Nine planetary limits: climate change and biodiversity

Today we live in an unprecedented era, in which the global crisis is forcing drastic changes to an established business model. The human impact on a global scale has been so strong that scientists have declared the end of the Olocene, the geological era of low climate variability that characterised the last 10.000 years, to mark the beginning of the Antropocene, in which humans are the main driver of change in natural systems. To shed some light on what is happening scientifically, we refer to the Framework of 9 Planetary Limits, developed by 28 scientists led by Johan Rockström of the Stockholm Resilience Centre and Will Steffen of the Australian National University. This model identifies nine fundamental global processes and their respective limits that, if exceeded, could lead to dramatic changes in the conditions of life on Earth for all living species, including us humans.

The planetary limits are thought of as a kind of 'red line' that defines a safe range within which humanity can operate without causing drastic and potentially irreversible changes in the Earth system. These limits have been conceptualised as 'circles' with three distinct bands:
- Border: this is the safe zone, in which human activity does not cause major destruction or irreversible changes to the environment. It is the optimal level in which we should aim to remain.
- Zone of uncertainty (or risk): this is the zone in which human activity begins to cause concerning and potentially harmful effects.
. - Over the zone of uncertainty: this is the zone of "danger", where human activity has caused drastic and potentially irreversible changes. Crossing this red line means that we have caused damage that may not be repairable and may threaten the survival of life on Earth.

The exceedance of a planetary limit means that we have entered the danger zone, where the damage is deep, far-reaching and potentially irreversible. According to the latest update in 2022, we have already exceeded 6 of these 9 limits (of which 3 are still in the uncertainty zone and 3 are already beyond the uncertainty zone). The planetary limits are so closely interconnected that an increase in one of them can negatively affect the others. For example, chemical pollution or ocean acidification have a negative impact on the loss of biodiversity, just as the climate change can have negative effects on land use. All nine limits are therefore equally important and it is necessary to find solutions both to comply with those that have not yet been exceeded and to turn back the one we have far exceeded, with the aim of not getting even worse.

"For the climate change," Rockström explains, "we chose the atmospheric concentration of the main greenhouse gas, carbon dioxide. We estimated the uncertainty range between 350 and 450 parts per million (ppm), so the planetary limit is 350 ppm." Today, with 420 ppm of carbon dioxide in the atmosphere, we are in the zone of uncertainty: the environmental impact is more than evident and human activity has already caused worrying and harmful effects. The limit has not yet been exceeded, but unfortunately we are approaching the 'danger' zone.

The biodiversity, i.e. the variety of animal and plant species on our planet, has been disappearing at an alarming rate in recent years, in particular due to certain human activities, pollution and the consequences of climate change. The ISPRA recently confirmed this decline, in fact 9% of bees and pollinating insects are at risk of extinction, a situation exacerbated by global warming. "The natural extinction rate is up to 10 species per year," says Rockström, "we set the limit at a frequency ten times higher. But today this rate is about 1,000 species per year, a hundred times higher'. The biodiversity is therefore among the planetary limits already exceeded, with respect to which it is urgent to take concrete action to find solutions that will make it possible to turn back the clock and not get worse.

Can the current model of economic growth be considered sustainable? How do private companies play an essential role in efforts towards an ecological transition? To answer these questions, and more, we launched the project Pillole dall'Oasi: la Digital Academy by 3Bee for Sustainability Professionals, realised in collaboration with Neutralia and Italian Tech Academy. A course composed of 12 modules dedicated to training on topics related to business sustainability, with the involvement of 23 experts from the world of research, innovation, business and finance. An opportunity not only for training, but to join an exclusive community to receive monthly updates on news from the world of sustainability. Do you want to make your commitment to protecting the environment tangible and ensure the best training for your employees?