background & motivation: what does climate have to offer?

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