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Climate Change and its Biological Consequences by David M. Gates, Sinauer,
pp 280, £16.95 pbk

Don’t be confused by the title. This, sadly, is not a global study. Its
scope is almost entirely North American – and largely concerned with the
area south of the 49th parallel. As the author admits in the introduction,
he planned a worldwide review but never fulfilled the brief.

The book is disappointing in other ways, too. Gates’ writing is accessible
and well referenced, but very dull. Especially so when compared with his
namesake Phillip Gates’ delightful British study, Spring Fever, published
last year (Review, 2 May) – which, incidentally, makes a nonsense of David
Gates’ limp claim that there was no work from other countries to allow him
to extend the scope of his own book.

The heart of David Gates’ book is a description of various models of the
likely impact of warming on North American crops, forests and other
ecosystems. Most are deeply flawed, because they are based on simple changes
in average temperatures, and sometimes do not take into account the probably
large changes in rainfall and evaporation.

Gates seems aware of these flaws. He says at one point that ‘vegetation will
change more as a result of rare and extreme events than in response to a
change in average conditions’. And he reinforces it at the beginning of his
chapter on forests by noting that ‘increased storminess – more hurricanes,
tornadoes and down- bursts – will have an enormous impact on forests’. But
the modelling studies he quotes show scant regard for this.

Odder still, he tells us how the great boreal forests of northern Canada and
Siberia – a quarter of the world’s surviving forest – will thrive in the
greenhouse world. But then the final paragraph of this section reveals that
‘a basic assumption of all these calculations’ is that warming happens
slowly enough to allow the forests to adapt to their new climate and migrate
with the isotherms. Unfortunately, almost every study of the pace of climate
change concludes that this is unlikely to be the case. As they say, ‘garbage
in, garbage out’.

Sadly, the workings of modern publishing make it far more likely that
British readers will come across David Gates’ book than that Americans will
stumble on Phillip Gates’ work. This is a loss for both sides of the
Atlantic.