The Goldilocks Planet
By Jan Zalasiewicz and Mark Williams
Review by Marjolaine (Earth sciences)
Over Earth’s history, the planet has endured a wide range of climates, from arid to humid and from scorching hot to the frozen conditions of “snowball Earth”. And yet miraculously, the conditions have consistently been within a range that supports life. Ever since the first lifeforms, around 3.5 billion years ago, conditions have remained habitable. Earth is a “Goldilocks planet” – not too hot, too cold, too wet or too dry but just right.
In The Goldilocks Planet, Jan Zalasiewicz and Mark Williams outline how the Earth’s climate has varied over its 4.5-billion-year history. They demonstrate how Earth scientists have pieced together this history through proxy methods – obtaining data from rocks, sediments, ice sheets and fossils.
The record is incomplete, obscure and sometimes contradictory. They explain scientists’ struggle to piece together Earth’s complex history using this evidence. Each time, Zalasiewicz and Williams present the data and then rigorously examine the possible hypotheses in an unbiased fashion to come to the most likely conclusion.
I would wholly recommend this book. It offers an overview of the major events and changes in Earth’s history as well as explaining the most significant mechanisms for these changes, including silicate weathering, plate tectonics, and Milankovitch cycles. I read it in the summer of Year 12 and, though it was sometimes a tough read, it provided me with a very good base knowledge of Earth history that gave me confidence before my interviews at Oxford.
Earth’s climate has an impact on everything – the rocks, the landscapes and, of course, life – so understanding how climate has changed over time is relevant to all parts of Earth science. Climate change is a major topic of concern today. As society tries to adapt to changes in temperature, precipitation and sea level, Earth scientists are investigating the intricate feedback loops that result in these changes so that they can advise politicians how best to proceed. An evermore detailed reconstruction of Earth’s climate and the factors that caused its variation over time may provide us with clues to help us deal with modern changes.
The Goldilocks Planet by Jan Zalasiewicz and Mark Williams