the reputed science journal and a freelance writer has brought this volume with a profound insight into the several ‘W’s of water – when, where, what, why and whither. A lot of branches of science are covered in this book, including astronomy, geology, chemistry, physics, biology, environmental science and some politics is also sprinkled in. Water, in its every manifestation has found coverage in an admirable way, which makes compelling reading. The book is a delight to read from cover to cover.
The book begins with a splendid review of how water was formed. Examines the constituents, hydrogen and oxygen and explains how these gases formed first in the universe. Big bang and stellar evolution is explained and we see that these elements first formed in the thermonuclear cauldrons which were the star generators. The earth, which formed 4.6 billion years ago might have filled with water (mostly in vapour form as the earth was very hot then) by the constant bombardment of comets which carry ice. About 4 to 4.4 billion years ago, the earth cooled and the water vapour rained down on earth, forming oceans and inland lakes. Water was also steadily losing from the atmosphere at that time, by the process of photolysis at the upper atmosphere. Sun’s ultraviolet rays break water into its constituent gases, hydrogen and oxygen, of which the former peters out to space due to it is so light. Water is lost every year in this way, at the rate of a small lake.
Water controls the planetary climate, with a very large influence exerted by the ocean currents, both warm and old. There is a great amount of water flowing through these currents known as the ‘Great Conveyor Belt’, linking Atlantic, Indian and Pacific oceans. This current carries warm tropical waters to north Atlantic which explains why Northern Europe is comparatively warm as compared to the arctic climate in North Canada which lies also at the same latitude. Any deviation in the normal running of this conveyor belt would greatly affect the world climate. As earth was moving away from the last ice-age 12,000 years ago, there was a sudden breakdown of the conveyor belt, causing ice-age like cooling around 10,500 years ago, known as the Younger Dryas Event. This was caused by the mixing of glacier melt water with the warm salty water of the conveyor, diluting it and making it float, instead of sinking, which is required for the conveyor to work. Human induced global warming, may do just that again. Water exists on earth in atmosphere, surface and underground and its destructive power is evident from floods, hurricanes and tsunamis.
Water, locked up in glaciers constitute 75% of the fresh water reserves. Glaciers have been receding over the last two centuries due to warming of the atmosphere. Effects on the ice sheets in Greenland and Antarctica are not significant even now, but the situation may change if pollution is not reined in. Ocean levels have risen by 2 to 6 cm in the last century and it is high time humanity shoud sit up and take note. We should hope for the best, but prepare for the worst.
Water is present in most of the rocky planets and satellites in the solar system. Traces of water is confirmed on the moon and mars. Wild ideas to populate mars involves the melting of polar ice on that planet by concentrating solar rays or introducing CFCs to induce warming in the thin martian atmosphere. Water is however, much more abundant in the satellites of large planets like Jupiter and Saturn, particularly Europa, which is said to possess an ocean of liquid water beneath its surface. Water has been observed to reside even in the sun’s cooler parts of the photosphere.
Water was considered to be one of the four elements from Greek times (the others being earth, fire and air). The chemical discovery of water, of identifying its components was done in the 18th century. By 1775, Oxygene (acid former) and Hydrogene (water former) were described by Lavoisier in France. Chemical reactions between these two gases to form water was first observed by Henry Cavendish in 1781. The chemical formula was suggested by Swedish chemist, Jons Jakob Berzelius and H2O was formally born!
Water is a strange liquid, which is not at all an understatement. When all liquids become denser when they solidify, water does the reverse, which is why the solidified top surface of water bodies – lakes, rivers – floats above the liquid below. It has high boiling and melting points as compared to other tetrahedral compounds like methane and hydrogen sulphide. Water has a tetrahedral structure, having two hydrogen atoms and two lone pairs of electrons of oxygen atom at the ends of the tetrahedron make hydrogen bonds with neighbouring molecules, requiring more energy to break the bonds when a state-change occurs. The structure of water was described by Linus Pauling about 60 years ago.
If water is a strange liquid, ice is not far behind as it is a strange solid too. It forms 12 different forms under very high pressure. Of these, a form known as Ice-VII remains solid even at 100 deg C, though at an astronomically high pressure of 22,000 atmospheres. The structure of these unusual crystals were understood and widely studied only in the 1980s. Water turning to ice is a challenge to life forms and they have adapted themselves to live in extreme cold by evolving anti-freeze proteins in the blood stream and developing freeze tolerance.
Early life forms on earth produced glucose from carbon, hydrogen and oxygen, with hydrogen taken from hydrogen sulphide, which was abundant then. When water became plentiful, cyanobacteria evolved to extract hydrogen from water and the remaining oxygen was released to the atmosphere. This might have been the mechanism by which oxygen levels soared to the present-day quantities. This surge in oxygen helped aerobic respirators, which were the precursors to animal life to evolve by burning sugars to carbon dioxide and water with heat release as byproduct. Photosynthesis by plants helped the earlier animate life to gather food on land and the migration to and colonization of dry land began. It has always been a perplexing effort to describe how trees lift water from the ground to its top canopy. A conventional pump can lift water only by 10 metres whereas redwood trees take them as high as 100 metres. This is caused by the extremely narrow capillaries inside the trunk, the top side of which is open causing some water to evaporate at the top. This causes a negative pressure and water is pulled from the bottom. Water at such low pressures may be said to be in a superheated state which would immediately change to vapour if released.
Not only the outside, but the cell interior is also controlled by water. Most of cytoplasm is water and it may be thought that when life migrated from sea to dry land, it brought the sea with them. Water exercises critical control of the microbiological processes inside the cell. Ensuring proper way in which proteins fold is a life-critical process mediated by water. Protein folding occurs when hydrophobic areas of the protein are protected from water by hydrophilic areas by folding and covering them. The shape is very crucial for the proper function of the protein. Hydrogen bonds of hydrophilic parts among themselves and surrounding water determines the shape.
Science is an ongoing process in search of knowledge and sometimes, false starts and forgeries are reported even in reputed science magazines. Three such cases involving various aspects of water, such as polywater, cold fusion and infinite dilution are discussed in detail, though one wonders whether such pranks deserve the elaborate coverage meted out to them.
The book ends with dire warnings to protect, conserve and sustain water resources. Tomorrow’s world may be riddled with water wars as each nation strive to control the precious resource which becoming scarcer by the day. One aspect of the Arab-Israeli conflict in the middle-east is the water in river Jordan.
Many interesting facts and observations are given in the book one of which gives an answer to why the sea shore smells the particular way it is. Certain phytoplanktons in the sea produce a gas called dimethylsulphide (DMS) as a byproduct of their metabolism. The distinctive odour of DMS is responsible for the invigourating smell of coastal sea. It also gives a nice description of the logic in accepting a new and controversial scientific idea by science journals. As he says, “Let’s say that an acquaintance, someone we do not know well enough to trust implicitly, proffers to us the information that one can buy blue apples in Peru. We could choose to believe this at face value – but I submit that most of us would not. Why? Because it requires too much reorientation of facts we already feel to be secure. That blue apples might exist is not obviously an impossibility; but it stretches credulity to think that we would not have already known of so remarkable a thing, if it were true. Of course, we all have vast vistas of ignorance even of the most mundane of topics, but I suspect we feel rather secure in the notion that we have not been labouring all our lives under a fundamental misconception about the colours of apples. It is far more reasonable – though not necessarily correct – to assume that we being spun a yarn” (p.252).
An interesting sequel to this book may be ‘Four Elements’ by Rebecca Rupp which explores all the four elements, but not in such exacting detail as this book. That title was also reviewed in this blog earlier. (Read full review).
A splendid book which should be read by any science enthusiast. The author’s experience at Nature tells itself with the clear and logical elucidation of ideas. Some portions, particular ones dealing with the molecular structure of water and ice may seem a bit difficult, tempting the reader to gloss over them. Very few books provide such a treasure house of details covering so many branches of science in about 350 pages.
The book is highly recommended.
Rating: 4 Star
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