As a geologist, we are introduced to the concept of uniformitarianism early in our scientific career, namely the principle that “the present is the key to the past”. Our understanding of geological processes is dependent on the assumption that the physical processes we observe now are the same as what operated in the past. As a climate scientist, we throw that in reverse, that the processes that happened in the past can serve as guidance to the phenomena we observe now, and to help us estimate what will happen in the future.
In the geological past, there is a history of extreme changes in climate. It only took about 12,000 years for the ice sheets that covered much of northern North America and Europe to completely disintegrate. In that intervening period, the climate warmed in a generally steady manner, punctuated by transient returns to cold conditions. The causes of this steady warming were changes in orbital forcing, allowing more solar energy to reach the polar regions, combined with increasing carbon dioxide and decreased albedo effects as the ice sheets shrank. The periods when the warming slowed or reversed happened suddenly. The Younger Dryas period, for example, saw a return to glacial conditions, and the ice sheets grew again. The cause of the Younger Dryas is still an open question, but whatever it was, it was very abrupt, possibly caused by the sudden drainage of ice dammed lakes into the Atlantic or the break off of large volumes of ice into the ocean. Looking at longer time scales, that of the Earth, the glacial cycles that have occurred during the past 3 million years ago are very rapid oscillations.
As the atmospheric concentration of CO2 reached 400 PPM last year, a level we will never go below again in the foreseeable future unless some unforeseen technological advance happens, we look to the past to see what this means. The last time CO2 levels were this high was in the Pliocene, some 3 million years ago. Around that time, the Panama isthmus became fully formed, isolating the Pacific Ocean from the Atlantic and completely reorganizing ocean currents. At that time, North America and Europe had yet to be glaciated, and the Greenland Ice Sheet never grew much beyond the mountains on its fringe. The Canadian Arctic, not yet a full archipelago, was covered in vast forests and supported animals like camels and beavers. Sea level was higher, as the ice sheets in Greenland and Antarctica were not as large as present.
Only as CO2 levels fell towards the end of the Pliocene did the first major continental ice sheets started to form in North America and Europe. After that, ice sheets grew and retreated, following orbital changes. At first, the cycles followed roughly 40,000 year periodicity, following obliquity changes (i.e. changes to the Earth’s axial tilt). About one million years ago, the cyclicity changed to 100,000 years, following the eccentricity cycle (i.e. the roundness of the Earth’s orbit around the Sun). However, if atmospheric CO2 levels were high enough, some of these cycles failed to produce large ice sheets. This forcing threshold may only be on the order of 20 PPM. We are now 120 PPM above interglacial levels, making the return to glacial conditions unlikely.
After all the above, it should be pretty clear that I am not just an Earth scientist, but also a student of history. In order to understand the motivations of humanity on the whole, we must look to the past and see how humans behaved before, just as in Earth science. For instance, we knows through the study of history that humans rapidly migrated around the world during the past 400 years, and that there have been atrocities and mass warfare as a result of this, as well as great technological and social advances.
And yet, with the rise of anti-immigrant, anti-science, and quite frankly, anti-fact groups that are seizing power in industrialized countries, it has become clear that we have not been paying attention to history. The only reason why the industrialized world is able to maintain peace is that there is a social contract that the savings of mechanization are passed to all people. This contract has been eroded during the past three decades. The people affected by this are now angry about the loss of their status and are lashing out against the power brokers. These people have been conned – the Trumps and Farages of the world don’t give a shit about the plight of those who are the victims of the mechanization of labour. However, they are easily convinced by the argument that the immigrants are taking away their jobs, or that their jobs are being taken away due to trade agreements with third world countries. It is a convenient scapegoat. With the increases in productivity due to mechanization, the centers of wealth have moved from rural areas to urban areas. The power brokers have been all to happy to cater to urban areas, because it is easier and cheaper. More extreme leaders than exploit the anger of the rural areas by playing on their fears.
It has been almost 30 years since the iron curtain fell, and with the end of the cold war came the end of the constant looming threat of global war. I think without this constant threat, people became more isolated, and happy to ignore their neighbour who might be suffering. As a highly mobile millennial, I am as guilty of this as anyone. I can scarcely remember a time when I was living that it felt like my livelihood was truly threatened. My memories of the Cold War basically start and end with the fall of the Berlin Wall. I can only read about these threats from a textbook or from anecdotes of those who lived through it. Without this existential threat to us all, we no longer feel the need to be united. We are more than happy to pursue our selfish ambitions without a thought to our community.
I do read history though. The rise of authoritarian powers has always been predicated by the wilful disregard for the rights and freedoms of parts of the population of the country. Usually those in power with more noble aims are unable to stop it due to the distrust from the general public, or through sheer incompetence. The United States was one of the first to put in place a structure to prevent authoritarianism – the Constitution. Over time, other checks have been introduced, sometimes at great cost. These include universal suffrage, separation of the bureaucratic, judicial, parliamentary and military branches of the state, having a free and open press and introducing strict political spending limits by individuals. Since World War II, these kind of measures have been pretty successful and preventing tyranny.
What has happened?
So what has gone wrong, why have these checks failed us? I think society in general does not take enough time to reflect upon what happened in the past. Scientists know that raising CO2 will cause the climate change, yet a significant number of non-scientists do not know this is a problem, and even go as far as to suggest that it is fear mongering. Part of the reason this is the case is because most countries do not give a proper mandatory introduction of Earth sciences in school. Where I grew up, if you wanted to learn about Earth sciences, you pretty much had to do it as a major in university.
The same goes for human history. We all are told of he cautionary tales of the rise of Hitler, but how many people were actually taught why Hitler rose? Did they learn about the stalemate that was World War I? Did they learn about the harsh reparations that the Allies imposed on Germany? Did they learn about how the German economy collapsed as a result of these reparations, combined with general incompetence and corruption, and paved the way for the rise of authoritarian power? Though I used Germany as an example, a similar story could be told for the Bolshevik Revolution and the rise of Stalin, Imperial Japan after the death of the Meiji Emperor, Franco Spain, Mussolini Italy, etc. It is not enough that we are told about what happened, the study of history must answer the question “why”.
I think we are at a threshold now. Will we be able to fight back against the rising tide of authoritarianism, and return to the democratic values that have allowed us a long lasting peace? Or have the cogs of our system become rusted, and unable to lower the defences? During the past week we have seen Trump take action to remove the checks on his power, while at the same time people have been marching in the street protesting these actions. Which side will prevail? Alas, history can only tell us so much, but I fear it will get worse before it gets better. The authoritarians will reduce the checks that hamper their power too quickly for people to fight back through legal means.