Placing water into the picture for climate change

In the United Nations Framework Convention on Climate Change negotiations in Copenhagen and Cancun, both mitigation (preventing climate change) and adaptation (responding to the increased risks of climate change) measures were on the table, but there was little mention of water. There is an understandable desire to focus on the core task of reducing greenhouse gases, but this must not be at the expense of ignoring the changes in water availability and quality that will accompany climate change. For the majority of people in the world, especially the poorest, water remains the most significant environmental and public health problem.

The lack of consideration of improved water provision as a way of reducing greenhouse gas emissions is understandable since the use of water usually accounts for only a few percent of the carbon footprint of most nations. There are exceptions to this rule; for example, for some countries in the Middle East treating and pumping water contribute as much as 30% of their energy use. But overall, a focus on water is not an effective way to get at mitigation.

For adaptation, the situation is starkly different. Water is arguably the most significant problem facing nations as a result of climate change; even if climate change were not occur, it is a global challenge to provide safe, plentiful, reliable and affordable water, especially as populations grow towards 9 billion. Sea level rise will affect communities world-wide, with some of the most dramatic effects being seen in the Lesser Developed Countries and Small Island Developing States that are the focus of international climate change efforts. Changing patterns of rainfall will bring increased drought or flooding to even the developed nations, with impacts on sustainable development and food security. Potential changes in the amount and quality of water are therefore at the heart of adaptation strategies, and leaving them off the table is a missed opportunity.

The world needs an aggressive international campaign of water-related adaptation measures, allocating resources where the risks are highest. This requires significant improvements in understanding how climate change risks will appear over time, and what management strategies can reduce these risks in the most cost effective, appropriate and equitable ways. This in turn requires improving the evidence base through advanced research such as that carried at the University of Cambridge in regard to:

• Supporting the scientific capacity to quickly identify storms that will bring flooding, and to evacuate effectively
• Protecting the processes of wastewater treatment so extreme weather events aren’t followed by outbreaks of microbial disease
• Developing drought-resistant crops
• Enhancing the ability of land to capture and store water, both to prevent flooding and to reduce evaporation back to the atmosphere
• Developing public health systems capable of identifying water-borne disease outbreaks in their early stages, and provide adequate health care
• Identifying strategies of sea wall defenses, and perhaps relocation, for communities in coastal regions affected by sea level rise
• Strengthening planning regulations to prevent further development in areas vulnerable to flooding and inundation by the sea

All of these are adaptation strategies that reduce the risks from climate change, and do so through a focus on water and its changing availability.

International negotiations hopefully will produce a framework for reducing the risk of climate change in the face of significant uncertainties as to timing and extent of that risk. A large part of the solution will be rapid and significant reduction in global emissions of greenhouse gases, and so that issue should be given pride of place in negotiations. This cannot, however, be at the expense of ignoring the central role of water in risk reduction. It is often said that mitigation is about air, adaptation is about water. The scientific, technological, behavioural, organisational and political innovations to produce effective adaptation strategies focused on water need international support, backed by a sound base of evidence that will ensure we tackle the right problems in the appropriate places with appropriate technologies and policies. That is a grand challenge for researchers in the 21^st century.

Dr Douglas Crawford-Brown is Executive Director, Cambridge Centre for Climate Change Mitigation Research, based within the Department of Land Economy, University of Cambridge.