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Realities of risk


We should focus on dangers that we can control, and particularly on those of our own creation.

When policy-makers consider global risks, they tend to extrapolate from headlines. Troubles in the eurozone could spiral out of control, conflict in Syria could spark wider unrest, the H5N1 bird-flu virus could mutate and spread from person to person in a global pandemic. Those dangers and many others are clear and present; society is well-advised to prepare for them, and takes good advice on how to do so. The World Economic Forum (WEF), for one, publishes an annual risk-assessment report.

There is, however, another category of risk: the unheralded dangers that sneak up on us. Many are the unforeseen consequences of progress, of humanity’s scientific and technological quests. For its 2013 report, the WEF asked the editors and journalists of Nature to identify five of the most disruptive of these risks, dubbed ‘X factors’.

Neuroscientists, for instance, are avidly pursuing drugs and devices that could deliver real cognitive enhancement — not just sharpening our alertness and ability to focus, as certain drugs already do, but upping our intellectual firepower. From students to business executives, the demand for such drugs would be huge — and so would the potential for an X factor to strike. Few drugs affect just a single target. The neurotransmitter systems important to cognition also serve other functions, raising the spectre of serious side effects: for example, a drug that boosts memory might also make the user more prone to impulsive behaviour. And then there are the ethical conundrums: should the market decide who gets the benefits of these drugs and who does not? Should they be banned, to level the playing field — or subsidized, for the same reason?

Climatologists have more mixed feelings about schemes for geoengineering — deliberately altering the climate system to combat the effects of rising greenhouse-gas emissions. In one scenario, high-flying jets or balloons would release a haze of sulphate particles into the stratosphere, dimming the Sun’s rays and cooling the planet. Fearful that geoengineering could affect the climate system in unexpected ways, researchers have deliberated and studied it, and so far proposed only the most cautious of experiments. A second X factor looms here: geoengineering is simple and cheap enough that a rogue nation, or even a company, could deploy it on a large scale before its risks are well understood, perhaps triggering a widespread climatic crisis.

The other X factors that Nature staff identified are no less dramatic: the societal burden of the millions of people who, thanks to progress against killer diseases, will join the ranks of the disabled and those with dementia; catastrophic climate feedback such as the collapse of an ice sheet; and the possible social consequences of contact with alien life (although this is perhaps more X-files than X factor).

In this week’s issue, Nature also takes up related topics. A World View on page 135 offers psychological insight into ‘digital wildfires’ (a danger explored in Global Risks 2013). These are a much more certain danger than the X factors — in fact, they are a regular feature of the Internet, flaring up practically by the minute as rumours or personal attacks race through cyberspace. Meanwhile, a Comment on page 157 examines the shortcomings of efforts to forecast state changes such as the collapse of ecosystems or the outbreak of epidemics.

Finally, a Feature on page 154 offers the liberating perspective that some of the very worst things that could happen — catastrophes that could devastate the biosphere, and human society with it — are out of our hands. These strokes of cosmic bad luck, among them supervolcanoes, apocalyptic tsunamis driven by undersea landslides, and mega solar flares, have all happened in the geological past and are sure to strike again someday. But in many cases there is little we can do to prepare or stave them off — and so there is no point in worrying.

Related links

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Tipping points: From patterns to predictions 2013-Jan-09

Rumour research can douse digital wildfires 2013-Jan-08

Planetary disasters: It could happen one night 2013-Jan-08

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Global Risks

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Realities of risk. Nature 493, 134 (2013).

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