Robust Response to Climate Change Risk and Uncertainty

Australia needs a robust response to climate change that explicitly recognises risk and uncertainty to make us more resilient to the range of possible future situations. Coverage of the Australian Climate Commission’s science update, The Critical Decade, and an interim report into Public Risk Perceptions, Understandings, and Responses to Climate Change in Australia and Great Britain have made it clear that this issue is still not fully understood.

Doing nothing in response to climate change exposes us to uncertainty: it is betting that what we currently have is able to cope with whatever the future throws at us. Like choosing clothes for a week-long trip based on today’s weather, it may work – but it would make more sense to prepare by a) finding out what the weather is forecast to be; and b) packing clothes that can adapt to all sorts of weather, in case the predictions are wrong. (Melburnians know all about this.)

Uncertainty should be distinguished from risk: risk is the combination of the likelihood of an (unwanted) event occurring and the severity of its consequences. Where the likelihood or severity are not precisely known, the predictions can be expressed in terms of probabilities; when the Climate Commission talks about “1-in-100 year events” (such as floods), they are describing risk, just as a meteorologist’s “chance of rain” describes risk.

Uncertainty is when we don’t know the risks; when we don’t know how probable an event is. (Some would argue that this describes meteorologists, but let’s be kind.) When opponents of action against climate change argue that there is “uncertainty around climate change”, they are technically correct – but it’s not that we don’t know that it’s going to get worse; we just don’t know how much worse it’s going to get.

An example is the Climate Commission’s projection of global average sea-level rises of 0.5 to 1.0 metre in 2100 compared to 1990, which would result in an increased frequency (higher risk) of high sea-level events (floods) in coastal areas. The Commission openly admits that uncertainty surrounds this figure, but that simply means we do not currently know which areas will have five, which will have ten, and which will have 100 times as many high-sea level events, not that this increase won’t occur.

If I belabour this point, it is because 56% of Australians recently surveyed by Griffith University and Cardiff University about their risk perceptions agree that the effects of climate change are uncertain, and 42% are unsure about or disagree with the notion of scientific consensus on climate change. (Source (PDF), Appendix Questions 12i, 12j, 28)  As The Critical Decade points out (PDF):

• On a timescale of multiple decades to centuries, the Earth is warming, and at a very fast rate by geological standards. There is no doubt about this statement.
• Human emissions of greenhouse gases are the primary factor triggering observed climate change since at least the mid 20th century. The IPCC attached 90% certainty to that statement in 2007; research over the past few years has strengthened our confidence in this statement even more.
• Many uncertainties surround projections of the particular risks that climate change poses for human societies and natural and managed ecosystems, however, the number and magnitude of climate risks will rise as the climate warms further.

More positively, the Griffith/Cardiff University study (PDF) found that 71% of Australian respondents were personally convinced that climate change is really happening”; 90% believed that human activities were playing a causal role in climate change; 66% reported that they were “very concerned” or “fairly concerned” about climate change; and less than 6% of respondents could be characterised as being disbelievers or strong sceptics with respect to the reality of current climate change and/or the causal role of human activities and environmental impacts.

So what to do? When you know what the future will be (or can accurately predict it), taking a “big bet” of action or inaction will bring the biggest payoff – but only if the bet is correct. Under uncertainty, a robust strategy is better: one that has an acceptable outcome regardless of what happens by hedging against possible futures (even if that outcome isn’t as good as if we’d guessed correctly). Robust strategy is generally adaptable, and involves building the capability (technological, political, and institutional) to recognise the signs that we need to react and to do so quickly. 

The Australian Defence Force (ADF) is an example of robust policy: though we have no certainty about the location, timing, or nature of future conflicts, the ADF maintains a range of units and institutions with different capabilities to be able to respond quickly with whatever strategy is most appropriate. The wait-and-see approach, on the other hand, is more akin to New South Wales’ action on infrastructure, where little is done until the system is at breaking point and fixing it will take years.

The suggested course of (in)action – business as usual – from those who claim there is doubt about climate change is thus at odds with sensible management of risk and uncertainty. When you’re uncertain, you prepare by hedging your bets, not by taking a punt on the non-occurrence of catastrophe.

The more certain we are that dangerous climate change is occurring – and The Critical Decade is more certain than any report before it –, the more we should invest in anticipatory measures such as emissions reduction or adaptive measures to cope with the foreseen changes. The less certain we are, the more we should explore reactive measures that allow us to improve our level of knowledge (e.g. through environmental science) and act quickly once we have become certain (e.g. through environmental technologies, similar to those encouraged by the innovation programs scrapped a few months ago by the Gillard Government). But doing little or nothing about climate change is a course we should take only if we are completely certain that climate change is NOT occurring. And less than 6% of Australians believe that.

Regardless of your view on the correct level of a carbon price, having an appropriate emissions trading scheme gives us the crucial capability to control emissions, should we need to. Effective technological and innovation policy can give the capability to reduce or even reverse CO₂e emissions, should we need to, and a sensible combination of an ETS, technology programs, and other policies will be more robust than any of these alone. Given the time lags inherent in the climate system, reducing our scientific, technological, political, and institutional response times is especially valuable; so, too, is the “learning-by-doing” effect. These strategies benefit us simply by protecting us against uncertainty, even if the worst-case scenarios don’t come to pass – and especially if they do.

Both proponents and sceptics view the risks and uncertainties involved in climate change with concern. Let’s deal with that uncertainty by implementing robust policies to secure Australia’s future under all foreseeable eventualities.

This post was first published on New Matilda.