1. Climate Change impacts on water resources and utilities
Lia van Wesenbeeck, ACWFS, VU University
Joint work with Fayez A. Abdulla, Hani Abu Qdais, (JUST), Wim van Veen, Ben Sonneveld, and Max Merbis (ACWFS)

2. Overview of presentation
The problem
Predicting climate change for the JRB
The Water Economy Model
Scenario specification
Outcomes
Discussion

3. The problem
Climate change is likely to affect water availability across the globe
Also the Jordan River Basin (JRB) is going to be affected
The region already experiences major challenges related to water
Hence, important questions are:
How will climate change affect rainfall?
What is the impact of predicted rainfall patterns on
Agriculture
Human consumption
Water resources

4. Predicting climate change for the JRB
Global Circulation Models (GCMs) are
used to project the climate change on global and continental levels.
But: has low resolution (100–500 km).
downscaling techniques have been developed to build relationships between GCMs output and subgrid climate variables precipitation and temperature

5. Downscaling and extrapolation
Earlier work by Prof Abdulla focused on downscaling GCM prediction to the Yarmouk river basin
Using different scenarios
In this paper, these downscaled results were taken as point of departure for extrapolation to the Jordan River Basin

6. Extrapolation of Yarmouk forecasts
Downscaled climate change scenarios
daily data covering the period 1 January December, 2100
23 stations in the Yarmouk Basin.
Daily precipitation data were aggregated
spatially into six districts that fall within the Yarmouk Basin
temporally into six cohorts of 20 consecutive years of annual rainfall data
Relative changes were calculated:
over 40 (average of minus )
and 80 (average of minus ) years were calculated
And plotted against a South-North gradient.
A linear function using relative changes as dependent and the North coordinate as dependent variable was used to predict the precipitation changes for all districts in the JRB.

7. Scenario specification

8. The Water Economy Model
Developed within SIDA-sponsored project
Partners:
American University of Beirut
Al Quds University, Palestine Territories
Arab Center for Studies of Arid Zones and Dry Lands (ACSAD)
Jordan University of Science and Technology (JUST)
Amsterdam Centre for World Food Studies (ACWFS)

9. Model dimensions 48 districts (s) 26 two-weekly time steps (t)
Daily rainfall calibration and simulation
5 layers (l)
3 pollutants and pure water (h)

10. Schematic representation

11. Water quality Representation of pollutants
Salinity
Biological Oxygen Demand (BOD)
Nitrate
Pollutants dissolved in water
Also for pollutants, balances hold!

12. Modelling Impact on agriculture
Farm response functions

13. Scenario consequences: less run-off to the river

14. Scenario consequences: less extraction from the rivers

15. Scenario consequences: less recharge

16. Scenario consequences: limited changes in household demand
Change relative to baseline
Baseline water demand

17. Impact on agricultural revenues

18. Discussion: initial shock and system response

19. Summarizing the outcomes of the scenario
the reduction in rainfall is a major shock
partly compensated by reduced evaporation (300 mcm less)
river flows are substantially lower and, hence, also river extraction
the immediate effects on human demand remain relatively limited
however, recharge is very negatively affected (not sustainable)
also outflow to Dead Sea substantially lower (20 mcm)

20. Thank you

21. Mathematical representation
Extremely rich model!
Yet, mathematical representation is simple and transparent:
Extraction output
Return flow consumer
rainfall
Natural inflow
Consumer demand
Available for natural outflow
Extraction demand