CEG8526: Hydrosystems modelling and management
Assignment 2024-2025
Coursework 2
Background
The UK water supply industry faces several challenges due to climate change, including increased water scarcity from warmer temperatures, changing rainfall patterns, and more frequent and severe droughts. According to the 3rd UK Climate Change Risk Assessment ‘Future projections of more frequent and intense dry periods lead to concerns around the availability of public water supplies in future, especially in England and parts of Wales.
Private water supplies are also at risk. ’ The UK also faces an increased demand for water, particularly in the southeast of England, where demand is already high.
Assignment
Your overall task is to assess the impacts of climate change on flow regime and water resources on the Derwent catchment (National River Flow Archive ref. no. 28001). You should provide a written summary of your approach and analysis of the future change in catchment flow regime under climate change and the implications for water resources, providing useful planning information to the water resources sector.
A) Rainfall simulation
You should construct a synthetic time-series of rainfall data using a stochastic time-series model, with statistical properties consistent with the historical rainfall data for the
catchment, representing a baseline for the climate change assessment. You should then apply appropriate climate change projections to derive downscaled, perturbed time series of projected future rainfall (we recommend you assume the transition probabilities remain
unchanged). You should use these simulations to provide an assessment of changes in rainfall under climate change and its impacts on the catchment’s hydrology and water resources.
You should select ONE appropriate product from UKCP18 (e.g. from the probabilistic
projections or land projections from an appropriate resolution model), explaining your choice, and then analyse the projected changes for TWO scenarios - RCP8.5 plus one other scenario. You should also quantify the uncertainties in each scenario by exploring
the range of climate change projections for each e.g. an upper and lower estimate of change.
B) Modelling catchment river flow
You should then run your rainfall series (baseline plus future scenarios) through the
calibrated SHETRAN catchment model for the Derwent from which you will derive baseline and projected future flows. Using the outputs from the model you should discuss the
change in catchment flow regime, for example changes in extreme or low flows.
C) Assessment of water resource
You should then run the baseline and projected future flows through a Pywr water
resources simulation model for the Upper Derwent reservoirs, using the online platform WaterStrategy. Building on your understanding from the projected changes in rainfall and flows, you should then analyse the outputs from the water simulation to evaluate changes in water resource availability, for example in minimum and mean simulated reservoir
storage levels. You should describe and explain the projected changes, including an analysis of the uncertainties.
Your report should explain your methodology and justify the methodological approach. It should be structured in a logical manner. Your conclusions should summarise your
findings in the context of guidance to a water resources planner looking to quantify climate risk to water supplies, along with any methodological limitations and uncertainties in your approach and how you might address these in further work. You should also reflect on
additional factors that you might consider important to improve modelling in future assessments and decision-making.
A summary of the workflow for this assignment is provided on the last page for your guidance.
Formatting and indicative marking schedule
Report format: the report should be a maximum of 4,000 words (excluding titles/contents, figure and table captions, and references) and use 11pt font with normal spacing.
Marking criteria and schedule: this coursework comprises 65% of the overall module assessment. It will be marked according to the standard SAgE faculty marking criteria (see information provided on Canvas) taking into account the following:
• presentation and structure of the report, including clear figures;
• ability to investigate a problem using an appropriate experimental approach. Credit will be given for going beyond the taught material, including additional methodological developments;
• ability to understand and apply relevant hydro-informatic models to derive
appropriate quantitative outputs to support management of water resources;
• understanding of the basis for application of outputs from climate models to assess hydrological impacts;
• clarity of overall argument, supported by evidence from modelling, and supported by references where appropriate.
Marks will be allocated as follows:
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Item
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Percent Allocated
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Introduction
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5%
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Stochastic rainfall model and analysis
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15%
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Hydrological impact analysis
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25%
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|
Water system impact analysis
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40%
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Conclusion
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15%
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Submission date: Monday 20th January 2025, 2.00pm
Summary of workflow and models:
A. Stochastic rainfall model Comparison with
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• Historical rainfall simulation of N years of synthetic data
• Climate change rainfall
simulation(s) of N years using perturbed synthetic data
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Observed rainfall statistics for baseline period
Simulated rainfall from the baseline period
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B. Shetran model
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Comparison with
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• Climate change baseline simulation
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No comparison needed, as this is the
baseline run (there is no river flow record corresponding to the synthetic rainfall)
|
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• Climate change scenario simulations
(multiple simulations)
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Simulated river flow from the climate change baseline run. (Note: you do not need to use the objective functions for these comparisons).
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C. Pywr water resources model
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Comparison with
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|
• Climate change baseline simulation
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No comparison needed
|
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• Climate change scenario simulations
(multiple simulations)
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Simulated water resource outputs from the climate change baseline run.
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