Fine but, at a time of great turmoil and uncertainty in the actually existing human society, aren’t these minority pursuits? Studying our pre-industrial past isn’t going to help us solve our current problems.
But that would be wrong because understanding how and why humans have faced such crises before is exactly what we need in order to solve our crises – if any kind of solution is possible.
What the past teaches first of all is that we have been lulled into thinking that the benign climatic conditions that have attended our rapid rise from the first farming to the age of social media and resource depletion is somehow our birthright. For the first 190,000 years of our existence, conditions were generally unfavourable. The industrial revolution began in a newly benign (on a geological timescale) Europe which for around 98,000 of the last 110,000 years had been covered in ice much of the time.
Human beings evolved out of necessity in coping with drastic climate reversals. When the climate became more benign the skills honed under adversity were brought to bear on more productive questions and the dramatic rise of civilisation resulted. But in pointing to past climate change we have to confront the simplistic ideas of the global warming deniers.
There is no doubt that we would have to face drastic climate change one day even if we had not conducted the experiment of releasing vast quantities of greenhouse gases. The world has warmed and cooled dramatically in the past without our input and there is no reason to think the future will be any different. Unless – and this is a faint possibility – unless human activity, in Gaia fashion, is actually creating and maintaining the benign conditions that suit us. There is some evidence that this has been the case until the surge in CO2 emissions in the last 150 years. Without burning fossil fuels humanity was probably heading for another ice age. The cycle of alternating ice ages and interglacials was well established before we interfered with it. The last interglacial lasted around 17,000 years and the one we’re living through began around 12,000 years ago. As recently as the 1960s the kind of scientists who today warn about global warming were urging the explosion of a few nuclear weapons at the poles to melt some ice and warm the world up.
But the fear of a new Ice Age in the ’60s was founded on little real data; the position now is very different. A vast amount of data from ice cores and global temperature measurements support the hypothesis of man-made global warming.
Climate change has always driven human development. Agriculture probably developed through necessity; the Industrial revolution in Britain certainly did. So we will have to change: our way of life really is unsustainable.
Climatic disasters in the past such as the Toba volcanic eruption of around 74,000 years ago almost certainly reduced the human population to very low levels. There is no reason to suppose that we won’t have to face extreme conditions like this again. It is sometimes thought that our technology will see us though any such event. But tornados flatten towns in the American mid west every year and forest fires burn out suburbs and there is nothing we can do about them, save evacuate the population in good time, thanks to our satellite surveillance. Japan’s hi tech did not prevent the total erasure of coastal settlements following the tsunami – and here even the warning system didn’t work.
The most obvious effects of global warming are well known: sea level rise inundating coastal settlements, with accompanying acidification of the ocean and loss of shelled creatures and corals; changed patterns of rainfall leading to collapse of agriculture in some regions and mass migration; more violent storms, leading to loss of life and destruction of property on a large scale. But there is a lesser known danger that is beginning to loom larger. It is known from the geological record that ice sheets depress the landmass by hundreds of feet. When the ice melts over land the earth bounces back by a similar degree. Scandinavia is still rising from the loss of the ice sheets 12,000 years ago. Earth movements of this magnitude trigger earthquakes, volcanoes and tsunamis. A rash of volcanic activity could have a devastating impact on agriculture if a nuclear winter scenario developed in which clouds of ash obscured the sun for several years. The toll of earthquakes and tsunamis on human life is already at a high level – greater than this and this sum of human misery would be intense.
The big lesson of the human and climatic past is that if it is possible to avoid provoking such a new geological era of massive climatic instability and increased volcanic activity, we should do so because, if such an era should ensue, we would have no defences against it. As it happens, we do have such a course of action open to us: it is mitigation of carbon dioxide emissions. It is exceeding strange that with this simple equation on the table most of humanity currently is in denial.
It is frequently alleged that there is a deep psychological problem for people with their average lifespan of 80 years in taking geological time scales seriously. Most members of the human species throughout its entire history can only have cared for or understood their own generation and the ones immediately before and after them. As Larkin wrote: “we are not suited to the long perspectives”. But the long perspective I’m talking about has only been known to us for a very short time and in the more rational parts of our mind we must surely be able to understand what it means for us? And it could be that in considering global warming we won’t have to overcome our natural limitations to understand that we must do something now for the sake of the world 50, 100, or several hundred years ahead. Because the increasingly detailed record of climate change shows that the act of global warming that made our world possible – a rise of around 6 degrees C from prevailing Ice Age temperatures – took place in a mere decade. That is how tipping points happen. They tip.