Undoubtedly, access to fossil energy resources is primarily responsible for the progress to which humankind owes its immense prosperity today, at least in large parts of the world. Let us not forget that, by current standards, we must regard almost all people as having been poor before the beginning of the industrial revolution. They were at the mercy of failed harvests and epidemics without the ability to exert much control, they lived relatively short lives on average, and they existed mostly within a narrowly limited horizon and sphere of influence. The fossil age has catapulted us into the comfort of a modern age whose equipment requires the sufficient and inexpensive availability of energy. Let us also not forget, however, that this was and is only possible at the expense incurred by enormous overexploitation. Fossil fuels are nothing more than the geological storage form of biomass. They contain the accumulated energy from roughly 500 million years of photosynthesis. This sounds reassuring, but it is not: "The fossil fuels consumed between 1950 and 2010 corresponded to 50 to 150 million years of stored sunshine" (McNeill and Engelke 2013).
Fossil reserves
Fossil reserves are therefore not unlimited: we are approaching the peak of their exploitation (. Fig. 1). According to the findings of the Federal Institute for Geosciences and Natural Resources (BGR), "there are still enormous amounts of fossil energy that can, from a geological point of view, also cover an increasing demand for energy" (BGR 2015), but crude oil is "the only non-renewable energy resource for which rising demand can probably no longer be met in the coming decades." Overall, more crude oil energy has already been consumed worldwide than is currently reported in conventional reserves (180 vs. 171 billion t).
Fossil fuels
Therefore, although fossil fuels will not become scarce in the near future and will still be available at least through the twentyfirst century (beyond that in the case of coal), it would be better to use them more and more sparingly. Their use has increased the prosperity of mankind, but it has also had a considerable impact on the environment. These include local, massive interventions in landscapes such as open-cast mines, oil and gas fields, where concentrated fossil fuels occur – in the industrialized countries themselves, but also, for example, in the destruction of the Niger Delta and the rainforests of Ecuador. Even today, despite much stricter safety standards, oil spills still occur along the transport routes, and, on a global scale, air pollution, smog, acid rain and climate change result from the use of raw fossil materials. In an ambivalent dynamic, the use of raw fossil materials has opened up an epoch to which can be attributed its own geological dimension: the Anthropocene, in which humankind, through profound interventions, has become the determining force in shaping and changing the earth. First proposed in 1873 by the Italian geologist Antonio Stoppani, the term became popular only around the year 2000, thanks to the atmospheric chemist Paul Crutzen, who was awarded a Nobel Prize in Chemistry in 1995 for his contribution to the discovery of the hole in the ozone layer: "It seems appropriate to assign the term ‘Anthropocene’ to the present, in many ways human-dominated, geological epoch, supplementing the Holocene – the warm period of the past 10-12 millennia. The Anthropocene could be said to have started in the latter part of the eighteenth century, when analyses of air trapped in polar ice showed the beginning of growing global concentrations of carbon dioxide and methane. This date also happens to coincide with James Watt’s design of the steam engine in 1784" (Crutzen 2002).
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| . Fig. 1 Today’s economy and prosperity are based on fossil resources deposited during geological periods. Fossil coal and energy resources are finite. We are therefore currently at the peak of the fossil age, which will one day represent only a brief epoch in human history (Schurr 2015) |
Fossil materials
The anthropogenically induced increase in carbon dioxide and other greenhouse gases would thus be a characteristic feature of the Anthropocene, and climate change was one of its culmination points. Before the beginning of the Industrial Revolution, the concentration of carbon dioxide in the atmosphere was about 280 ppm; today, it is about 385 ppm. By far, the largest portion of this increase was caused by the combustion of raw fossil materials. Since the beginning of its targeted measurement in 1958 alone, carbon dioxide concentration has risen by around 80 ppm (. Fig. 2).
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| . Fig. 2 Development of CO2 -content of the atmosphere in ppm since the beginning of its measurement in 1958 at the Mauna Loa Observatory in Hawaii. The sawtooth pattern of the measurement results is seasonal. During the summer months, the atmosphere contains less carbon dioxide, because more of it is stored in the leaves of trees and bushes. (© Delorme 2015, CC BY-SA 4.0, 7 https:// commons. wikimedia. org/wiki/ File:Mauna_Loa_CO2_monthly_ mean_concentration. svg) |
The greenhouse effect, which is mainly due to the increase in carbon dioxide emissions, has, in all probability, caused the average warming of the earth’s atmosphere near the surface by 0.8 °C compared with the pre-industrial era in the last decades of the twentieth century. According to NASA, the first decade of the twenty-first century was warmer than any previous decade documented. Many scientists are convinced that the consequences of this warming are already being felt, e.g., through the melting of glaciers: "The potential risks of climate change are numerous, but none is more alarming than the upheavals in the global water balance. Atmospheric warming is likely to change many of the planet’s ecosystems, alter precipitation patterns, cause more frequent and extreme weather events, raise sea levels and flood coasts, adversely affect biodiversity, promote the spread of infectious diseases, cause more heat-related deaths and much more" (McNeill and Engelke 2013). For good reason, international climate policy has therefore set itself the goal of strictly limiting global warming in relation to the temperature at the beginning of industrialization – to a maximum of 2°C, if possible, or even 1.5 °C, as agreed upon at the world climate conference in Paris in December 2015. But this goal can only be achieved if 70% of all available reserves of coal and a third of the oil and gas remain underground and are never used (IPCC 2014).
Energy sources
To counter global warming with a sustainable containment policy is therefore one of mankind’s most urgent tasks in the Anthropocene, which Crutzen defines even more comprehensively: "Unless there is a global catastrophe – a meteorite impact, a world war or a pandemic – mankind will remain a major environmental force for many millennia. A daunting task lies ahead for scientists and engineers to guide society towards environmentally sustainable management during the era of the Anthropocene" (Crutzen 2002). The most promising and ultimately unavoidable way forward in this situation is the gradual transition to an economy based on renewable energy sources and raw materials. To this end, renewable raw materials will be of central importance as sources of carbon that can be used for energy and material purposes and will establish the modern bioeconomy. Although resource scarcity justifies this transition only in the medium to long term, climate and environmental reasons make it necessary in the short to medium term. Even though the oil-based and bio-based economies are likely to continue to exist in parallel as complementary forms of the world economy for many decades to come, it is high time to pave the way for sustainable bio-economies. However, just as there exist many facets of the fossil-based economy today, so will there be many different facets to the bioeconomy in the future. Both embody a principle that has developed or will develop differently in different countries and regions of the world in political, economic and social terms.