Understanding the Science of Climate Change

A Short Introduction to Climate Change

Tony Eggleton

2013

248pp, paperback

Cambridge University Press, Melbourne

$39.95

ISBN: 9781107618763

Also available as an eBook

Review by David Teather

Type "climate change" into your search engine. Pandora's box opens. Who or what to believe? But the climate is an observable phenomenon. It's been the subject of sustained scientific enquiry for decades. What have scientists really learned about the earth's climate?

After a working life as a geology academic specialising in the weathering of rocks, Emeritus Professor Tony Eggleton, of the Australian National University, approached climate change with an open mind. He wrote this book as a retirement project, and organised his enquiry around key questions: What can change the climate? How has the climate changed in the past? Is the climate changing now? And, if the climate is changing now, is the rate of change normal? What's causing this change? What can be done about it?

Searching for answers, Eggleton takes us on a guided tour through many topics: seasonal changes in animals and plants; temperature records and their accuracy; records of rainfall, storms, droughts and floods; behaviour of mountain glaciers, arctic permafrost, polar sea-ice and icecaps; storage of heat in the oceans; sea level; ocean acidity; geological evidence of temperatures and chemical composition of the atmosphere over millions of years; chemical and physical properties of greenhouse gasses; solar radiation, sunspots and much more. Along the way we get fascinating insights into how scientists work, and why they have confidence in what they know.

As the book develops, the author summarises the "work in progress" that we accept as scientific knowledge. The evidence is inescapable. Not only is the earth's climate getting hotter, but the distribution of rainfall is changing, polar ice is melting, sea level is rising and the oceans are becoming more acidic.

Eggleton found that many factors can initiate and contribute to climate change, and have in past ages done so. But the climate is now changing much faster than at any time during the last two million years (when Homo sapiens first appeared). This exceptionally rapid change is due to a single cause: the emission of greenhouse gasses (primarily carbon dioxide, but also methane) resulting from human activity (primarily burning fossil fuels, but also clearing forests and manufacturing concrete!)

Eggleton searched diligently for scientific evidence and theory that might support contrary views. As a distinguished scientist, he knows what to look for and where to look. He was shocked to find nothing of substance, and demonstrates that the case espoused by those who deny climate change is flimsy indeed. It's puffed up by mass media that thrive by reporting conflict, and supported by those with vested interest in maintaining the status quo.

Returning to the science, Eggleton concludes that global warming risks triggering changes likely to exacerbate the problem to catastrophic proportions: for example, by releasing very large quantities of greenhouse gasses trapped in undersea sediments; and also by melting sea-ice and polar icecaps thereby lowering the reflectivity of the earth's surface which then absorbs more of the sun's heat (rather than reflecting it back into space).

What's to be done? The task is to reduce the concentration of greenhouse gasses in the earth's atmosphere. This means reducing emissions, quickly and safely, taking into account both the risks of climate change and risks inherent in further human intervention in natural systems. The author mentions alternative energy, carbon sequestration and geo-engineering, but reminds us that economics and public policy are outside the scope of his book. For insights on climate change from these perspectives, see "A Blueprint for a Safer Planet" by Nicholas Stern (published in 2009 by The Bodley Head), and Robert Manne's recent article in The Guardian (tinyurl.com/manne-guardian).

Tony Eggleton provides an engaging and expertly informed account of the science of climate change. He gives much-needed coherence to this important and multi-faceted subject. His book deserves a place in every public library, and in libraries of secondary schools, technical institutes, polytechnics and universities. It sits neatly between short summaries, such as "The Science of Climate Change: Questions and Answers" (published in 2010 by the Australian Academy of Science and available at www.science.org.au), and longer works like John Houghton's "Global Warming: The Complete Briefing" (4th edition, 2009, Cambridge University Press).

Chain Reaction #119, Nov 2013, www.foe.org.au/chain-reaction/editions/119