1- Sustainability Awareness (15-25 years)

Welcome to interactive presentation, created with Publuu. Enjoy the reading!

PLANETARY BOUNDARIES

The planetary boundaries are a set of nine planetary limits that, if exceeded, could lead to abrupt and

irreversible changes to the Earth's systems. These boundaries were frst proposed in 2009 by a group of

scientists led by Johan Rockström and are based on scientifc knowledge and evidence about the functioning

of the planet's ecosystems and the consequences of human activities on these systems.

• Climate change

• Loss of biosphere integrity (biodiversity

loss and extinction)

• Stratospheric ozone depletion

• Ocean acidifcation

• Biogeochemical fows (phosphorus and

nitrogen cycles)

• Land-system change (including

deforestation and urbanization)

• Freshwater use

• Atmospheric aerosol loading

(microscopic particles in the air)

• Introduction of novel entities (e.g., toxic

chemicals and radioactive materials)

THE NINE PLANETARY BOUNDARIES

These provide a framework for understanding the limits of the Earth's systems and the potential consequences

of human activities that cross those limits. By staying within the boundaries, we can maintain the stability and

resilience of the planet's ecosystems and ensure a safe operating space for human civilization. On the other

hand, if we exceed the boundaries, we risk irreversible and potentially catastrophic impacts on the Earth's

systems, including changes to the climate, loss of biodiversity, and degradation of essential resources such as

air, water, and soil.

Estimates of how the diferent control variables for seven planetary boundaries have changed from 1950 to

present. The green shaded polygon represents the safe operating space.

• Stratospheric ozone depletion. The stratospheric ozone layer in the atmosphere flters out ultraviolet (UV)

radiation from the sun. If this layer decreases, increasing amounts of UV radiation will reach ground level. This

can cause a higher incidence of skin cancer in humans as well as damage to terrestrial and marine biological

systems. Fortunately, because of the actions taken as a result of the Montreal Protocol, we appear to be on the

path that will allow us to stay within this boundary.

• Loss of biosphere integrity (biodiversity loss and extinctions). The Millennium Ecosystem Assessment of

2005 concluded that changes to ecosystems due to human activities were more rapid in the past 50 years than

at any time in human history, increasing the risks of abrupt and irreversible changes.

• Chemical pollution and the release of novel entities. People are putting harmful and long-lasting

substances into the environment, like synthetic chemicals, heavy metals, and radioactive materials. These

dangerous substances can harm living things and change the environment in a permanent way by afecting the

air and climate.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32