Implications of Climate Variability and Human-Induced Climate Change for Water Resource Management

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1 Implications of Climate Variability and Human-Induced Climate Change for Water Resource Management Robert T. Watson Chief Scientist and Senior Scientific Advisor ESSD, World Bank Former Chair, Intergovernmental Panel on Climate Change Water Engineering and Research in a Learning Society 30 th Biennial World Congress of the IAHR Thessaloniki, Greece August 25, 2003

2 Climate Change and the Development Challenge

3 Five development priorities were identified at the World Summit on Sustainable Development in South Africa Water 1.3 billion people live without clean water and 2 billion people live without sanitation Energy 2 billion people live without electricity Health Agriculture Biodiversity The Development Challenge 1.4 billion people are exposed to dangerous levels of outdoor pollution and about 2 billion people are exposed to dangerous levels of indoor air pollution and vector- and water-borne diseases 800 million people are currently malnourished Genetic, species and ecosystem-level diversity is being lost at an unprecedented rate 1.2 billion people live on less than $1 per day and 2.8 billion people live on less than $2 per day

4 Climate Change and WEHAB Human-induced climate change is projected to: W Decrease water availability and water quality in many arid- and semiarid regions, and increased risk of floods and droughts in many regions throughout the world E Decrease the reliability of hydropower in some regions H Increase the incidence of vector- (e.g., malaria and dengue) and waterborne (e.g., cholera) diseases, as well as heat stress mortality A Decrease agricultural productivity for almost any warming in the tropics and sub-tropics and adversely impact fisheries B Adversely effect ecological systems, especially coral reefs, and exacerbate the loss of biodiversity

5 Underlying Causes of Change The primary factors underlying climate change include: economic growth, demographic shifts, broad technological changes, and governance structures. These can give rise to: Increased demand for energy Market imperfections, subsidies that lead to the inefficient use of energy and act as a barrier to the market penetration of climate sound technologies; and failure to internalize the social costs of environmental degradation into the market price of a resource Limited availability and transfer of technology, Inefficient use of technologies, and Inadequate investment in research and development for the technologies of the future

6 Water Resources The Context

7 Water Resources Effective development and management of water resources is essential for sustainable economic growth and poverty alleviation, but: Water scarcity is growing by 2025 about half of the world s population is projected to live under conditions of water stress or water scarcity Water quality is declining Environmental and social concerns are increasing large dams The threats posed by floods and droughts is increasing because of human-induced climate change

8 Water Stress will Increase Independent of Climate Change

9 Water Has the Lowest Rate of Cost Recovery Among Infrastructure Sectors Percentage of Cost Recovery Telecommunications Gas Power Water

10 The Global Water Crisis Of 70% of water withdrawn for irrigation, half is lost to seepage and evaporation 50-60% of wetlands have been lost, altering hydrological and ecological functions 40-60% of water used by utilities is lost to leakage, theft, and poor accounting

11 The Challenges of Water Resource Management Quantity and Quality Implementation of the Dublin Principles Ecological Principle: River basin management; multi-sectoral management, (agriculture, industry, households); land and water must be managed together Institutional Principle: All stakeholders, state, private sector and civil society, especially women, must be involved in the management principle of subsidiarity action at the lowest level Instrument Principle: Incentives and economic principles to improve allocation and enhance quality - pricing policies

12 Climate Variability and Change Seasonal variability El-Nino phenomena impact of climate variability on water resources ability to predict seasonal changes in climate and manage this variability Long-term climate change impact of long-term climate change on water resources ability to predict long-term changes in climate approaches to reduce vulnerability of water resources to changes in climate

13 Climate Variability and Water Resources

14 The El-Nino phenomena leads to floods and droughts throughout the tropics and subtropics El Niño years La Niña years

15 El-Nino conditions affect temperatures and precipitation, especially in the tropics and sub-tropics C h a l l e n g e s o f a C h a n g i n g E a r t h J u l y

16 Impact of El-Nino in the Northern Hemisphere Winter

17 Zimbabwe s Rainfall Record: Note the year to year variability and the long-term downward trend

18 Source: IRI (International Research Institute for Climate Prediction Experimental Climate Forecast Division

19 Climate...Africa s unique vulnerability High year to year variability of precipitation (typically +/- 40%) and run-off -- the lower the rainfall the higher the variability Droughts are endemic and are Africa s principal type of natural disaster & major obstacle to poverty eradication Floods infrequent, yet cause major economic, social and environmental damage International character of most watercourses Low incomes, expanding populations & demand Low capacity for management of variability

20 Zimbabwe drought (1991/2): 45% decline in agricultural production, 11% decline in GDP, 62% decline in stock market, 9% decline in manufacturing output, 15% reduction in power generation

21 Drought/flood response... Options Consider drought/flood as a random natural disaster.ad hoc response: emergency programs, or Recognize drought/flood as recurring phenomena proactive and strategic approach (i) mitigation of damage to preparedness to minimize damage; (ii) preparedness to integration of climate variability in economic and sectoral policy & management; and, therefore (iii) shock to business as usual

22 A key question is whether there will be changes in the El-Nino phenomena in a warmer world The answer is that the climate will be become more El-Nino like leading to more floods and droughts

23 Human-Induced Climate Change and Water Resources

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25 Human Activities Have Changed the Composition of the Atmosphere Since the Pre- industrial Era Carbon dioxide has increased by 31% Methane has more than doubled Nitrous oxide has increased by ~15%

26 The Land and Oceans Have Warmed Implications for evaporation and evapotranspiration

27 Precipitation Patterns Have Changed

28 Heavy Precipitation Events Have Increased Over the USA Implications for the risk of the incidence of floods and droughts

29 Sea Levels Have Risen Implications for ground water in coastal regions

30 The Frequency, Persistence and Magnitude of El- Nino Events Has Increased El Niño years La Niña years Implications for floods and droughts

31 Global Mean Surface Temperatures Have Increased

32 Most of the Observed Warming of the Last 50 Years is Attributable to Human Activities

33 Climate Change An Integrated Framework

34 Projected Concentrations of CO 2 During the 21 st Century Are Two to Four Times the Pre-Industrial Level

35 CO 2 Concentration in Ice Cores and Projected Atmospheric CO 2 Concentration in Ice Core Samples and CO 2 Projections for Next for Next Years Projected (2100) Projected (2100) Vostok Record Law IPCC Dome IS92a Record Scenario Mauna Law Dome Loa Record IPCC Mauna IS92a Loa Scenario Record Current (2001) Current (2001) CO2 Concentration (ppmv) , , , , Years Before Present (BP 1950) C h a l l e n g e s o f a C h a n g i n g E a r t h J u l y

36 Global Mean Surface Temperature is Projected to Increase During the 21st Century

37 Projected Temperatures During the 21 st Century Are Significantly Higher Than at Any Time During the Last 1000 Years

38 Land Areas Warm More Than the Oceans with the Greatest Warming at High Latitudes Annual mean temperature change, 2071 to 2100 relative to 1990: Global Average in 2085 = 3.1 o C

39 Some Areas are Projected to Become Wetter, Others Drier Annual Mean Precipitation Change: 2071 to 2100 Relative to 1990

40 Extreme Weather Events are Projected to Increase higher maximum temperatures, hot days and heat waves over nearly all land areas (very likely) higher minimum temperatures, fewer cold days, frost days and cold spells over nearly all land areas (very likely) more intense precipitation events over many areas (very likely) increased summer drying over most mid-latitude continental interiors and associated risk of drought (likely) increase in tropical cyclone peak wind intensity, mean and peak precipitation intensities (likely) intensified floods and droughts associated with El-Nino events in many regions due to a more El-Nino like state no projected change in the frequency or magnitude of El-Nino s (likely)

41 Potential Climate Change Impacts Presentation will now focus on water resources

42 Water Services Climate change is projected to decrease water availability in many arid- and semi-arid regions About one quarter of the world s population is now subject to water stress or scarcity Population facing water scarcity/stress is projected to double over the next 30 years

43 Projected Beneficial and Adverse Effects of Climate Change λ increased water availability in some water-scarce regions, e.g., in some parts of S. East Asia λ decreased water availability in many water scarce regions, especially in arid and semi-arid lands in the sub-tropics λ changes in the productivity and composition of ecological systems, with forests being vulnerable will affect hydrological processes

44 Run-off is projected to change: many areas in the subtropics and midlatitudes become drier

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46 Water Resources Widespread accelerated glacier retreat and shifts in the timing of stream-flow from spring toward winter in many areas are associated with observed increases in temperature Peak steam-flow will move from spring to winter in many areas where snowfall is an important component of the water balance Projected changes in stream-flow vary regionally and are scenario and model dependent and largely follow projected changes in precipitation Water quality will be degraded by higher temperatures (flow dependent) Flood magnitude and frequency are likely to increase Integrated water resource management will enhance the potential for adaptation to change capability is regionally dependent

47 Crop Yields are Projected to Decrease Throughout the Tropics and Sub-tropics, but Increase at High Latitudes Percentage change in average crop yields for the IS 92a climate change scenario. Effects of CO 2 fertilization are taken into account and some adaptation, but not increased incidence of pests. Crops modeled are: wheat, maize and rice s, 2050s and 2080s

48 Developing Countries are the Most Vulnerable to Climate Change Impacts are worse -- already more flood and drought prone and a large share of the economy is in climate sensitive sectors Lower capacity to adapt because of a lack of financial, institutional and technological capacity and access to knowledge Climate change is likely to impact disproportionately upon the poorest countries and the poorest persons within countries, exacerbating inequities in health status and access to adequate food, clean water and other resources.

49 The Challenge of Mitigation The near-term Challenge is to achieve the Kyoto targets The longer-term challenge is to meet the objectives of Article 2 of the UNFCCC, i.e., stabilization of the atmospheric concentrations of GHG concentrations at a level that does not harm the climate system (food security, ecological systems and sustainable economic development)

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51 Stabilization of atmospheric concentrations of carbon dioxide will require global emissions reductions Stabilization Level Date for Global Date for Global Emissions (ppm) Emissions to Peak to be Below Current Levels Other greenhouse gases, which are increasing, need to be taken into account when deciding the appropriate stabilization level of CO 2 (other gases already equiv to about 100ppm of CO 2 ).

52 There is a Wide Band of Uncertainty in the Amount of Warming that Would Result From any Stabilised Concentration of Greenhouse Gases 10 Temperature change relative to 1990 (C) 10 Temperature change relative to 1990 (C ) Temperature change in the year Temperature change at equilibrium Eventual CO 2 stabilisation level (ppm) Eventual CO 2 stabilisation level (ppm) Even stabilization at 550ppm results in significant warming

53 Therefore, we need to both mitigate and adapt to climate change

54 State of Policy Formulation for Climate Change

55 The Kyoto Protocol All governments, except the US, have approved a number of core elements The flexibility mechanisms carbon trading Land-use, land-use change and forestry activities Funding for developing countries The US stated that the Kyoto Protocol was flawed policy because it was neither fair nor effective and not in the best interests of the US scientific uncertainties high compliance costs ineffective without the participation of the large developing countries

56 Differentiated Obligations It has argued by the US that the Kyoto Protocol is neither fair nor effective because developing countries are not obligated to reduce their emissions, i.e., its not in the self-interest of the US energy companies Fairness - This is an equity issue - the Parties to the Kyoto Protocol will have to decide what is fair and equitable, recognizing that: about 80% of the total anthropogenic emissions of greenhouse gases have been emitted from industrialized countries (US is currently about 25% of the global emissions 36% of Annex I emissions); per capita emissions in industrialized countries far exceed those from developing countries; developing countries do not have the financial, technological and institutional capability of industrialized countries to address the issue; and increased use of energy is essential for poverty alleviation Effectiveness - Long-term stabilization of the atmospheric concentration of greenhouse gases cannot be achieved without global reductions, hence the issue is whom should do what in the short-term recognizing the long-term challenge

57 The Kyoto Protocol Implications of non-ratification by the US Ratification is viable without US, i.e., 55 countries and 55% of industrialized country emissions Europe, Japan and Canada have ratified and are providing moral and political leadership the Russian Federation have committed to ratification - the US and Australia are isolated in refusing to ratify the Kyoto Protocol Possible parallel activities by the US US Administration has committed to a decrease of 18% in GHG per unit of GDP by 2010 (equivalent to an increase of 25-30% above 1990 levels by 2010) Congress may act to to either legislate emissions reductions or promote voluntary actions by industry Significant voluntary industry and State (e.g., California and possibly New York) activities to reduce emissions

58 Annex I and Non-Annex I Fossil Fuel Carbon Emissions: BAU

59 Developed Country Per capita Emissions far Exceed Developing Country Per Capita Emissions

60 Technologies and Policies Exist to Reduce GHG Emissions Stabilization will require emissions reductions in all regions, i.e., Annex I countries cannot achieve stabilization alone Numerous technologies currently exist in both energy supply (e.g., fuel switching, renewable energy technologies, carbon capture and storage) and energy use (transportation, industry and home use) Significant technical progress has been made in the last 5 years and at a faster rate than expected (wind turbines, hybrid engine cars, fuel cell technology, underground carbon dioxide storage) Forests, agricultural lands and other terrestrial ecosystems offer significant carbon sequestration potential globally - up to 100GtC over the next 50 yrs Without international carbon trading, Annex B costs of complying with the Kyoto Protocol, range from 0.2-2%, where-as with full Annex B trading costs are reduced to 0.1-1%. Costs could further reduced with use of sinks, the CDM and inclusion of other GHGs

61 Conclusions Current water resource management is not optimized with respect to today s climate variability and water is often wasted More equitable allocation and efficient management of water resources requires Functioning institutions (e.g., legal and regulatory), Management instruments (e.g., regulatory and financial) Development, maintenance and operation of infrastructure (e.g., reservoirs and dams) Transparency in decision-making Water rights Pricing policies, and Incorporation of scientific forecasts of precipitation (seasonally and decadal) Efficient management of water today will reduce the vulnerability of water resources to long-term climate change

62 Conclusion The Earth s climate is changing due to human activities Industrialized countries have caused the problem, but developing countries and poor people are the most vulnerable The actions of today s generation will profoundly effect the Earth inherited by our children and future generations There are cost-effective and equitable solutions, but political will and moral leadership is needed Mitigation and adaptation activities will be needed Innovative public-private partnerships and technology transfer are needed Market reform is needed reduction of energy subsidies and internalization of local/regional externalities (i.e., pollution costs) Increased public and private sector funding for energy S&T