Culture
A book that casts the ocean as an extraordinary giant engine helps us grasp its complex physics and its key role in climate change, finds Graham Lawton
Book
Blue Machine: How the ocean shapes our world
Helen Czerski
Torva
WHEN you stand next to the ocean, it is easy to forget that it is connected to every other bit of blue on the planet. If you were so inclined, you could sail from your nearest port through every sea and ocean on Earth without ever making landfall. As ocean physicist Helen Czerski reminds us in her fascinating book, Blue Machine, the ocean is huge, covering 71 per cent of Earth’s surface and containing 96 per cent of its water.
But what we often fail to appreciate is how vastly important it is for the workings of the rest of Earth’s systems, including its atmosphere, ice, land and life. We have a view of our home planet that is still dominated by land and that largely regards the oceans as the salty, wet bits in between. This is, of course, not a new observation. Photographs from the Apollo missions of the late 1960s and early 1970s had a profound impact on our view of the planet, inspiring the famous quote-cum-cliché: “how inappropriate is it to call this planet Earth when it is quite clearly ocean”. (Czerski avoids this, probably in the knowledge that, although it is usually attributed to science fiction writer Arthur C. Clarke, nobody can definitively point to where or when he said it.)
But, in Czerski’s hands, the incredible reality of Planet Ocean really comes alive. Much writing about the mysteries of the deep focuses on its weird and wonderful biodiversity, yet it turns out that the physics of the ocean is just as fascinating. And, while Czerski does throw us plenty of biology bones, this is really a book about the ocean’s physical features – submarine mountains, volcanoes and waterfalls, deep ocean trenches and the endless abyssal plains – as well as the vast forces that shape the water above them.
Chief among these forces is the heat from the sun, but its light is also involved, as is the rotation of Earth and the salinity and density of the water. Czerski explains how these combine with each other to create a dynamic system that she calls the “blue engine”.
It wasn’t immediately obvious to me what she meant, but Czerski explains that the ocean does what any engine does: it converts one form of energy, usually heat, into movement.
And that engine has
