I and my colleagues have spent a decade or more trying to get a handle on tipping points in complex systems. A tipping point is when something changes rapidly to a new state - like water turning to ice at zero degrees Celsius, or when a virus bubbling around in a population suddenly explodes into an epidemic, as if from nowhere.

We’ve been looking for signs – early warning signals – of approaching tipping points. This could help us predict if an ecosystem or banking system is about to collapse. But what we have found is perhaps even more profound and worrying. Industrialised societies are pushing Earth towards potentially irreversible tipping points. The world must pull back from the brink.

Luckily, there are strong signals that the global economy is on the cusp of another tipping point. The world, it seems, is moving decisively away from this destructive pathway towards one of global sustainability.

This news comes not a moment too soon. Climate change is no longer some distant risk to future generations. It is here and now.

Global climate tipping points - can we avert disaster?
Global climate tipping points - can we avert disaster?
Image: University of East Anglia

Welcome to the age of humans

Hurricane Harvey intensified rapidly and brought record rainfall to Houston. Hurricane Irma’s record longevity at Category 5 strength allowed it to crush all in its path. Over six million residents in Florida were ordered to evacuate. And in Asia, 41 million were affected as Bangladesh sank beneath the worst floods in a century, their farms and housing ruined.

While hurricanes and monsoons occur naturally, of course, their increasing strength and ferocity have our fingerprints all over them. Emissions of greenhouse gases warm the planet, altering the carbon and water cycles. A warmer ocean stores more heat, providing more fuel for hurricanes. A warmer atmosphere holds more water, bringing dangerous deluges. Rising sea levels threaten coastal zones.

The changing climate may also extend the length of hurricane season and cause hurricanes to stall in one place. Hurricanes may also stray farther north and south of the equator in a warmer world, but the science in these areas is less certain. Away from floods and storms, dry areas are set to get drier. This will likely mean longer droughts and more fires.

This is just the beginning of our journey into the Anthropocene era – the age of humans.

Floods and hurricanes are the tip of the iceberg

Understanding tipping points is crucial for grasping what is at stake. We take a stable climate for granted. Growing seasons are largely predictable. We know when we can expect the start of the dry seasons and monsoons. We are used to sea levels as they are.

This relative stability provided by a resilient Earth has lasted 10,000 years. It allowed the first agriculture and civilisations to emerge from the fertile plains of Mesopotamia and Asia. We can say that Earth’s resilience – its homeostasis-like ability to remain within certain boundaries – is our common heritage and every child’s birthright. Earth resilience is the ultimate global commons. We can also now say with confidence that this global commons is at risk.

Events in Asia and the US are the tip of the iceberg. They also expose a fundamental flaw in our thinking about solutions. Economists often argue that environmental destruction is a necessary evil on the way to prosperity. Once a nation is rich, the middle classes demand lower pollution, which is possible to deal with because money is there to solve it. In the Anthropocene this logic no longer applies. Even the wealth of the US cannot protect against the levels of environmental destruction that we are unleashing.

This story goes beyond climate. Other ways that industrialised societies are affecting the global commons include habitat destruction and the mass extinction of species, pollution of nitrogen and phosphorus from fertilisers leading to dead zones, ozone depletion and ocean acidification.

A fresh focus

Over the last two years, I have been working with an international group led by the Global Environment Facility, the World Economic Forum, the International Union for the Conservation of Nature (IUCN) and the World Resources Institute to seek adequate responses to protect the new global commons and avoid crossing dangerous tipping points. On this journey we have begun to articulate what is needed.

Protecting the global commons must become the number one priority. The megatrends where we need immediate action are energy, food production, urbanisation, consumption and production.

But we need more. The world needs science-based targets to support the global commons. And we need a new narrative for humanity as a global species in control of its long-term destiny.

The good news is that the worldview is shifting perceptibly towards planetary stewardship and responsible management of the global commons.

A safe space for humanity

On energy we are seeing early signs of an economic tipping point approaching. Global emissions of carbon dioxide appear to be stalling. India, the UK, France, the Netherlands and Norway have announced plans to end sale of diesel and petrol cars. China and Germany are expected to follow soon. Renewable energy is on an exponential growth trajectory. But success will require the collapse of the carbon industry overnight. Greenhouse gas emissions need to halve every decade globally to 2050.

Here, too, we can see the right level of ambition emerging. There is growing evidence, reported recently in the Financial Times, that institutional investment funds that observe environmental and social standards “tend to outperform those that don’t by a significant margin”. The report goes on to warn that anyone foolish enough to have invested in US coal in June 2014 would have lost 85% by the end of 2015.

To remain on this trajectory, we need a global mindshift towards stewardship of the global commons, new goals for societies that break away from a singular fixation on economic growth at all costs, and new rules of the game. This is why the global commons movement is being launched in New York at the World Economic Forum’s Impact Summit. Behind this launch stands a coalition of organisations committed to driving the transformation required to ensure a resilient and stable Earth.

I am humbled by the commitment and energy of the leaders of these organisations who see the absolute need for transformation to global sustainability within planetary boundaries. We need this movement to swell with more organisations and industry partners, underpinned by science-based targets and new narratives for people and planet. Our aim is no less than to create a tipping point towards a safe operating space for humanity.