Section V Integration and Conclusions
Drought and Water Crises: Lessons Drawn, Some Lessons Learned, and the Road Ahead
By the middle of the 21st century more than half of the planet will be living in areas of water stress where supply cannot sustainably meet demand (The Economist, Nov. 5,2016).
Despite the fact that drought is an inevitable feature of climate for nearly all climatic regimes, progress on drought preparedness has been extremely slow. Historically, the approach taken by most nations has been reactive, responding to drought in a crisis management mode. Many nations now feel a growing sense of urgency to move forward with a more proactive, risk-based drought management approach (Wilhite 2000; Wilhite et al. 2014) as highlighted in Parts I and II of this book, Chapters 1 through 5, and in several of the case studies in Part IV. Certainly, the widespread occurrence of this insidious natural hazard in recent years has contributed to the sense of urgency. But, drought occurs in many parts of the world and affects portions of many countries, both developing and developed, on an annual basis. For example, the average area affected by severe and extreme drought in the United States each year is about 14 percent. This figure has been as high as 65 percent (1934 and 2012) and has hovered in the 35-40 percent range for most years since 2000. (Thus, global estimates of drought occurrence trends can mask significant regional and local changes.) So, does the widespread occurrence of drought in the United States over the last 10 years explain the emergence of several national and state initiatives centered on drought monitoring and preparedness, given that events of this magnitude have not motivated policy makers to act in the past? To some degree, we would say, yes. Widespread, severe, and multiyear droughts in other countries or regions in recent years (e.g., Australia, Brazil, the Greater Horn of Africa, and Mexico) have also been instrumental in moving the conversation on improving drought monitoring and preparedness forward. However, our experience would suggest that this is only one of the factors contributing to the increased attention to drought risk management in many drought-prone countries.
Climate change and the potential threat of an increase in frequency and severity of extreme events is also a contributing factor. In the first edition of this book, we concluded that climate change was probably not playing a significant role in this trend because most policymakers have difficulty thinking beyond their term of office or the next election, and many businesses were unwilling to look beyond their next quarterly report. At this writing, we suggest that it is now more likely that climate change is playing a significant role in driving decisions for countries, communities, and water managers to invest time and resources into drought risk management, specifically directed toward the development of more comprehensive drought monitoring, early warning and information systems, vulnerability assessments, preparedness planning, and national drought policies. This increased attention to improving drought management is likely because more countries are now experiencing noticeable changes in their climate along with an increase in the frequency and severity of drought. For regions that have experienced either a downward trend of annual precipitation or a higher frequency of drought events (perhaps multiyear in length), or both, the potential threat of climate change now seems more real. In addition, a series of activities and actions have also stimulated greater interest in and progress on drought risk management. For example, the convening of the High-level Meeting on National Drought Policy (HMNDP) in 2013 with 87 countries in attendance (see Chapter 2) and a number of follow-on activities to that conference (e.g., the launching of the Integrated Drought Management Programme [IDMP]— see Chapter 3), the regional workshops on building capacity for national drought policies, new initiatives in the EU (see Chapter 18), and the 2016 African drought conference (http://allafrica.com/stories/201608180693. html) have helped to spread the concepts and garner support for drought risk management and national drought policies.
Decision-making under uncertainty is onerous but unavoidable. Some policymakers and resource managers remain of the opinion that climate change projections are in error, preferring to presume that there will not be a change in the climate state and that extreme climatic events such as drought will not change in frequency or severity. Little consideration is given to the real possibility that projected changes in climate may be too conservative, or underestimate the degree of change in the frequency and severity of extreme events for some locations. In some areas, drying due to climate change is overlaid on the periodic droughts those areas have always experienced. As illustrated in this volume, the occurrence of extreme climate variability, including drought, coupled with high temperatures and other atmospheric factors and land surface conditions, can result in events that exceed climate model projections.
In addition to the factors mentioned above, it is our opinion that the growing interest in drought preparedness is also associated with the documented increase in social, economic, and environmental vulnerability, as exempli- tied by the increase in the magnitude and complexity of impacts. Although global figures for the trends in economic losses associated with drought do not exist, a report from the UN Development Programme (UNDP Bureau of Crisis Prevention and Recovery 2004) indicates that annual losses associated with natural disasters increased from US$75.5 billion in the 1960s to nearly US$660 billion in the 1990s. Losses resulting from drought likely follow a similar trend, but actual impacts, including economic loss numbers, are not well known. These figures for natural disasters, and especially drought, are likely significantly underestimated because of the inexact reporting or insufficiency of the data. Loss estimates do not include social and environmental costs over time and secondary and higher order impacts such as on hydropower. This increase has been observed in both developing and developed countries, although the types of impacts differ markedly in most cases, as illustrated by numerous authors in this book. Most estimates of drought- related losses exclude indirect losses—livelihoods, informal economies, intangible losses including ecosystem services, quality of life, and cultural impacts (Pulwarty and Verdin 2013).
With respect to drought, how can we define vulnerability? It is usually expressed as the degree of a society's capacity to anticipate, cope with, resist, or adapt to, and recover from the impact of a natural hazard. Capacity on paper does not always translate to capability on the ground. Urbanization is placing more pressure on limited water supplies and overwhelming the capacity of many water supply systems to deliver that water to users, including agriculture, especially during periods of peak demand. More sophisticated technology decreases our vulnerability to drought in some instances while increasing it in others. Greater awareness of our environmental and ecosystem services and the need to preserve and restore environmental quality is placing increased pressure on all of us to be better stewards of our physical and biological resources. Environmental degradation such as desertification is reducing the biological productivity of many landscapes and increasing vulnerability to drought events. All of these factors emphasize that our vulnerability to drought is dynamic and must be evaluated periodically. The recurrence of a drought today of equal or similar magnitude to one experienced several decades ago will likely follow different impact trajectories and result in far greater economic, social, and environmental losses and conflicts between water users.