Changing Planet

Keeping Pace with Climate Change

Tokyo. © Alex Knight

Time to accept that climate risks are here, or how not to enter into a staring competition with a grey rhino.

By Giulio Boccaletti, Chief Strategy Officer, The Nature Conservancy

Most commentators still tend to describe the impacts of climate change on our water resources as something that will happen to us, not something that is happening to us. This future-casting bias begs the question: how would we know if the much advertised risks were finally materializing? And, more importantly, what would we have to do about it?

In 2001 financier-turned-author Nassim Nicholas Taleb popularized the idea of a ‘Black Swan’: an extreme, unpredictable event, outside the realm of experience, so much so that people tend not to plan for it and are only really able to manage it ex-post, after the fact. The metaphor was first introduced some two thousand years ago, when black swans were not known to exist. Much to everyone’s surprise, it turned out they did.

Black Swans are important, unpredictable events that shape society for a long time, such as flu pandemics to 9/11. Once they happen, Black Swans redefine our expectations about what is possible, but the real insight is not about the nature and frequency of Black Swans so much as what society can do about them. The recipe for their management is essentially “keep your eyes open and try to plan for the worst”, and that is largely what catastrophe preparedness looks like.

The misrepresentation of events as Black Swans is equally consequential: a fatalistic use of the black swan metaphor to describe events that are predictable, if rare, results in underestimation of likelihood and lets society off the hook to take responsibility for what it knows will happen. This is particularly endemic with public perception of meteorological risks: climate risks are never Black Swans, really. Yet, the lack of pre-emptive management that comes with that mis-perception—a result of limited resources, cognitive biases, and short term political and economic incentives—has lasting consequences.

Abbots Langley, United Kingdom. © Lawrence Walters

In the UK, a country (mistakenly) associated with too much rainfall, we’ve seen a prolonged summer heatwave. To the dismay of a garden-loving people, hosepipe bans are being imposed in the usually wet northwest of England, while utilities are asking to extract more water from the country’s world-famous Lake District, a UNESCO World Heritage Site. Meanwhile, on the other side of the Northern Hemisphere, Japan, already struck by devastating floods, is reeling from a crippling heatwave that has killed at least 44 people since July 9th, with 11 dying on Saturday alone. Just a few short months ago, Cape Town was on the verge of collapse, as the approach of “day zero” marked the exhaustion of the city’s water supply in the face of drought, a predicament that São Paulo was in only three years ago: both were saved in extremis by winter rains. What all these events have in common is not just how extraordinary they are in the portrayal that is made to the public, but how all these societies choose to manage them in a regime of emergency.

Is it time to talk of the evolution of climate events as a Grey Rhino, rather than as an ever-growing sequence of Black Swans?

The choice to manage those risks ex-post rather than intervene ex-ante shapes public perception and creates the conditions for the next step in the dance between a difficult environment and the investments society makes.

In contrast to the notion of Black Swans, U.S. strategy expert Michele Wucker has introduced the idea of the ‘Grey Rhino’ to describe events that are actually staring us in the face, entirely expected, yet persistently ignored by a society in the throes of denial until it is too late. Wucker’s insight is not so much about the nature of these events, as it is about how society responds, or should respond, to them. Is it time to talk of the evolution of climate events as a Grey Rhino, rather than as an ever-growing sequence of Black Swans?

Consider the tragic floods that have hit Japan only a few weeks ago. Every time I visit this country, I cannot help but marvel at how much the landscape reflects a purposeful, meticulous approach to the management of water. It is inevitable: Japan is not gifted with particularly favorable hydrology. It has had to work hard to tame its environment and the enormously variable climate it must contend with.

Rainfall in Tokyo averages nearly 1.5m per annum—more than twice that of London. Not only does Japan receive more rain, but it often arrives in more concentrated bursts, including typhoons and monsoons.

Then there is topography. Japan is mountainous: roughly seventy percent of the country is on an incline, which means that the Japanese have had to adapt to using a lot of marginal land. It also means that rivers are short, steep, and, at least historically, shallow. Before modern engineering, most Japanese rivers were prone to frequent flooding and largely used to float logs downhill. With few exceptions, navigation and flood control came with modernization at the end of the nineteenth century, and at great expense.

It should therefore not come as a surprise that Japan is adapted to confronting difficult water events. The risks are too high not to manage them, and the country is too wealthy not to do something about it. And so decades of investments have left rivers heavily engineered to manage their waters and avoid impacts of floods, reclaiming land and protecting communities.

Rainfall in Tokyo averages nearly 1.5m per annum—more than twice that of London. Not only does Japan receive more rain, but it often arrives in more concentrated bursts, including typhoons and monsoons.

The country has also learnt how to learn from failure, a critical trait of a resilient society. For countries whose landscape is as heavily constructed and managed as is that of Japan, every disaster is a tail event: an unusual occurrence that represents an extreme of what ought to normally occur. Only the most exceptional circumstances make it through the various lines of defense that have been prepared by this ever-cautious society. But because of this, in those rare instances when those events do occur, society learns and adapts.

This is why we might be justified in considering the events in Japan a black swan, an event of such extremity to defy predictability. After all, they were truly exceptional in a meteorological sense: the coincidence of a typhoon and of a front coming in from the west, heavy with water, created a perfect storm that unleashed more rain, between July 3 and July 8, than the Japan Meteorological Agency had ever seen on record. In that sense it indeed exceeded the realm of experience.

But in another sense they represent a symptom of a wholly expected and rather predictable problem: the accelerating pace of modern society’s race to engineer itself out of suffering the consequences of an increasingly variable weather. According to the Japan Meteorological Agency, there has been a thirty percent increase in the occurrence of rainfall measuring more than two inches an hour, and a seventy percent increase in rainfall of more than three inches an hour. So are the events of Japan a climatic grey rhino, angrily staring at us and ready to charge?

There used to be an intergenerational cycle to the management of tail events. By construction these were typically secular: “hundred year floods” which most river infrastructure would be built to manage. Rivers would flood, leaving a wake of tragic destruction, which would prompt the construction of defenses that would protect communities for a generation or more, and in any case long after contemporary politicians were gone.

Over time, this protection would lull society into a false sense of security, the risks forgotten or underestimated, pushing people to move in closer to danger, increasing the value at stake for the next event, however unlikely. The next event, as inevitable as unpredictable, would then trigger further engineering and management, pushing the dance between society and nature on, a dance between failure and security, that over time shapes the landscape and the way in which society inhabits it.

But if the frequency of failures changes, if extreme events become more common, if the tail fattens, if catastrophe becomes an intra-generational rather than an intergenerational event, and if our ability to manage those events is tested beyond the limit, at some point we need to ask ourselves whether we need a different strategy.

© Jeremy Bishop

Japan is rich. Since 2013, its economy has consistently outperformed those of its G7 counterparts. It has the resources to bounce back and can absorb the shocks of catastrophic disasters. After all, as tragic as they were, the events of July pale in comparison to those of March 11, 2011, when a huge tsunami killed over 15,000. In response to these events, the country has consistently shown itself resilient, proving that recovery from disasters is a matter of discipline, resources and skill. The UK has faced drought before and it will manage this time too. Cape Town, São Paulo and the countless other cities around the world will face water risks and find ways to adapt or absorb the consequences. Or they will simply get lucky.

But at some point, as the frequency of these events increases, as the consequences of failure stay with the public memory enough to shape their expectations, treating these events as Black Swans, providing ex-post management in a regime of emergency, will prove an inadequate response. There will come a point when adaptation intended as continuous improvement in managing tail events will no longer be able to keep up with the perception of change. Then, societies will need a new strategy, and it will likely be expensive and will force us to ask difficult questions about the risks we are willing to avoid, and those that we are willing to take. But it will be a necessary evolution: a strategy not for Black Swans, but for Grey Rhinos.

Giulio Boccaletti, Ph.D., is the Chief Strategy Officer at The Nature Conservancy. Trained as a physicist and atmospheric scientist, Giulio is an expert on environmental and economic sustainability. In his role as Chief Strategy Officer, Giulio works to develop the organization’s strategy and apply economic and scientific practice to its conservation agenda.

Protect. Transform. Inspire. The Nature Conservancy is uniquely positioned to be a leader in taking on the most complex challenges facing the planet. Our place-based projects in over 40 countries serve as living laboratories where new ideas to protect nature are tested, perfected and adapted for other places. We engage businesses, governments and communities in delivering these on-the-ground results – demonstrating how conservation innovations can transform how our food, water and energy are produced. And by empowering more leaders and communities all over the world with solutions that work, we will inspire action at the scale of the challenge.

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