Planetary Boundaries: Assessing Environmental Limits

This lecture discusses the concept of planetary boundaries, which outlines nine critical processes that regulate the stability and resilience of the Earth system. Initially proposed in 2009, the framework has undergone several revisions, with the latest update quantifying all boundaries and revealing that six of the nine have been transgressed. The instructor emphasizes the interconnectedness of these boundaries, highlighting that a singular focus on climate change is insufficient for achieving sustainability. The lecture details the implications of crossing these boundaries, which increases the risk of large-scale environmental changes. It also underscores the importance of understanding the interplay between climate change and biodiversity loss. The planetary boundaries framework has generated significant interest in scientific and policy circles, guiding human development while ensuring the preservation of the Earth’s systems. The lecture concludes with a call for integrated approaches to sustainability that consider the complex interactions within the Earth system.