1. CO2 emissions

For the last few million years, CO ₂ emissions have been natural (decomposition of organic matter, ocean discharges, plant and animal respiration) and absorbed by natural CO ₂ sinks (photosynthesis in particular). But the entry into the industrial era, at the beginning of the 18th century, led to the disruption of the fragile balance that had existed until then, and human emissions of CO ₂ then continued to grow, reaching a level of 37 billion tonnes per year in 2019, from the combustion of fossil fuels. This figure may not appear significant, but to show how fragile the balance is and how an imbalance can have major consequences, we need only be aware of the scale of the recent damage caused by current climate change when emissions from soil organisms...