This article reviews the changes needed to feed more people sustainably with what we have and points to 9 limits we cannot exceed:
- acid in our oceans,
- ozone depletion,
- fresh water,
- biodiversity,
- nitrogen and phosphorus cycles,
- land use,
- climate change,
- air pollution,
- chemical pollution.
Gerten’s team looked at the four boundaries that are relevant to farming: not using too much nitrogen, which causes dead zones in lakes and oceans; not taking too much fresh water from rivers; not cutting down too much forest; and maintaining biodiversity.
Our population is still increasing and we continue to create CO2 beyond our ability to keep an even balance