Climate change can reasonably be expected to increase the frequency and intensity of a variety of potentially disruptive environmental events-slowly at first, but then more quickly. It is prudent to expect to be surprised by the way in which these events may cascade, or have far-reaching effects. During the coming decade, certain climate-related events will produce consequences that exceed the capacity of the affected societies or global systems to manage; these may have global security implications. Although focused on events outside the United States, Climate and Social Stress: Implications for Security Analysis recommends a range of research and policy actions to create a whole-of-government approach to increasing understanding of complex and contingent connections between climate and security, and to inform choices about adapting to and reducing vulnerability to climate change.

The book is an attempt to address the important facts and figures relating to climate change impacts on water security: a. Climate change impacts on water resources; b. Climate change impacts on water related diseases; c. Climate change impacts on water dependent biodiversity and ecosystems; d. Climate change adaptation and mitigation measures for water security; and e. Climate change and greenhouse gas emissions from water sector. • Climate change is an additional stress on water security in addition to other chemical and biological stressors. • Rivers depending on the Himalayan glaciers (the Indus, Ganges, Brahmaputra) could face water shortages or reduced river run-off due to retreat of glaciers, and this would cause dramatic impact on drinking water supplies, biodiversity, hydropower generation, industry, agriculture, ecosystems on which about 2.4 billion people in Asia depends. • As a consequence of drought, the annual stream flow in the Murray-Darling basin (Australia) is projected to fall by 10-25% by 2050 and 16-48% by 2100 which would have severe consequences on irrigated agriculture in the region. • Rise of water temperatures may enhance proliferation of harmful algae (some of algae produce toxins), causing water quality problems for recreational activities, fisheries/fish farming, irrigation, and drinking and seafood contamination with algal toxins. • Global warming is projected to increase river water temperatures in a number of countries including the USA (the Mississippi, Colorado, and Mackenzie basins), Europe (the Rhine, Danube, and Rhone basins), eastern China (the Yangtze), and Australia (the Murray-Darling). • Sea-level rise (SLR) will cause salinization of coastal groundwater resources, and may damage or destroy many coastal ecosystems including wetlands, salt marshes, and may cause saline water intrusion in agriculture and freshwater aquaculture facilities, a shift in community composition of mangrove forests, etc. • It is projected that a 1°C rise of temperature in the future can increase the initial relative risks of cholera by 15 to 29 percent. Both rise of temperature and sea-level may enhance dengue and malaria. • To adapt to climate change, we need increasing storage capacity, rainwater harvesting, improvement of water use efficiency, desalination of seawater, water savings, mandatory rainwater tanks in new and old buildings, use of recycled/reclaimed water, virtual water trade, improvements in irrigation efficiency, modification of irrigation techniques, reducing leakage of irrigation pipes, selection of climate resilient crops to save scarcity of water resources. • Water processes (abstraction, treatment, end use and wastewater treatment) do emit Greenhouse gases (GHG). In irrigation, pumping of water is the most energy-demanding process and consequently causes more GHG emissions (CO2). Dams/reservoirs emit GHGs such as methane. • The most effective way to decrease carbon footprint in water sectors is to use low carbon emitting fuels such as, renewable energy (solar, wind or nuclear). Ecological toilet may be promoted to reduce GHG emissions from septic tanks in developing countries. • Stopping or slowing deforestation, forest degradation and sustainable management of forests may significantly contribute to avoid GHG emissions, may conserve water resources and prevent flooding, reduce run-off, control erosion, reduce siltation of rivers, and protect fisheries and preserve biodiversity. • Mangrove ecosystems can play an important role in the protection of the coast from the natural disasters (cyclones, tsunamis) and could act as a barrier (live seawalls) against disasters and help minimize damage to property and life.

In Asia and the Pacific, climate change is now a well-recognised risk to water security but responses to this risk are either under reported, or continue to be guided by the incremental or business as usual approaches. Water policy still tends to remain too narrow and fragmented, compared to the multi-sectoral and cross-scalar nature of risks to water security. What’s more, current water security debates tend to be framed in discipline specific or academic ways, failing to understand decision making and problem-solving contexts within which policy actors and partitioners have to operate on a daily basis. Much of the efforts to date has focussed on assessing and predicting the risks in the context of increasing levels of uncertainty. There is still limited analysis of emerging practices of risks assessment and mitigation in different contexts in Asia and the Pacific. Going beyond the national scales and focussing on several socio-ecological zones, this book captures stories written by engaged scholars on recent attempts to develop cross-sectoral and cross-scaler solutions to assess and mitigate risks to water security across Asia and the Pacific. Identifying lessons from successes and failures, it highlights management and strategic lessons that water and climate leaders of Asia and the Pacific need to consider. This book showcases reflective and analytical thought pieces written by key actors in the climate and water spaces. Several critical socio-ecological zones are covered – from Pakistan in the west to pacific islands in the east. The chapters clearly identify strategies for improvement based on the analysis of emerging responses to climate risks to water security and gaps in current practices. The book will include an editorial introduction and a final synthesis chapter to ensure clear articulation of common themes and to highlight the overall messages of the book.

National and global security can be assessed in many ways but one underlying factor for all humanity is access to reliable sources of water for drinking, sanitation, food production and manufacturing industry. In many parts of the world, population growth and an escalating demand for water already threaten the sustainable management of available water supplies. Global warming, climate change and rising sea level are expected to intensify the resource sustainability issue in many water-stressed regions of the world by reducing the annual supply of renewable fresh water and promoting the intrusion of saline water into aquifers along sea coasts, where 50% of the global population reside. Pro-active resource management decisions are required, but such efforts would be futile unless reliable predictions can be made about the impact of the changing global conditions on the water cycle and the quality and availability of critical water reserves. Addressing this wide spectrum of issues, a team of expert authors discusses here the impacts of climate change on the global water resources, the long-term resource management goals at global and local scales, the data requirements and the scientific and technical advances necessary to mitigate the associated impacts.

Confronting Climate Uncertainty in Water Resources Planning and Project Design describes an approach to facing two fundamental and unavoidable issues brought about by climate change uncertainty in water resources planning and project design. The first is a risk assessment problem. The second relates to risk management. This book provides background on the risks relevant in water systems planning, the different approaches to scenario definition in water system planning, and an introduction to the decision-scaling methodology upon which the decision tree is based. The decision tree is described as a scientifically defensible, repeatable, direct and clear method for demonstrating the robustness of a project to climate change. While applicable to all water resources projects, it allocates effort to projects in a way that is consistent with their potential sensitivity to climate risk. The process was designed to be hierarchical, with different stages or phases of analysis triggered based on the findings of the previous phase. An application example is provided followed by a descriptions of some of the tools available for decision making under uncertainty and methods available for climate risk management. The tool was designed for the World Bank but can be applicable in other scenarios where similar challenges arise.