It is close to 20 years since the Earth Summit in Rio and 17 years since the United Nations Framework Convention on Climate Change (UNFCCC) came into force in 1994. Thirteen years have passed since the Third Conference of Parties to UNFCCC (COP3) in Kyoto where, for the first time, a framework for defining emission targets was discussed. Each year increasing numbers of delegates participate in the UNFCCC COP meetings as well as the media and activists. But I have begun to wonder what we have achieved. Have we really done anything concrete? Perhaps not. There are many reasons for this and it is beyond the scope of this piece to discuss them all, so I will limit myself to one important reason –– uncertainty.

While large strides have been made in climate science, there is still significant uncertainty about how the climate will evolve in the future. This uncertainty increases if you use the climate projections for impact assessment. Uncertainty is one of the key reasons for inaction. Unfortunately, uncertainty is part of scientific reality. Scientists are often blamed for their ‘grey’ information, while the media or a person with non-scientific training wants it to be black and white. Future prediction is a probabilistic approach and uncertainty is inherent. A person with a non-scientific background wants to know whether glaciers in the Himalayas will disappear in 30 years or not. This might be a very interesting piece of information for the media, but what is its value for decision making? It is more important to project the future evolution of glaciers with known uncertainty than to make glossy overstatements without any hint of doubt.

We insure our houses, even though we don’t know whether a disaster will ever strike, or if it does, when. We take an umbrella, just in case it might rain. We know there is uncertainty in the weather prediction, but still we take precautions. So why doesn’t it work for climate change? Yes there is uncertainty, but surely if there is any likelihood we should be prepared? A key question that everyone who is concerned by climate change issues should ask, particularly those who are sceptical, is how large does the probability of serious climate change have to be before we should start taking real abatement measures?

I think the responsibility lies largely with the scientists to honestly explain the fact that handling uncertainty and trying to reduce uncertainty is key to the scientific method. It is scientists’ duty to convey that unlike driving a car where you apply the brakes and the car stops, in the case of climate change, you apply the brakes today and the car will slow down only decades later and may come to a stop much later still. Inaction is certain to increase the braking distance. By- Arun B. Shrestha, ICIMOD Nepal