By Darren Orf – Popular Mechanics
“Climate change” is a scary, catch-all term that summarizes all the anthropogenic degradation humans are inflicting on the planet. In reality, climate change is only one of the many threats facing the planet.
First introduced in 2009, the Planetary Boundary (PB) concept identifies nine unique thresholds that could spell disaster if humanity crosses them. While climate change is one of the nine boundaries, the list also includes things like biosphere integrity, ozone depletion, ocean acidification, freshwater change, and more. (Of course, what we think of as climate change exacerbates all of these issues, so in a sense, it remains Public Enemy No. 1.)