Boundaries
Towards a planetary boundary framework
In 2009, a team, led by the climate scientist Prof Johan Rockström, identified nine natural processes that regulate Earth’s biosphere and keep it stable. These include climate change, biosphere integrity, land-system change, freshwater change, biogeochemical flows, novel entities, ocean acidification, stratospheric ozone depletion and aerosol loading. For each of these processes the team defined the ...