Effects of climate change on fresh water resources

There is abundant evidence that freshwater resources will be affected by climate change, and concern that these impacts will harm societies and ecosystems, and subsequently social and economic development (Bates et al., 2008; Calow et al., 2011; UN Water, n. d.). Observed and projected impacts will increase food insecurity and vulnerability among people living in arid and semi-arid areas in particular (Bates et al., 2008). Populations whose livelihoods depend on water ecosystems, such as fishing communities, will face growing challenges (see Coastal zones below). Higher and fluctuating temperatures are likely to reduce water quality (Bates et al., 2008; Calow et al., 2011), which will affect human health and ecosystems, and will probably lead to an increase in water-borne disease (Calow et al., 2011). Economic implications will include higher costs for existing water infrastructure and management practices such as flood defences, and irrigation and sanitation systems (Bates et al., 2008; Mogaka et al., 2006; FAO, 2013, Module 3).

Water scarcity may also worsen the existing stresses of population growth and urbanisation (Bates et al., 2008; Calow et al., 2011). Questions of equity and access therefore become critical issues (Calow et al., 2008). For example, for women and girls, water scarcity means having to spend more time and travel further to collect water, which reduces their productive work and economic opportunities (IFAD, 2007). Accordingly, some experts emphasise the importance of recognising resource access and entitlement issues in designing climate change adaption and mitigation measures.

Bates, B. C., Kundzewicz, Z. W., Wu, S., & Palutikof, J. P. (Eds.). (2008). Climate change and water. Technical paper of the Intergovernmental Panel on Climate Change. Geneva: IPCC Secretariat.
Observational records and climate projections provide abundant evidence that freshwater resources are vulnerable and may be significantly affected by climate change. Such impacts will have wide-ranging consequences for societies and ecosystems. This paper presents an overview of IPCC research on water, highlighting the strong likelihood of increased variability and extremes, areas of uncertainty, and regionally-differentiated impacts. Negative impacts of climate change on freshwater systems are expected to outweigh the benefits. Adaptation strategies need to integrate demand- and supply-side action, designed in the context of wider development, environment and health policies.

Mogaka, H., Gichere, S., Davis, R., & Hirji, R. (2006). Climate variability and water resources degradation in Kenya: Improving water resources development and management (World Bank Working Paper No. 69). Washington, DC: World Bank.
This report focuses on the economic implications of water resource management in Kenya (and Africa more widely), highlighting the effects of climate variability and the steady degradation of water resources. Both processes have significant economic impacts over the long term. Increased investment in infrastructure and better management of water resources are advocated to reduce costs.

Calow, R., Bonsor, H., Jones, L., O’Meally, S., MacDonald, A., & Kaur, N. (2011). Climate change, water resources and WASH: A scoping study. London: ODI.
This report reviews the literature on current understanding of climate change projections and scenarios, and discusses the implications for water supply, sanitation and hygiene (WASH) in Sub-Saharan Africa (SSA) and South Asia. Water scarcity is not environmentally determined, but driven by questions of equity and access; demographic change will be a more important driver of water scarcity than climate change in SSA until at least 2050. Refocusing the debate on water security offers a way forward, emphasising the importance of resource access and entitlements as well as water availability.

IFAD. (2007). Gender and water. Securing water for improved rural livelihoods: The multiple-use system approach. Rome: IFAD.
How can women participate in water management? This review examines the impact of water-related projects on women, women’s role in managing water resources, and constraints women face in gaining access to water. Lessons in promoting women’s participation in decision-making from IFAD-supported water projects include: enhancing women’s access to financial services by allocating a minimum quota of loans for women; and enhancing women’s capacity through training in income-generation activities, irrigation methods, and water conservation. Approaches to mainstream gender in water management include gender-sensitive project design and targeting, sex-disaggregated data collection and analysis, gender-sensitive indicators, and gender-responsive budgets.

Mitigation and adaptation in the water sector

Experts suggest that water management practices should be made more robust by incorporating improved information systems about climate variability, adjusting and re-engineering systems, modifying demand, and introducing new technology (Bates et al., 2008; UN Water, n.d.; World Water Assessment Programme, 2009). Others urge donors to climate-screen WASH and resource management strategies and to climate-proof interventions, maximising climate change mainstreaming at different levels. They also advise giving project managers guidance on how to minimise risk (Calow et al., 2008; FAO, 2013, Module 3). Evidence suggests that effective mitigation to improve water-use efficiency requires both demand- and supply-side strategies, for example, using economic incentives through metering, combined with increased water storage (Bates et al., 2008).

Because climate change impacts on water affect many policy areas (e.g. health, energy, agriculture and livelihoods), experts recommend that adaptation and mitigation options should incorporate a wide spectrum of water-dependent sectors (Bates et al., 2008; FAO, 2013, Module 3). Experts also argue that water adaptation should be addressed within the broader development context, focusing on challenges for poverty reduction, hunger, disease and environmental degradation (UN Water, n.d.).

Lessons from community-level adaptation projects include: build on existing coping strategies; adopt wide-ranging communication strategies; harness local and national support; and include broad-based livelihood improvement (Calow et al., 2008). Women can play a central role in the provision, management and safeguarding of water in developing countries (IFAD, 2007).

World Water Assessment Programme. (2009). Water in a changing world. World water development report. UNESCO/Earthscan.
This report analyses the state of the world’s freshwater resources. Human activities have become primary drivers of the pressures affecting water systems. Important decisions affecting water management are made outside the water sector and are driven by external, largely unpredictable forces including demography, climate change, and technological innovation. Decision-making in other development sectors – such as food, energy, disaster management and climate change – should incorporate water as an integral component. Investment in improved water resource management can prevent losses from droughts and floods, and build resilience to climate variability.

UN Water. (n.d.). Climate change adaptation: The pivotal role of water. UN Water.
Water is the primary medium through which climate change influences ecosystems and societies. This policy brief notes that water stress is already high in many developing countries, and argues that adaptation must be addressed in a broad development context. Five broad approaches are outlined: new investment, adjusting existing practices, re-engineering existing systems, modifying demand, and introducing new technology. Countries are urged to improve their water resource management systems and implement ‘no regrets’ strategies ‒ measures that provide development benefits now, as well as strengthening resilience to climate change.