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Background & Motivation: What does Climate have to offer? Water and CRM Technical Workshop and Training Addis Ababa, June 30 – July 2, 2009 Credits: IRI, Upmanu Lall, Casey Brown, Dave Watkins. - PowerPoint PPT Presentation
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Background & Motivation:What does Climate have to offer?
Water and CRM Technical Workshop and TrainingAddis Ababa, June 30 – July 2, 2009
Credits: IRI, Upmanu Lall, Casey Brown, Dave Watkins
260 international basins: +/- tensions: longstanding, always,
growing with demand
“Fierce competition for fresh water may well become a source of conflict & wars in the future.”
Kofi Annan, March 2001
Source: Grey & Sadoff, World Bank
Semi-Arid and Arid Sub-Tropics and Tropics & Areas w/ High Population Density
By 2025 two thirds of the people in the world are expected to live in areas of water shortage or stress.
In the 20th century the world population tripled – while water use multiplied six-fold!
Source: Vorosmarty et al 2000
Climate change or just people?
Source: Vorosmarty et al 2000
Pop + Consumption= Demand
• 54% of annual available fresh water is currently being used world-wide
• Assuming current consumption, 70% will be used due to population growth alone by 2025.
• For developed country per capita consumption 90% will be used by 2025.
Water Availability
Shiklomanov
1.7 x decrease
4.5 x decrease
7.5 x decrease
Annual Variability of Rainfall
Economic Impact of Climate Variability
-80
-60
-40
-20
0
20
40
60
8019
82
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
year
per
cen
tag
e
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
rainfall variation around the mean
GDP growth
Ag GDP growth
Ethiopia: Rainfall, GDP and Agric. GDP
World Bank
-80
-60
-40
-20
0
20
40
60
8019
82
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
year
per
cen
tag
e
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
rainfall variation around the mean
GDP growth
Ag GDP growth
Ethiopia: Rainfall, GDP and Agric. GDP
-80
-60
-40
-20
0
20
40
60
8019
82
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
year
per
cen
tag
e
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
rainfall variation around the mean
GDP growth
Ag GDP growth
Ethiopia: Rainfall, GDP and Agric. GDP
World Bank
Source: World Bank 2005
Development Trajectories in River Basins
Development Utilization Allocation
The Message
An imminent freshwater crisis• Demand > Supply• Access to safe drinking water: currently poor • High variability in supply Major investments needed
for growth• Potential for trans-boundary conflict• Climate Change: Cause or Effect? Water is the major
uncertainty
The Challenge
• Social and institutional factors often dictate resource management strategies
• Climate is a major determinant of risk
• As understanding of climate improves, how can we adapt traditional management strategies to use this new information to reduce societal risk and improve system resilience ?
• How do we balance the needs of a local resource manager with products that convey large scale, technical and yet uncertain information ?
• How do we judge failure or success ?
The Motivation
• Adaptation to climate change for water resources will require a change from a business as usual approach
• The climate is no longer stationary with increasing climate variability and changing normals
• The temporal structure to variability is not static
• Risk varies different needs
• New climate science is needed for water resource managers
Managing Water Resource Systems
• Balance Water Supply and Demand
• Historical rules for resource allocation
• How much, and when should these rules be modified ?
• How do we assess and communicate potential impacts of action & inaction ?
Health
Human Activity
Energy
Climate
Water
Agriculture
New City
Irrigated Farms
Irrigated Farms
Dam 1
Dam 2
Dam 3
Electric Grid Well Field
Muddy River
The Question
What can Water Resource Managers do?
Climate Risk Management (CRM)
Climate Risk Management
One definition: “CRM focuses on pressing issues of here and now while factoring in projected changes” (WB)
Protecting against climate hazards so climate opportunities can be utilized
Methodology to increase decision-making as a major pathway to adaptation for climate change by leveraging climate science
Key Issues
How should climate change be addressed?
• It’s an open research question
• Much can be gained by learning from those actively engaging the concept of nonstationarity of climate in practice. Case studies a key start.
Recommend a technical assessment with weaknesses exposed.
• Understanding of climate impacts on water systems is the starting point
• Historical data remains the most important source of climate information for any water system
• Solutions/adaptations should be identified, evaluated and implemented via IWRM approach
Integrating Management of Climate Risks
An operational definition:
1. Identify hazards associated with climate risks (of all time scales) to the water system
2. Characterize the climate risks
3. Propose/Assess portfolio of solutions/adaptations to key climate (and other) risks
Integrating Management of Climate Risks
1. Identify hazards associated with climate risk to
the water system
• What are the key climate challenges that the system faces now (e.g., frequent drought, flood events, variable flows)
• What damages occur as functions of these events?
• Where are the impacts felt? Are there distributional effects? Is the environment considered/protected?
• Are there opportunity losses due to risk aversion associated with current climate risks?
Integrating Management of Climate Risks
2. Characterize hydroclimatic risk
• What are the probabilities, recurrence periods, etc. of hazard causing events
• Is there spatial or temporal structure?
• Are there probable/predictable changes expected?
• What are the most plausible future scenarios and the uncertainty associated with them?
• How do these risks compare to the social, economic, demographic and environmental challenges the water system faces (severity, uncertainty)?
Integrating Management of Climate Risks
3. Propose/Assess portfolio of solutions/adaptations to
Climate Risks
• Incorporate uncertainty of climate futures in the decision process
• May favor flexibility over structure (soft vs hard approaches)
• Solutions have spatial and temporal characteristics that modulate appropriateness based on the climate risks
• Risk solutions are dependent on timeframe of analysis:
- Operational – fixed infrastructure, certain sunk costs
- Planning – infrastructure and other system decisions
Application
Move from Static to Dynamic Risk Management• Changing climate• Changing goals• Changing population demographics and landscape
“Hard” and “Soft” Technologies• Design & Operation of Structures• Allocation Rules and Water Rights• Risk Sharing and Reduction Strategies
Develop ideas through examples at multiple scales
Application
Design flexible, adaptable systems – reliability no longer assured
Suite of options:
• Infrastructure: important, but effective range likely exceeded
• Economic instruments: water banks, options, contracts
• Seasonal forecasts
• Flexible operating rules
• Insurance
• Characterize uncertainties / probabilities
Redundancy in the system
Continuous system performance
Good results payoff in long run
Application
Can we leverage applications of climate science to reduce (exploit) negative (positive) impacts of climate variability?
Application - Forecasts
Reservoirs operated without forecasts in risk averse mode
• Anticipating drought of record in every year
• Water is kept in the reservoir as a reserve for a drought, instead of being delivered to irrigators or being used for hydroelectricity production
Forecasts provide enhanced estimate of drought risk
• Identifying opportunities in years when drought risk is low (eg La Niña)
Source: C. Brown (IRI)
Application - Forecasts
Statistical Model
Photo: MWSS
Sea Surface Temperatures
Global Climate Model
Historical Inflow Observations
Forecast Inflow for OND 2002
RAINFALL
WINDS
Cross-Validated Model
Source: B. Lyon
Application - Forecasts
Probability of exceeding a seasonal rainfall threshold
Choose parameter, quantity (i.e., number of dry spells of 7 or more days), and statistic of interest (i.e. probability of exceedance)
Application - Health
Suitability for Malaria Transmission
Application - Agriculture
Index Insurance for Crops
Bridging Climate into Risk Management
Summarizing Climate into Risk Management
= tailored probabilistic climate information within a specific institutional and policy
setting
relevant variables:eg: reservoir inflow
dry spell or flood risk
PDF/CDF“prob. of exceedance”
* historical* predictive
* real-time monitoring
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