Losing it – the consequences of stepping over the threshold

By David Salt

In Australia, we called the horrible summer of 2019/20 the Black Summer. Unprecedented heat waves and drought led to the biggest, most ferocious, most extensive wildfires this nation had ever known.

I wonder what the world will call 2022? Once again that word ‘unprecedented’ gets rolled out to describe a series of heatwaves, extreme storms, massive floods and record-breaking droughts. This year these events were happening all over the world (and especially across Europe, Asia and America during the northern hemisphere summer). Will it be the ‘Angry Summer’ or the ‘Season of our Great Discontent’ or maybe just the year of ‘Climate Breakdown’. (At what point do we know it’s broken?)

Or maybe the climate disruption will just continue and even grow worse, as many climate scientists are predicting, and 2022 will be wilfully forgotten as we struggle to deal with each new emerging weather crisis.

The idea of normal

When describing abnormal events, unprecedented episodes or historic happenings, you need to have some idea about what ‘normal’ actually means. In some cases this is relatively straightforward.

We have temperature records, for example, that go back for at least a century so it’s easy to define ‘normal’ with statistical precision. Our temperature has ranged between X and Y, and there is a different average max and minimum value for each month of the year. This August was particularly hot for many regions in the northern hemisphere, so when you hear on the news that temperatures broke records, or were above average, you can appreciate just what is meant.

The more variables you bring in (precipitation, wind speed, humidity, wild storms etc), the harder it is to characterise what is normal. Of course, these variables are what add up to weather, and long-term average weather is what we call climate.

If the weather gets ugly, we normally console ourselves that we just need to survive this rough patch and at some point the weather will ‘return to normal’ – the rains will replenish the dams after the drought or calm will follow the big storm.

‘Return to normal’ is a form of equilibrium thinking. Your world gets rocked by some disturbance, your equilibrium is thrown out, but you do everything you can to bounce back, to return to normal.

Of course, I’m talking about the notion of resilience – the capacity to cope with disturbance and bounce back (the word ‘resilience’ derives from the Latin ‘resilire’, meaning ‘to jump back’ or ‘to recoil’).

What’s normal for a complex system

‘Resilience thinking’ is all about how this idea of ‘recovery’ applies to complex adaptive systems. Complex systems have the capacity to self-organise. Resilience is the amount of disturbance a system can absorb and still retain its identity, still continue to function in much the same kind of way.

In recent blogs I’ve attempted explain what complexity means, and how complex systems change over time, how they go through a pattern known as an adaptive cycle. The concept of adaptive cycles is one important building block of resilience thinking, the other is the idea of ‘thresholds’.

There are limits to how much a complex system can be changed and still recover. Beyond those limits the system functions differently because some critical feedback process has changed. These limits are known as thresholds.

When a complex system crosses a threshold it is said to have crossed into another ‘regime’ of the system (also called a ‘stability domain’ or ‘basin of attraction’). It now behaves in a different way – it has a different identity (or you might say it has lost its original identity).

In coral reefs there’s a threshold on the variable of the level of nutrients in the surrounding water. If nutrients become too high, the coral will be displaced by algae. The coral reef identity is lost, replaced by the identity of an algal reef.

On many rangelands there is a threshold on the amount of grass present. If the grass level falls below a certain level (because of too many grazing animals or a prolonged drought), shrubs begin to take over. The grassy rangeland identity is lost, replaced by a shrubland.

Sometimes it’s easy to cross back over to the identity you want, sometimes it’s difficult and sometimes it’s impossible.

Tipping points

In a recent blog I discussed how fossil fuel corporations are complex systems. The identity of this system is heavily influenced by quarterly profit statements; more so than any concern they might hold for longer term climate disruption. The levels of the profits in those quarterly statements likely has a threshold point, below which the fossil fuel corporation will likely change its business (eg, take on the identity of a renewables company, maybe) or shut down. Either way, crossing this threshold leads to a change of identity in this system. (Of course, what might put downward pressure on their profits is stronger government regulation or broader community rejection of the cost being imposed on society by the fossil fuel company.)

In my last blog I also said you could view the British Monarchy as being a complex system. Its identity hinges on public acceptance and support over time, something the late Queen Elizabeth II understood and worked with like a pro. Again, its likely a threshold point exists on this variable of public support, below which the Monarchy becomes vulnerable. QEII represented integrity, authenticity, stability and certainty. She had very high levels of social approval (social capital) that has ensured that the system of the Monarchy had resilience, even to the disturbance of her own death, and the Crown passed seamlessly to her son, now King Charles III. But imagine what might have happened if the Queen didn’t have that level of social capital. Or what happens if King Charles squanders that social capital? Smooth successions aren’t always the rule in the UK (or elsewhere), and many countries don’t need Queens (or Kings) to function.

Thresholds occur in many complex systems however they are often described as ‘tipping points’ where they occur in the social domain. In addition to the two examples I just discussed (profit levels and levels of public approval), tipping points might manifest as changes in fashion, voting patterns, riot behaviour, or markets.

Defining a safe operating space

So here is useful way of defining a system. Every system can be described in a variety of ways using a number of variables. The identity of the system can be characterised by an average range of those values. While kept in that range, the system will behave as you expect, be it a business, a monarchy, a coral reef or a rangeland. However, when the system passes a certain level on one of a number of key variables (eg, profit, popularity, nutrients, grass cover) – a threshold or tipping point – the system changes its identity and begins to behave differently (often in strange or undesirable ways).

Or, in other words, you can understand a system’s identity by knowing how much change it can take before that identity is lost, replaced by a different identity.

Not only are thresholds critical to understanding the behaviour of complex systems, they are the basic limits to whatever enterprise you’re responsible for or have an interest in. To use the phrase in a prominent analysis of global-scale thresholds (Rockstrom et al 2009), thresholds define the safe operating space of your system.

And how are we going in keeping our society in a safe operating space? Well, considering our experiences with the Black Summer of 2019 or the Angry Summer of 2022, not so well.

Climate and weather systems are complex systems too. Their current behaviour suggests they have been pushed over critical thresholds and their emerging identity is something quite new, quite destructive and terrible. Allowing the Earth system to cross these thresholds comes with an enormous cost to society, and will sorely test our own resilience as we cruise into an increasingly uncertain future.

Banner image: How much disturbance can your ‘system’ take before it loses its identity? It’s not just the intensity of a specific event (a single hurricane for example) that’s important, it’s also the frequency of such disturbances. The Great Barrier Reef can survive mass bleaching events if they only occur once every 20 years but it loses its ‘identity’ if they occur every few years (which is now what’s happening). (Image by David Mark from Pixabay)