In 2009, academics Johan Rockström, Will Steffen and colleagues proposed an idea well beyond the geopolitical concept of borders. What they described was the notion of planetary boundaries – a representation of the environment and the overall health of earth systems. They outlined a safe operating space for humanity and warned of immutable environmental tipping points at which potentially dire consequences will present themselves if the planetary boundaries are crossed.

The team identified nine planetary boundaries: biosphere integrity, climate change, novel entities, stratospheric ozone depletion, atmospheric aerosol loading, ocean acidification, biogeochemical flows, freshwater use and land-system change. As expected with a system of this size and complexity, there is a high level of uncertainty about the quantitative values of the tipping points and the defined ranges of safe operating space, as well as uncertainty around humanity’s current quantitative position within these boundaries and trajectory through them. There is also added complexity from the obvious interactions between the boundaries that increases the difficulty of both quantifying them and understanding the ramifications of passing them. For example, land-system change evidently decreases biodiversity, but by how much? And is there an impact on any other boundaries?

Humanity is on a trajectory to reach the predicted tipping points in more than half of the boundary measures

Currently, it is estimated that four of the boundaries have already been crossed – biosphere integrity, climate change, biogeochemical flows and land-system change – with others considered in the zone of uncertainty due to boundary quantification. In short, humanity is on a trajectory to reach the predicted tipping points in more than half of the boundary measures. In some good news, policy interventions and international collaboration have been successful in bringing us back from the brink in the area of stratospheric ozone depletion.

Levels of stratospheric ozone depletion are being addressed by international policy interventions and collaboration (Shyam/Unsplash)

The strategic and security potential of the planetary boundaries framework is extensive. Until recently, the idea had received limited attention but has now entered the public discourse predominantly thanks to a new Netflix documentary hosted by Rockström and Sir David Attenborough. The importance of mapping the boundaries is threefold. First, it provides a comprehensive outline of the major earth systems. Second, quantitative observations and system dynamics can be developed both within and between boundaries (albeit with uncertainty). Third, policy, strategic and security goals naturally evolve from the boundaries and have the potential to provide a clear way forward in the reversal of environmental degradation if appropriately implemented.

With the impacts of climate change and environmental change being experienced at both local and global levels, an increasingly vocal public wants to see action.

By deeply understanding the planetary boundaries and developing accurate quantitative values for humanity’s position within them, policymakers can focus on strategic points of collaboration. This is particularly important when considering the impact that climate change, biodiversity loss, freshwater availability and agricultural output are expected to have on national security and the role of the military in the decades to come. Taking these emerging risks into consideration will lead to better Defence resilience, preparedness and investment in future infrastructure. For Australia, this may mean that several boundaries are more applicable than others, enabling targeted distribution of resources and tailored policy goals.

With the impacts of climate change and environmental change being experienced at both local and global levels, an increasingly vocal public wants to see action. The most recent Lowy Institute Climate Poll found that 60 per cent of Australians say that global warming is a serious and pressing problem. Industry, too, realises the extensive economic risks of not pursuing policy that seeks to mitigate the worst effects of climate change, and with national security factors becoming more apparent, the time is right for the widespread adoption of the planetary boundaries framework.

If adopted correctly and sufficiently, the planetary boundaries framework can provide a clear and accurate environmental roadmap for Australia’s regional and global security interests, ultimately enabling greater levels of resilience and preparedness.