“The evidence shows that climate change is occurring ...and we cannot wait any longer to take action,” declared UN Secretary-General Kofi Annan in a speech to American college students back in May 2001. Almost every day, it seems that we hear further evidence that the Earth's climate is changing. The 1990s was the warmest decade in the last hundred years, and 1998 was the warmest year on record. During the past century, global temperatures climbed by about 0.5°C – the largest increase in at least one thousand years.1 As a result, snow cover is decreasing, glaciers are retreating, lakes and rivers are warming, rainfall patterns are changing and El Niño episodes are occurring more often. Extreme weather, including thunderstorms, flash floods, and droughts, are becoming more frequent and severe in many areas of the world. The diminishing Arctic sea-ice and rising sea levels further contribute to global distress. These changes are causing biological systems to alter, affecting the range, distribution and population density of a multitude of plants and animals around the globe. Whether the topic is polar bears or poplar trees, there is now compelling evidence of a world that is starting to warm up.
For many water professionals, however, the onset of a warming world is not considered a real problem. Many of the public debates on climate change have left the impression that the science is unclear and that the causes and effects of climate change are still in doubt. In addition, there have been few serious attempts to inform water experts about the links between climate change and the water sector. Under such circumstances, it is hardly surprising that the water sector has so far paid little attention to climate change, preferring for the most part to focus on other issues that must seem far more pressing. Although quite understandable, continuing to ignore or underestimate climate change and its impact on the water sector would be a mistake.
In the first place, the science of climate change is now anything but unclear about what direction we are heading. While models might differ in projecting the rate and magnitude of warming, all of them project a warming of the Earth's climate, and all forecast significant changes in water quantity and quality and in the ecological character of ecosystems around the world. Though there are still some processes such as the role of clouds and water vapour that vex climate experts, the last fifteen years of research and modelling has revealed a great deal about how the climate system operates and the key factors that drive it to change. The original trickle of evidence has now become a flood.Further, though a small number of scientists contest the conclusions of climate change research, the vast majority agree that the Earth's climate is changing and that much of the change can be attributed to human activities.2,1
“THE ORIGINAL TRICKLE OF EVIDENCE HAS NOW BECOME A FLOOD.”
“So climate change is a problem, but it is probably not an urgent one” might be the reply of a sceptical water professional. He/she would point out, quite correctly, that the most dramatic warming to the Earth's climate is expected to take place in 50 to 100 years time, so there is no real need to address this problem now. “With so many other more pressing and more localized water management issues to deal with today - connecting people to clean water and maintaining irrigation, for example - why should I divert attention to what is perceived as a long-term problem?” the cautious water professional could ask.
But, the recurring droughts in South Asia and throughout Africa, the recent floods in Europe, Mozambique, Bangladesh, Vietnam, and Hurricane Mitch in Central America and Hurricane Andrew in the United States are continuing reminders of societies' vulnerability to climatic events. These events shatter lives and cripple economies. In the worst cases, whole societies are set back developmentally for a decade or more. Though these individual events cannot be directly attributed to climate change, they foreshadow the changes that are on the horizon.
Many of the decisions water professionals make today can reinforce societies' vulnerability if climate change is not taken into account. Over-exploiting rivers and wells for irrigation can exacerbate sensitivities to drought, for instance. Our decisions today will greatly affect society's ability to adapt to increasing variability in tomorrow's climate. Climate change is, therefore, not an issue that can be left for 50 or even 20 years, but one that needs to be addressed now.
What should water professionals be doing to respond to the problem? The more sceptical water professional might give a conservative answer: “The existing technologies and approaches will be sufficient to cope with the problem, just as they have in the past. We can construct more dams to store water and build more irrigation canals to re-distribute water resources.” According to this approach, dealing with climate change will require nothing more than a quick technological fix; indeed, it provides a further reason to continue with conventional sector-oriented water resources management.
But, using traditional measures is unlikely to help. Indeed, those who rely on the “tried and true” approaches of the past could land themselves in hot water. That's because climate change challenges existing practices by adding a critical new element to the equation: uncertainty. The historic basis for designing and operating infrastructure no longer holds with climate change because the future hydrological regime cannot be assumed to be the same as that of the past. The key challenge, therefore, is incorporating uncertainty into water resources planning and management.
“THOSE WHO RELY ON THE ‘TRIED AND TRUE’ APPROACHES OF THE PAST COULD LAND THEMSELVES IN HOT WATER.”
If there is no easy fix for climate change, then whose responsibility is it to deal with the problem? Some water professionals would prefer to believe that it is not theirs. After all, it is the energy-consuming sectors of the economy that have created this problem. Should it not also be their responsibility to fix it by reducing the amount of carbon dioxide and other greenhouse gas emissions generated by the use of coal, oil, and gas ?
Unfortunately, it isn't that easy. Although governments and some progressive businesses are starting to take responsibility for their emissions, we are now past the point where the current warming of the Earth can be avoided. Worse still, the emissions reductions that have been agreed so far are too modest to have any significant impact on the warming trend. Most experts regard the Kyoto Protocol as "a first step".
For better or worse, climate change is certain to become a growing pre-occupation of water professionals around the world. Increasingly, water resources management is about reconciling different and changing water uses and demands. Conventional water resources management has been shown to have its weaknesses by being too inflexible to address the current challenges facing the sector. In this respect, adaptation to climate change can be viewed as an opportunity to reinforce the trend towards greater flexibility in the way water use is managed and planned. It can be a positive force that strengthens existing and new efforts to innovate water management. As such, even the most sceptical water professional would be well advised to learn more about successfully adapting to climate change.
Snow and ice cover on Mount Kilimanjaro in 1993
Snow and ice cover on Mount Kilimanjaro in 2000