Climate Change Adaptation World Meteorological Organization Working together in weather, climate and water WMO Climate Change Adaptation The Pivotal Role of Water AVINASH TYAGI Director, Water and Climate, WMO Coordinator: UN-WATER Thematic Priority Area Water and Climate Change WATER DAY 2 June 2010, Bonn, Germany Global Framework for Climate Services WMO: Climate and Water www.wmo.int

Potential Climate Change Impacts Global Framework for Climate Services

Weather, Climate and Water Severe Storms, Tropical Cyclones (Hurricanes and Typhoons), Storm Surges, Floods, Droughts, Cold Spells, Heat Waves, forest fires, locust swarms, etc… Global Framework for Climate Services

Effects on the hydrological cycle (IPCC 2001) Precipitations Evaporation Soil moisture Groundwater Water Demand Introduction The three key developments here are constructing scenarios that are suitable for hydrological impact assessments, developing and using realistic hydrological models, and understanding better the linkages and feedbacks between climate and hydrological systems. The heart of the scenario “problem” lies in the scale mismatch between global climate models (data generally provided on a monthly time step at a spatial resolution of several tens of thousands of square kilometers) and catchment hydrological models (which require data on at least daily scales and at a resolution of perhaps a few square kilometers). A variety of “downscaling” techniques have been developed (Wilby and Wigley, 1997) and used in hydrological studies. These techniques range from simple interpolation of climate model output (as used in the U.S. National Assessment; Felzer and Heard, 1999), through the use of empirical/statistical relationships between catchment and regional climate (e.g., Crane and Hewitson, 1998; Wilby et al., 1998, 1999), to the use of nested regional climate models (e.g., Christensen and Christensen, 1998); all, however, depend on the quality of simulation of the driving global model, and the relative costs and benefits of each approach have yet to be ascertained. Studies also have looked at techniques for generating stochastically climate data at the catchment scale (Wilby et al., 1998, 1999). In principle, it is possible to explore the effects of changing temporal patterns with stochastic climate data, but in practice the credibility of such assessments will be strongly influenced by the ability of the stochastic model to simulate present temporal patterns realistically. The greatest uncertainties in the effects of climate on streamflow arise from uncertainties in climate change scenarios, as long as a conceptually sound hydrological model is used. In estimating impacts on groundwater recharge, water quality, or flooding, however, translation of climate into response is less well understood, and additional uncertainty is introduced Hydrological variability over time in a catchment is influenced by variations in precipitation over daily, seasonal, annual, and decadal time scales The Third Assessment Report (TAR) of the IPCC clearly states that the risks associated with climate change have the potential to undermine progress towards sustainable development, such as, damages from extreme climate events, water shortage and degraded water quality, food supply disruptions and hunger, land degradation, and diminished human health. Precipitations The effect of climate change on streamflow and groundwater recharge varies regionally and between scenarios, largely following projected changes in precipitation. In some parts of the world, the direction of change is consistent between scenarios, although the magnitude is not. In other parts of the world, the direction of change is uncertain. Peak streamflow is likely to move from spring to winter in many areas where snowfall currently is an important component of the water balance. Glacier Glacier retreat is likely to continue, and many small glaciers may disappear. Water Quality Water quality is likely generally to be degraded by higher water temperature, but this may be offset regionally by increased flows. Lower flows will enhance degradation of water quality. Flood Flood magnitude and frequency are likely to increase in most regions, and low flows are likely to decrease in many regions. Flood frequency is affected by changes in the year-to-year variability in precipitation and by changes in short-term rainfall properties (such as storm rainfall intensity). Droughts The frequency of low or drought flows is affected primarily by changes in the seasonal distribution of precipitation, year-to-year variability, and the occurrence of prolonged droughts. Water Demand and Management Demand for water generally is increasing as a result of population growth and economic development, but it is falling in some countries. Climate change is unlikely to have a large effect on municipal and industrial demands but may substantially affect irrigation withdrawals. The impact of climate change on water resources depends not only on changes in the volume, timing, and quality of streamflow and recharge but also on system characteristics, changing pressures on the system, how the management of the system evolves, and what adaptations to climate change are implemented. Nonclimatic changes may have a greater impact on water resources than climate change. Unmanaged systems are likely to be most vulnerable to climate change. Climate change challenges existing water resources management practices by adding additional uncertainty. Integrated water resources management will enhance the potential for adaptation to change. Adaptive capacity (specifically, the ability to implement integrated water resources management), however, is distributed very unevenly across the world. Non toutes les tendences peuvent être attribué au changement climatique, mais le retrait des glaicier ainsi que le déplacement des crues du printemps à l’hiver on plus de possibilité d’être causés par le changement climatique L’effets varie sensiblement d’une régione à l’autre, essentiellement à cause du changement prévu des précipitations Dans les région où la neige est un élément important du bilan hydrique, elle se déplaceront du printemps vers l’hive, Glaciers Streamflow Floods Low flows Global Framework for Climate Services

Potential Water Resources Impacts Water Supplies Water Demands Water Quality Sea water level Flood Management Drought management Waste water treatment Irrigation and Drainage Hydropower Operations Global Framework for Climate Services

Water, Energy and Climate Change Future water management activities must carefully consider strategies to reduce greenhouse gas emissions Global Framework for Climate Services

Rainfall Variability and GDP Bubble Size = GDP per capita (Blue = low interannual variability of rainfall) Developing countries face more challenging climate conditions Monthly Rainfall Variability Wealthy nations share a small window of favorable climate (low variability; moderate rainfall) Mean Annual Rainfall (cm) Global Framework for Climate Services Brown and Lall, 2006

Climate Change Adaptation: the process Water Resources Water Demand Storage Runoff GW recharge GCM Statistical downscaling / RCM E + ET Temperature Precipitation Hydrological Modelling Climate scenarios Development scenarios Socio-economic Factors Global Framework for Climate Services

Water Resources Management Entry points for Adaptations Planning new investments, or for capacity expansion (reservoirs, irrigation systems, levees, water supply, wastewater treatment) Operation & regulation of existing systems: accommodating new uses or conditions (e.g. ecology, climate change, population growth) Maintenance and major rehabilitation of existing systems (e.g. dams, barrages, irrigation systems, canals, pumps, etc.) Modifications in processes and demands (water conservation, pricing, regulation, legislation) Introduce new efficient technologies (desalting, biotechnology, drip irrigation, wastewater reuse, recycling, solar energy ) Global Framework for Climate Services

Adaptations in Water Resources Management Guiding Principles Mainstreaming climate change adaptation within broader development context Strengthening water governance and integration of land anndwat management Improving and sharing of knowledge and information on adaptation measures and invest in monitoring Building long-term resilience through stronger institutions, invest in infrastructure and well functioning ecosystems Invest in cost effective and adaptive water management as well as technology transfer Leverage additional funds through national budgetary and innovative funding mechanisms Global Framework for Climate Services

Global Framework for Climate Services Basic Messages All drivers of hydrological cycle are affected by global warming – climate change (CC) Water is the principal medium through which most people will experience CC Many tools, coping options designed for Climate Variability (CV), form the foundations for CC adaptation Socioeconomic factors, land uses, conflicts and population dynamics will dominate future conditions and modes of adaptation Huge upfront investments to avoid highly uncertain CC risks have to be dealt with in a well-organized risk management framework Global Framework for Climate Services

Global Framework for Climate Services Basic Messages Keystone for adaptation and adaptive management is a greatly expanded and improved hydromet system for monitoring, modeling and forecasting Climate information, GCMs and prediction services need to be dramatically improved Improving governance is key to CC adaptation Therefore, CC adaptation must be cast within a broader IWRM framework, and not viewed as an independently pursued analytical paradigm Global Framework for Climate Services

WORKING TOGETHER Towards SUSTAINABLE DEVELOPMENT Thank you! Global Framework for Climate Services

Geneva, Switzerland 31 August–4 September 2009 World Climate Conference-3 Better climate information for a better future Geneva, Switzerland 31 August–4 September 2009 WCC-3 therefore is making a new beginning by bringing a more integrated approach to the application of climate science and provide better climate information for a better future for the mankind. The WCC-3 is being organised in Geneva from...... Global Framework for Climate Services

Global Framework for Climate Services GFCS Goal Enable better management of the risks of climate variability and change at all levels, through development and incorporation of science-based climate information and prediction into planning, policy and practice.” Global Framework for Climate Services

Global Framework for Climate Services GFCS: Objectives Provide a cooperative framework in which all nations, International organizations, scientists and sectors will work together to meet the needs of users; Enable users to benefit from improved climate information and prediction; Mobilize climate science globally to advance the skills of seasonal-to-interannual and multi-decadal climate predictions to generate and provide future climate information on an operational basis; Foster mechanisms for sharing new advances in science and information through a cooperative global infrastructure. Global Framework for Climate Services

Global Framework for Climate Services Components of Global Framework for Climate Services Research & Modeling and Prediction Health Agriculture Transport Tourism Water Energy Ecosystem Sectoral Users Climate Services Information System User Interface Programme Climate Research & Modeling and Prediction Observations Climate User Interface Programme Government Private sector Capacity Building Global Framework for Climate Services

Climate information flow from producers to end-users Scientific and technical analysis and prediction Social and economic actions Global Analysis and Prediction Centres Global Applications Centres International User Organizations Regional Analysis and Prediction Centres Regional Applications Centres Regional User Organizations National Meteorological Centres Sector support institutions Water, Agriculture, Health….. National and local users Global Framework for Climate Services

Global Framework for Climate Services