One of the
greater challenges we engineers face is telling our clients that their dream
project doesn’t work. If it costs too
much, they usually accept our advice with ill grace. Sometimes, it is technically impossible. Then
they have great difficulty in believing us.
For instance, few will accept our advice that the ideal of creating a
low carbon world within our lifetimes is probably not achievable.
The
evidence that a
low carbon world within our lifetimes is an unachievable dream is clear. In 1998, the then developed nations signed
the Kyoto Protocol, which placed legally binding commitments on them to reduce
their emissions below 1990 levels. Global emissions in 1990 were 22.6 billion
tons of carbon dioxide (CO2). Fossil fuels made up 88% of the primary energy
supply. In 2012, when the first Kyoto commitment period came to an end, global
emissions were 34.5 billion tons, over half as much again as in 1990, and
fossil fuels made up 87% of the primary energy.
So much for legally binding commitments!
Of course, the
developing nations did not foresee the rapid development of China. That put paid to the Kyoto ambitions. Recently, there has been much cheering about
China’s offer to start reducing its emissions after 2030. It is perhaps not as encouraging as at first
appears. Today China emits nearly 10 billion tons; business-as-usual until 2030
will see its emissions rise to nearly 18 billion tons.
And if the
development of China was overlooked, then the possible similar surge in India’s
emissions seems to have been forgotten. India has rejected outright any similar
offer to reduce its future emissions, citing the need to develop its economy
before it can take such a step. Today India emits about 2 billion tons; by 2030
it is likely to be emitting over 5 billion, and rising rapidly.
So the
dream appears unachievable. The question
is then whether it will turn into a nightmare.
There are many who claim that a higher carbon world will be wracked by
disaster. In this scenario, the seas will rise, storms will rage, drought will
strike, and the biosphere will disappear. These are the predictions of many
climate models. While all agree that the models are not very good, the question
has to be asked – Suppose the models are right?
Back to the
engineers. Today, humanity depends on us
engineers to provide the defences against the seas, floods, droughts and even
fires and earthquakes. Generally we do
quite a good job. Many people stay warm
and dry, have enough to eat and drink, and rarely experience the disaster of
fires or earthquakes. Of course, our
solutions come with a cost, and there are some who are still trapped in poverty
whom we have not yet found ways to save.
But this is largely a social problem. We engineers recognise that while
we can make a contribution, poverty is not something we alone can solve.
If this is
the state of the world today, then the disaster scenario predicted by the
climate models implies that the defences we engineers have built will be found
wanting. In this case, to address the
risks, we need to enquire where the existing defences may be too weak to
withstand a fiercer onslaught.
Will the seas rise and drown our cities? The Dutch have done a good job of teaching the world how to live normally below sea level, so that is not an insuperable problem. Will there be greater floods than ever known? Generally engineers design for a one-in-a-hundred-year flood. If we start to get more than that, we should have some time to improve the design to cope with the new one-in-a-hundred. Will droughts strike with greater frequency and severity? Our water supplies are already reasonably robust, and over half our water is used quite inefficiently for agriculture. It seems likely that we could withstand more extensive drought, particularly if supplies can be boosted.
Will the seas rise and drown our cities? The Dutch have done a good job of teaching the world how to live normally below sea level, so that is not an insuperable problem. Will there be greater floods than ever known? Generally engineers design for a one-in-a-hundred-year flood. If we start to get more than that, we should have some time to improve the design to cope with the new one-in-a-hundred. Will droughts strike with greater frequency and severity? Our water supplies are already reasonably robust, and over half our water is used quite inefficiently for agriculture. It seems likely that we could withstand more extensive drought, particularly if supplies can be boosted.
This is the
basic message that seems to have been lost in the panic about the risks of
climate change – we already have a high degree of resilience against the
climate, thanks to generations of engineers working in the service of
humanity. That resilience needs maintenance
if it is to continue to provide the desired level of protection. It may need
reinforcement if the climate should become more extreme. But the risks presented by climate change are
by no means insuperable. The costs are most unlikely to be as excessive as some
doomsayers would have us believe.
Moreover,
some of the benefits of more carbon dioxide in the atmosphere should not be
overlooked. Satellite images show the
world greening and deserts retreating. Many European greenhouses are being
controlled at over 1000 parts per million CO2, two-and-a-half times
atmospheric levels. This has been found to boost vegetable and fruit production
very significantly.
So the risks that climate change may prove
unduly destructive are almost certainly overstated, while the supposed driver
of climate change, carbon dioxide, is proving beneficial to life. The proposed
“solutions” to climate change, such as carbon taxes, can now be seen to be the
chimeras they really are.
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