As for temperature, the warming was also more complex than a simple upwards rise. There was a rapid rise to current temperatures at 14,500 years ago, and then a remorseless drop to ice age temperatures by 13,000 years ago. Then temperatures rose to current levels by 10,000 years ago - and have remained essentially flat since then.
This evidence from ice cores is supported by studies of vegetation changes around the world, including Australia.
In the fact the massive, and rapid global warming at the end of the last ice age has never been properly explained.
Were the Upper Palaeolithic people in Europe and the Aborigines in Australia burning fossil fuels? Or were there aliens from outer space plundering and burning Earth's resources of fossil fuels on a scale unmatched by China today?
IMO a possible explanation for these wild fluctuations is that there was some reduction in solar heat output, and then an increase. Or possibly the ice ages represent some entry to, and exit from, interstellar dust.
With no plausible explanation for rapid temperature changes (incidentally the evidence for the onset of ice ages is also rapid) then the prospects of a new ice age are real.
It indicates that temperature has been steadily declining since the onset of the current warm period some 1o,000 years ago. In fact the decline looks horribly like the pattern at the onset of the last ice age some 120,000 years ago.
How does this relate to oil?
An argument can be advanced that global cooling would have a more catastrophic environmental effect on humans than a warming event. The world of the last ice age was a cold, bleak and dusty event, making the northern Americas, Europe and Asia unhabitable.
So IF (and it's a big if IMO) increased carbon dioxide levels increases global warming then it might help proof the northern Americas, Europe and Asia against the catastrophic effects of another ice age.
My overall opinion is that we should avoid squandering fossil fuels, but for reasons that relate to saving resources for the future and not for the hope of 'fighting climate change' - whatever that vague phrase means.
FAR Price at posting:
6.9¢ Sentiment: Buy Disclosure: Held
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