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Here today, gone very soon. Sustainability
(and including a dozen different definitions) is meaningless if divorced from the notion
of time constants of processes. So what is a sustainable definition of
sustainability? This is a lecture in itself but one key point is that the Earth may
cease to be a suitable place for human habitation well before the sun explodes and the
oceans boil. Suppose for the sake of argument this is 100 million years.
Little point then in worrying if we have enough copper to last 200 million. Man's
dominion over the Earth is correctly seen as a brief mistake, an evolutionary error that
has lasted (say) 5,000 years and that which might survive for another 5,000. Within
the time scale of Life on Earth this is the blink of an eye, and probably the right order
for debate.
It may not much matter if 5,000 or 15,000 years is chosen. Only a few issues may be
important at 15,000 when they were inconsequential at 5,000. Sustainability is
primarily about managing the next 5 to 25 years since it is here that the 'make or break'
decisions must be made nationally and (especially) globally. Social and
'equality' issues will take generations to address and many are peripheral to saving
biodiversity. Time scale is also the reason why it may be little use educating
children in ecology in the hope that, one day, they will sort out the mess. For many
major habitats it will then be too late.
Suppose it is desired to maintain the Earth in much its present state of viability (or
better) for another 5,000 years, so that, if social issues can in the interim be resolved,
the Earth will still be worth inhabiting. This would be an incredible
achievement. Industrial man has existed for about 200 years, a mere 4% of
5,000. What would be the priorities for action? Energy demand and habitats are
two areas where there are serious problems. Oil may last only a hundred years, coal
for a thousand or more. Added to the depletion concern that was central in the 1970s
is the belief now that if we burn all available fossil fuels (even at a reduced rate) we
might induce severe and rapid global warming.
Loss of habitats has a time constant of 0 to 10 years. The Asian forests are already
largely gone. South America and Africa will be next. At the 2001 Offwell
Lecture it was emphasised that present government policies are to permit importation of
beef from Bolivia that was raised on 'slash and burn' forest areas, and to the detriment
of UK farming. Cheap meat for the voters overrides all ministerial concern for world
sustainability. This one example spoke volumes about government sincerity. But
what of nuclear power and the 'unsustainable' problem of waste? Engineering
solutions can (we are told) guarantee security of waste prod-ucts for tens of
thousands of years. So what is the problem? This is well beyond the chosen
goal. Will reserves of copper last 5,000 years and without problems arising in
disposal of used material that is not or cannot be recycled? If so there is likewise
no problem.
Creating a sustainable world means in effect altering our consumption of resources
and decimation of habitats to levels commensurate with every resource or system failing to
deliver at or beyond the chosen time (5,000 years hence). Picking a
realistic target rather than 'more or less indefinitely' can help to focus analysis on the
most pressing issues and apportion resources to where they are most needed. Sustainable
development must centre upon changes to economic systems and funding priorities that can
be implemented on a time scale shorter than those characterising key issues for
sustainability. Otherwise, corrections may be facilitated too late, no
matter how much money is ultimately made available. A radically new approach to
short term conservation funding is therefore needed. In the longer term, 50 to 200
years, changes to tax systems and social structures could realign spending patterns and
priorities world-wide.
As an exercise in provocation, the economic benefits of natural systems that now provide
our clean water and air and other 'environmental services' were recently calculated at
around $33 trillion ($33 million million) annually. In the ensuing intellectual
mêlée, this figure was described as a serious underestimate of infinity. The cost
of having to use technology to do what nature now does for free would cripple the world
economy. The other advantage of the natural system is that it is proven to
work. Concern often centres on rain forests, most of which may be deliberately
burned or turned to desert by climate change within 30 years. Yet the plight of
marine ecosystems including the stunningly beautiful coral reefs may be even more
desperate - and they may have an 'economic value' 25 times greater.
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