Report 7, 04/08/2023
The Earth’s Carrying Capacity and Safe Operations of Ecological Systems
The Global Global Footprint Network has graphed the Earth’s biocapacity or the difference between the ability of the Earth to absorb changes in six major categories of use–grazing and agricultural lands, fishing grounds, forests, built-up areas, and CO2 emissions. In 1970, and in all subsequent years, the biocapacity of the Earth has been exceeded. Where once the Earth had biological reserves, it now has an increasing deficit as the biocapacity has steadily declined. Today the Earth’s ecological exceeds its biocapacity by 40%. And, if everyone lived as we do in the United States, it would take six Earths not to exceed its biocapacity. Only Canada, Russia, Australia and some parts of Africa and South America still have large areas of biological reserves.
Since 2016, all categories of land use have been increasing. The carbon footprint (determined by the inability of the Earth to absorb CO2, as described below) has increased most rapidly. The demand for cropland had also increased significantly. Continued downward levels in biocapacity caused by population increases and demands for more goods and services can only result in greater deficits in the global ecological footprint.
Another way of seeing the human impact on the Earth has been made by the Swedish Resilience Center. Researchers at the University of Stockholm have studied ten or more of the Earth’s major ecological systems to determine if they are operating at “safe levels”. Climate change, regional biodiversity, changes in land use, the levels of phosphorus and nitrogen, and the availability of green water are all at or above unsafe levels. Ocean acidification is approaching unsafe levels. Although climate change has been most studied and publicized, it is but the tip of the ecological changes that are at increasing risk of further negative change. Other systems such as plastics and chemicals in the land, sea, and air were originally classified as novel entries.
https://www.pnas.org/doi/10.1073/pnas.1810141115
. Credit: “Azote for Stockholm Resilience Centre, based on analysis in Wang-Erlandsson et al 2022”
