All around us all the time, a silent process is taking place. Plants are fixing the radiant energy of the Sun by the process of photosynthesis. Oliver Morton (https://en.wikipedia.org/wiki/Oliver_Morton_(science_writer)) explains how it all happens. The story of how we came to understand the process is itself interesting. It involves biochemistry, the nuclear physics of isotopes and radioactive decay, the quantum physics of molecular bonding and the interaction of light and electricity, the biophysics of free energy flow through cells and through molecules, crystallography, the molecular biology which allows us to isolate and manipulate individual enzymes.
Morton goes on to describe how photosynthesis has itself developed. Organisms which carry it out have interacted with the Earth’s climate over the last three billion years. It’s a story covering everything from the origin of life to plate tectonics and the spread of grasses over the last few million years.
The author moves on to what he calls the ‘climate/carbon crisis’. Agriculture did have non-trivial impacts on climate, but the real change began with the Industrial Revolution and the vast growth in the consumption of fossil fuels. Huge quantities of carbon , charged with free energy by photosynthesis and then taken out of the biosphere by geological processes over millions of years, are getting burned to release the energy. They are then returned to the biosphere much faster than they can be processed. The result is that the atmospheric carbon dioxide concentration has already drastically increased. Since atmospheric carbon dioxide is good at trapping heat radiated back from the ground, the first-order effect of this is to warm the Earth. The exact effects depend on incredibly complicated feedback processes.
Human global civilization runs on something like 40 terawatts. There is enough fossil fuel to keep going for centuries. But dumping that much carbon into the atmosphere will be a disaster. Tidal and geothermal energy are too localized and small-scale to be global solutions. Nuclear fission looks more attractive when one compares long-lived radioactive waste to long-lived carbon dioxide as a pollutant, but there are very real practical obstacles. All our other options are ultimately solar powered -wind, rivers, photovoltaic devices and biomass. Morton is very hopeful about the last two, and especially about what real molecular engineering might do in the space between photovoltaic plates (high efficiency, but also high cost) and naturally-occurring leaves (low efficiency, but naturally abundant).
This book is an education, a pleasure to read, and full of wonderful things.
Check if this excellent book of popular science is in stock at your local library by consulting the online catalogue at https://www.sllclibrary.co.uk/cgi-bin/spydus.exe/MSGTRN/OPAC/BSEARCH
384 pages in Fourth Estate
First published 2007
ISBN 978-0007171798
Oliver Morton