We introduce the new idea of the “Planetary Boundaries”. The concept was suggested in 2009 by Rockstrom and colleagues from the Stockholm Resilience Institute. The idea is that humankind must struggle for keeping some environmental conditions of planet Earth within a limited range of values, if we – humans – want to keep living more or less comfortably (they said “safely”) in our planet. For each planetary boundary, they set a threshold for a representative variable, which should not be crossed if we want to avoid irreversible changes and harmful consequences.
Nine planetary boundaries are suggested, and most of them will be addressed in the Master’s degree. In particular, we further study some of these boundaries: climate change, ocean acidification, freshwater use and availability, stratospheric ozone depletion, and, in a secondary way, atmospheric aerosol and “novel” entities (namely, electromagnetic pollution).