Environmental History

On top of nuclear war, in the coming decades humankind will face a new existential threat that hardly registered on the political radars in 1964 : ecological collapse. Humans are destabilising the global biosphere on multiple fronts. We are taking more and more resources out of the environment, while pumping back into it enormous quantities of waste and poison, thereby changing the composition of the soil, the water and the atmosphere. We are hardly even aware of the myriad ways in which we disrupt the delicate ecological balance that has been shaped over millions of years. Consider, for example, the use of phosphorus as a fertiliser. In small quantities it is an essential nutrient for the growth of plants. But in excessive amounts it becomes toxic. Modern industrial farming is based on artificially fertilising the fields with plenty of phosphorus, but the high-phosphorus run-off from the farms subsequently poisons rivers, lakes and oceans, with a devastating impact on marine life. A farmer growing corn in Iowa might thus inadvertently kill fish in the Gulf of Mexico. As a result of such activities, habitats are degraded, animals and plants are becoming extinct, and entire ecosystems such as the Australian Great Barrier Reef and the Amazon rainforest might be destroyed. For thousands of years Homo sapiens behaved as an ecological serial killer; now it is morphing into an ecological mass murderer. If we continue with our present course it will cause not just the annihilation of a large percentage of all life forms, but it might also sap the foundations of human civilisation. Most threatening of all is the prospect of climate change. Humans have been around for hundreds of thousands of years, and have survived numerous ice ages and warm spells. However, agriculture, cities and complex societies have existed for no more than 10,000 years. During this period, known as the Holocene, Earth's climate has been relatively stable. Any deviation from Holocene standards will present human societies with enormous challenges they never encountered before. It will be like conducting an open-ended experiment on billions of human guinea pigs. Even if human civilisation eventually adapts to the new conditions, who knows how many victims might perish in the process of adaptation.