Much print, digital text, and air (some of it hot) has been
expended on the issue of oil, gas and other fossil fuels. We have carbon
capture and carbon trading. We have protocols such as Kyoto and attempts at
improving them such as the Copenhagen conference (generally considered a
fiasco). We have those who toe the line and those (now subject to an almost
religious intolerance) who are seen as, or identify themselves as, sceptics.
“Global warming” may or may not be caused, or exacerbated,
by human use of fossil fuels. Evidence from recent centuries (the short-term
view, you might say) appears to be conclusive. Carbon dioxide and temperature
levels started to rise at almost exactly the same time that the Industrial
Revolution began in Europe. But paleoclimatologists (taking the long-term view)
seem less certain. Of the two measures, the former appears more significant, in
that carbon dioxide is now at an all-time atmospheric high, where temperature
is less easy to determine from proxies. There is good evidence that the
so-called Holocene Climatic Optimum of around eight thousand years ago involved
temperatures higher than those we have today, and it seems very likely that
temperatures about 120 kya (thousand years ago), when tropical animals roamed
southern England not long before the onset of the last Ice Age, were at least 2̊C higher than today. There is also
the possibility that global warming has been caused by increased solar activity,
which occurred during the same 150-year time period. That activity has now largely died away,
giving us an excellent opportunity to see whether temperatures now fall, or
whether (with carbon dioxide levels continuing high) they continue to rise at
the same rate as before. Carbon dioxide levels in the atmosphere should, if the
Gaia system of checks and balances
were working properly, be lowered by the absorption of CO2 by the
oceans, and the fact that the oceans are presently CO2 saturated may have something to do with the horrendous
abuse of the marine environment that has occurred over much the same period as
industrial pollution of the atmosphere and soil, so could be a factor too.
Until very recently (in historical terms – I mean, less than
50 years ago), scientists were convinced that long-term solar system rhythms
meant that we would soon be faced with a renewed icy period comparable to the
Pleistocene. Those rhythms still exist, and presumably would reinstate
themselves if we managed to lower carbon dioxe levels sufficiently – so the question we should be asking ourselves is whether our (very
short-term, in geological time terms) use of fossil fuels is likely to raise
carbon dioxide levels sufficiently to offset the solar system rhythms and continue the upward movement in
temperatures.
But that raises another question. If fossil fuel use raises
carbon dioxide levels, and those levels prevent us entering another Ice Age, is
this a good or a bad thing? On the one hand, burning fossil fuels might be all that is preventing the onset of another
Pleistocene-type episode. In which case, perhaps we shouldn’t be quite so
worried about it, because if we stop burning them, the Ice Age tendency may reassert itself.
And whilst the prospect of warming, with rising sea levels and possibly more
chaotic and extreme climatic conditions, is bad enough, it’s nothing to what we
shall face if we are assailed by another Ice Age, in which drought as well as
cold, and probably violently fluctuating weather conditions to boot, if the
climatic proxy evidence from the Pleistocene is correct!
But on the other hand if it gets really cold, we shall need some fuel to
warm our benighted cities and probably to provide greenhouse heating for the
food plants that won’t grow nearly so well outside. Which fuel shall we use?
Solar will probably be helpful, as there will be more sunshine and fewer
clouds, and there may be violent storms with winds and waves we might utilize
for power. But surely, surely, the best, most concentrated form of fuel that
past ages has bequeathed us is our much-demonised oil, gas and coal. Let’s conserve
them – not because using them is going to force the Earth into a global warming
spiral, or not only because of that possibility, but because we may need them in the future. If we squander them now, at
a period of warmth and optimal growing conditions, our children or their descendants
will curse us. And with good reason.
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