Dealing with uncertainty
How can we decide what to do when the future is unclear?
It is now widely accepted that climate change is happening and will affect human health. But does that mean something needs to be done? Some form of risk analysis can be tried, which would aim to answer questions such as:
- What is the likelihood that something will happen?
- What would be its impact?
- What are the options for preventing it?
- How effective are these approaches likely to be?
- What side-effects might they have?
Unfortunately, none of these questions is easy to answer. The Intergovernmental Panel on Climate Change (IPCC) has undertaken a heroic effort to gather evidence, and acknowledges various degrees of uncertainty in its predictions.
The 2014 IPCC report stresses that although the body of evidence about climate change has grown “tremendously”, it still cannot predict conditions with 100 per cent certainty.
Many now believe that the likelihood of serious impacts, including effects on health, is so high that urgent action is essential. Yet these actions are not without cost – reducing carbon emissions, for example, will impose an economic cost. So others argue that we should hold fire.
Some governments are beginning to take action. The EU, for example, now has targets to reduce carbon emissions by 2050 by 80–95 per cent compared to 1990 levels.
Yet emissions also need to be reduced in the rapidly industrialising countries of the developing world. The so-called BRIC countries (Brazil, Russia, India and China) may hold the key. Encouragingly, the Chinese government looks to be taking the issue seriously.
And by lowering rates of deforestation in its tropical rainforests, Brazil has done more than any other country to reduce carbon emissions, according to one recent study.Lead image:
Ben Britten/Flickr CC BY