Lucky Planet

Title: Lucky Planet – Why Earth is Exceptional and What that Means for Life in the Universe

Author: David Waltham

Publisher: Icon Books, 2014 (First)

ISBN: 9781848316560

Pages: 225

The earth’s atmosphere is slowly warming up by the increasing contribution of carbon dioxide in it. Scientists are justifiably worried by this global warming because of the uncertainties associated with its causes and mechanisms. The greenhouse effect which drives global warming is a very dangerous thing as we can witness on the Venusian surface. Its atmosphere is almost fully constituted by carbon dioxide (96%) and the associated warming has escalated the surface temperature to a blistering 460 degrees Celsius. Compare this to earth’s 15 degrees C. How come our planet turned out to be an ideal ‘cold spot’ for life? Analysing the earth’s past buried in rocks and ocean sediments bring out the picture of a habitable planet for most of its existence. This book examines the reason for this life-friendliness of earth. All parameters that control the weather are free to swing in any direction that can cause havoc, but we have been able to stave off disaster till now. This book investigates the idea that good fortune, or plain luck, infrequently repeated elsewhere in the universe, played a significant role in allowing the long-term habitability of earth and shows why it is unlikely to find similarly complex life elsewhere in the universe. David Waltham is a lecturer at the University of London, which he joined after a stint in the oil industry as a geologist. He is basically a physicist with an immense background in handling various aspects of geology.

Ancient societies gave our planet a prime position in their mythology and thought that other heavenly bodies revolve around it. Modern religion presumed it to be a special creation of God for the benefit of mankind. Primacy began to erode in the Renaissance period when thinkers postulated about the likelihood of numerous planets very similar to our earth in the new worlds they were observing with their newly made telescopes. Early thinkers attributed earth’s privileged position to divine providence, whereas the author puts it down to good fortune: a good fortune that is inevitable somewhere in a big enough universe. As scientific knowledge grew, earth became just a chance composition that occurs in a very, very rare moment. Waltham hints that it has become scientific heresy to question Giordano Bruno’s insight of the mediocrity of earth's position. He reproduces the story of Bruno which makes us believe that his execution was caused not by the beliefs, but by his bothersome proclivity to make enemies of everyone he came into contact with. This book then claims that we need to return to a geocentric cosmology in the sense that the earth may be the most interesting place in the observable universe.

A good discussion on the greenhouse effect and its influence on warming and cooling the planet is included. Carbon dioxide, water vapour and methane are effective greenhouse gases that trap infrared rays escaping out of the ground and heat it up like a blanket. It is to be remembered here that water vapour is a greater greenhouse gas than carbon dioxide and it is present in huge quantities in the atmosphere. Why then are we concerned only with carbon dioxide, whose share is a minuscule 0.04%? The author does not answer this question. However, greenhouse effect is not all evil. Without it, earth’s surface temperature would be directly related only to the amount of heat it received from the sun and how much it reflected back. Its temperature would then plummet to -18 degree Celsius from the cosy +15 degrees at present. Without this 33 degree temperature rise due to greenhouse effect, higher forms of life would not be possible. At this point, Waltham reminds us that global warming on much larger scales have occurred in the past when carbon dioxide doubled and mean temperature shot up by 8 degree Celsius 250 million years ago. This event is called Permo-Triassic Mass Extinction and was caused by volcanic eruptions that covered much of present-day Siberia. It killed off 95% of marine life and 70% of terrestrial species. Luckily, evolution had only reached the level of trilobites by that time. Five such events have occurred in the history of life. In each disaster, a substantial fraction of existing species died out to be replaced over the next 5 to 10 million years by new animals and plants that evolved from the survivors. Temperature is claimed to have oscillated from -50 degrees Celsius to +50 degrees Celsius – a change of 100 degrees in all. Anyhow, in the last 500 million years when visible life proliferated on the face of the earth, the swing has been a more modest 10 degrees.

Waltham worked in the oil sector in his professional career and confesses to receive funding from oil corporates for his research. One would then naturally conclude that he would cast aspersions or question global warming. He does nothing of the sort. Not only that, he lends support to calculational models used by climate change speculators and declares that he is not able to find much flaw in the software models employed by global warming proponents. There are great uncertainties in the prediction of future temperature changes but even very optimistic assumptions predict major difficulties ahead. So, global warming is here to stay!

We are now obsessed with carbon dioxide levels in the atmosphere and the temperature spikes it can cause. This book presents a lot of astronomical issues that can wreak great disasters. Earth's axis is wobbling in space and its orbital elongation is sometimes affected by the gravitational pull of other planets. There are definite astronomical cycles that contribute to periodic heating and cooling of the planets. These have typically large periods like 41000 or 100000 years. It may come as a surprise to know that throughout the majority of earth's history, our planet has been much warmer than today and almost completely free of any sea ice. We are now living through a slightly warm inter-glacial period that separates one ice age in the past, around 11000 years ago and another ice age in the future.

Any discourse on climate balancing by the biosphere would not be complete without a mention of James Lovelock’s Gaia theory. Lovelock postulated a complex interaction between earth’s life forms and its climate using feedback mechanisms that help to stabilize the weather. However, Waltham is not very enthusiastic about it, blaming the hypothesis of its lack of unambiguous observational support and significant theoretical difficulties. An attack on a more fundamental level is made when the author warns that Gaia proponents might have got the cause and effect totally wrong. Instead of theorising that life contributes to a stable climate, it might well be possible that life became viable only due to environmental stability.

Waltham has incorporated a very long discussion on cosmology in which the physical laws and constants support life in this universe. This rakes up the issue of whether multiple universes or multiverses are possible, which is a favourite topic of popular science authors. But this won't further our ideas on the subject matter because what is known is so few and most of the ideas are only intelligent guesses at best or mere conjectures at worst. This narrative goes nowhere. The author asks the readers to make use of the internet for viewing pictures of other planets and stars mentioned in the book rather than looking through available telescopes which are of much poor quality then we expect. The book is easy to read but no point is made by the author because he claims that all life on earth is due to nothing but luck or good fortune. This is an extension of the anthropic principle. The saving grace is that he does not attribute divine intervention at any stage. Even then, it is to be doubted that he has left that final step in the argument for the readers to make out between the lines.

The book is recommended.

Rating: 3 Star