First published in German in the Basler Zeitung of April 27, 2018
Earth’s history in geological terms can be displayed on a spatial scale of 46 kilometers, whereby every millimeter covers one hundred years. Let’s begin with a depiction of a geological journey starting 46 km away from our home. On the first 40 kilometers, the existence of life on earth commences with the presence of water bound single-cell organisms, which very slowly evolve to primitive multicellular organisms. The climate hitherto cannot be compared to how we experience the current climatic conditions at present. About five kilometers away from home, the occurrence of life suddenly explodes and the majority of plant phyla and animal life begins to evolve. At this point in time, free oxygen in the atmosphere increases to current levels. Photosynthesis of the lush plant life reduced CO2concentrations by orders of magnitudes. Coal seams and hydrocarbons are tiny remnants of that period. This initial era where life begins to flourish, is followed by a period of long-lasting global ice-ages.
Over the last three kilometers on the way home, mammals start to develop; the planet is warm and free of ice. The dinosaurs (for rather unknown reasons) became extinct 600 m before our destination. The relatively cold age of today, which is characterised by icy poles, began 200 m before the finishing line. The first hominids appeared thirty meters on the home stretch and the last ice ages took place on our driveway. Modern man appeared on the last two meters of our time span. The Sumerian and Egyptian high cultures thrived only briefly during 5 centimeters on our scale and the Christian era stretches over the last two centimeters before target. The meter scale illustrates evolutionary time frames in a graphic manner.
To continue with our analogy, we find that the industrial era started three millimeters before our destination. The industrial revolution in the 18th century, which was driven by the discovery and usage of fossil fuels, catapulted the global population from one billion people to over seven billion inhabitants by the turn of the 20th century. This never before witnessed demographic explosion, occurred on the last two millimeters of our pictured time scale. It should come to no surprise, that this sudden population expansion has created an unprecedented environmental impact.
The production of CO2-emissions and the increase in CO2-concentration are only symptoms of the industrial era. In view of our yardstick’s dimensions, it is correct to describe this impact as an “unprecedented” event. However, we need to remember that our ability to analyse the past is limited. We cannot identify all climatic factors within the timeframe of just one millimeter from a distance of ten whole kilometers. Beyond all means, we cannot identify everything that happened in the past. The only thing certain, is that life thrived and evolved throughout all eras and even persisted throughout extreme events such as ice ages; countless volcanic eruptions; and meteorite impacts. Life has proofed to adapt to all kinds of earthly conditions and it is most likely to survive the human incident. In fact, life regulates “system earth” more than we presume.
I certainly do not wish to trivialise the human impact, but I would like to challenge our purely anthropocentric view. Of course, we have to assume our responsibility towards the environment, especially because we depend on it entirely, as our natural habitat. However, from the comparison on spatial scales we learn that the “system earth” is vastly more complex and something we have to treat with great respect. It is irrational to think that we could control this system; in particular, since we are not even capable to look ahead as little as one millimenter, speak one hundred years.