CIRED laboratory

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CIRED laboratory

HYPATIA NASSOPOULOS, PATRICE DUMAS, STEPHANE HALLEGATTE

CLIMATE CHANGE, PRECIPITATIONS AND WATER MANAGEMENT INFRASTRUCTURES

Water in Africa:Hydro-Pessimism or Hydro-Optimism?CEAUP, 2-3 October, Porto Portugal

Mediterranean r.+ CC + Water = ?

Ø 7% world’s population

Ø 3% world’s water resources, temporal and spatial variability

Ø Climate change: change in

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Ø Climate change: change in precipitation patterns, decrease

Climate change and Hydraulic infrastructures

Ø Present: stationary climate without taking into consideration climate change

Ø When variability increases, increasing dam and reservoir dimensions allows to capture more inter-annual variability until all is captured

Ø How to keep a satisfactory level of reliability by optimizing the available resources?

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Ø Small mountainous catchments in Algeria and Greece

Ø Sensitivity analysis of climate model choice on the hydraulic infrastructure’s Optimal Dimension

Ø Cost Benefit Analysis of different dam heights under climate change optimalstorage capacity

ØSimulate inflows under different constant precipitation and temperature changes by using local run-off monthly coefficients

ØSimulate dam operations (monthly) using simple rules:

Ø Serve fixed demand

Simulation of dam operation

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Ø Serve fixed demand

Ø Overflow when inflow exceeds storage capacity

Ø If available water less than demand, consider that demand can not be reliably satisfied

ØCompute demand at 95% reliability for different inflow changes

ØIPCC models output under A2 scenario è linear trends of precipitation change

ØHypothesis of demand adapting to the available resources

Inflow and demand under climate change

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ØEach year the annual demand at 95% reliability for this inflow change is used

Investment decision, Cost Benefit Analysis

ØCost: Rock fill dam, trapezoidal section, local height/volume geometryØBenefits:

ØDt Demand at 95% reliability with climate change as computed previously

ØWater price per m3 p

ØDiscount rate ρ

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ØDiscount rate ρ

ØNPV= (∑(1/(1+ρ))t p Dt 0.95)-Cost

ØFor each IPCC model, demand at a fixed level of reliability,water price and discount rate, we find the storage capacity which maximises the NPV

Results

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Results

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Results

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Results

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Conclusions

ØOptimal storage capacity increases with increasing precipitations

ØOptimal storage capacity increases with increasing variability

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ØFor the 12 models precipitation and variability are correlated

ØWide range of optimal storage capacity

obrigada!

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