Catchment Change Network.net

The Land Use Futures Project has taken a broad and overarching look at the future of UK land use over the next 50 years. It demonstrates that there is a strong case to develop a much more strategic approach: to guide incremental land use change, incentivise sustainable behaviours, and to unlock value from land.This report shows that a reappraisal is vital to help address major challenges ahead – for example, relating to demographic shifts, climate change, and rising demand for commercial and residential development in areas such as the South East of England. The challenge is to meet the rising expectations which will come with rising incomes; and to deliver a wider range of sustainable benefits from land. In particular, a more coherent and consistent approach is needed for managing the growing demands on land – at different levels of Government, and across the wider community of stakeholders involved in the many land use sectors.

Find the Main Reports and Evidence Summaries here

A CCN Water Scarcity Focus Area Workshop Wednesday 10th February 2010

Aims and Objectives (Enda O’Connell – Newcastle University)

• To determine how climate projections can be used in water resource assessments by water companies in terms of what we know currently, what we need to know and what research needs can be identified
• Key issues around incorporating UKCP09 within revision of PR09 business plans (by Nov 2010)
• Lack of spatial correlation and inter-annual variability in UKCP09 weather generator (especially long term characteristics)
• Demonstrated need for a move towards risk-based decision making

Chris Kilsby – Towards probabilistic water resources assessment. (Newcastle University)

• Overview of UKCP09 Weather Generator
  • daily and hourly time resolution
  • generates rainfall series with other weather variables derived from regression relations
  • reproduces extremes but not directly fitted to extremes
  • climate model change factors used so implicit bias corrections
• Climate Model and Weather Generator Limitations
  • mismatch between RCM models and observations – anomalies in rainfalls and extremes – climate models underestimate frequency of the blocking systems which cause droughts
  • seasonal and inter-annual variability under-estimated- problem of “5 season” variability
  • currently works for individual sites – for larger scales need to use RCM outputs or Newcastle spatial rainfall generator (FRACAS project )
  • See for example using Thames Catchment (Using probabilistic climate change information from a multimodel ensemble for water resources assessment)
  • more needs to be done for realistic long term variability

Steven Wade -UKCP09: An update from UKWIR- Impacts of climate change on river flows (HR Wallingford)

• Issue of climate change and headroom to better understand risks and probability of failure – A 6 week rapid assessment for UKWIR
  • Wish list includes historical drought data (1901-1902- three driest years since 1815)
  • Need to understand and factor in land use change (current assumption of no change)
  • Need to understand vulnerability of areas to long-term drought
  • Need for consistent methods across planning and water supply

Glenn Watts – UKCP09: Update from the EA (Climate Change Science Manager, EA)

• Key issue is one of using UKCP09 consistently across the EA
• JBA leading on a project to introduce UKCP09 in EA
• Percentage changes in average monthly flows up to 2100
• RCMs in context of 10000 change factors
• How to use in next planning round – does it matter?  Droughts, heatwaves, other extremes, surface/groundwater deployable outputs, headroom, outage?  Demand?
• Working with CEH on catalogue of historic droughts- improving resilience

Jim Hall -Principles for risk-based decision-making (Newcastle University)

• Overview of well developed principles of risk-based water management  and sources of uncertainty – aleatory (random variability – which may not be fully represented in the observed record) and epistemic uncertainties including residual ones
• Environment Agency (2008) Towards a clearer understanding of the relationship between the treatment of uncertainty the water resources planning process and the reliability (or level of security) of the supply-demand balance.
• What is tolerable probability of violating a level of service (including service failures that are supposed to “never” occur)?
• How much is it worth spending to reduce these probabilities?  How much are we prepared to pay for reduced risk of failure?
• Need to evaluate robustness to residual sources of uncertainty (known limitations of CP09, probabilities of scenarios, correlations & inter-annual variability…)  issues of sensitivity (what are the most important factors) and robustness
• UKCP09 a useful stimulus to  promote a probabilistic approach around water resource planning
• Are some management policies more robust than others? How much is it worth paying for robustness?

Alison Browne – – Adaption and resilience in a Changing Climate (Lancaster Environment Centre)

• Overview of a new EPSRC-funded Research Project assessing risks of climate change on water infrastructure and understanding water demand in S and SE England
  • Defining what is a drought? Who is it a drought to?
  • Scenarios of demand and technology
  • Understanding water use under changing circumstances
  • Re-conceptualisation of domestic water demand – individual practices – variability around averages – culture as much as price.
  • Developing a practice-based model of water demand

Breakout discussion session I

Q: What are the major practical issues associated with implementing UKCP09 projections?

Q: How are these issues currently being addressed?

• UKCP09 – record of extremes now available + observational data readily available
• Metrics for precipitation available (but not daily values)
• Access to data – could be usefully linked to UKCP09 portal
• Not able to provide spatial variability or coherence
• Some Water Companies have purchased daily (1950) monthly (1914) gridded data from the Met office
• project has historical data available for Europe
• Met Office Extremes Group – Simon Brown- drought severity and extreme rainfall work
• Fitness for purpose of these combined datasets?
• Not all companies have models to create pdf of impact (hence flow factors)
• Need to bring in UKCP09 storylines for specific purposes, particularly for adaptation strategies at local levels where no water resource models exist
• Consistency of methodologies needed for Ofwat reviews
• Multiple projects generating data for impact assessments and adaptation- to what extent could these be meshed together?
• Need for guidelines to outline how UKCP09  information can and should be used -inclusion of explicit assumptions and the need to remember learning/practice takes time
• Case study approach may be helpful

Breakout discussion session II

Q: How are various sources of uncertainty dealt with in current water resource assessment methodology?

Q: How can probabilistic climate projections be incorporated into the current water resource assessment framework?

• Headroom – incorporates multiple sources of possible uncertainty? Seems to have been sufficient to date but does it provide the best approach for testing adaptation strategies?
• Difficulty replacing tried and tested working methods across the industry- long take-up times problematic
• Difficulty in identifying how companies deal with uncertainties – different companies using different methods
• Might be beneficial to separate climate change from headroom- to understand what is the sensitivity of the system?
• EA planning guidance needs to be scalable and include probabilistic uncertainty in drought predictions
• Companies risk averse – robust / worse case approaches
• Climate change bill – associated impacts of carbon accounting?
• Barriers to change? – acceptability of greater uncertainty in UKCP09
• Water company focus…..how to improve quantification of uncertainty – what is the best method for the future – some uncertainties very difficult to quantify. Companies looking for a consensus view so working with each other and with Ofwat to move forward
• Need to understand system sensitivities and pinch points and start with sensitivity to climate
• Need for new tools and a more proactive rather than reactive approach
• Incorporating UKCP09 will hopefully unlock demand uncertainty – a key area with a history of neglect

• Importance of barriers – what is the capacity and willingness for people to include climate information as we move towards a more uncertain future? How do we communicate ideas around probability and willingness to pay?

Synthesis – Enda O’Connell (Newcastle University)

• Current ways of using deterministic information is open to failure
• CP09 is a driver for change -and a new approach for PR14
• Need guidance on how to move forward – adaptive measures.
• Approach of using historical data for design events is simplistic and limited: need longer records and better drought frequency analysis (nationally coordinated and using regional frequency analysis analogous to flood risk case)
• How to build CP09 into current methods? – unless it is regulated, WCs won’t do it.
• Methods should be proportionate to level of risk so more detailed analysis needed when investment is large. What is a proportionate amount of analysis?
• Government requirement for CC adaptation across all sectors based on CP09 may force WCs to do it
• How do we begin defining an acceptable level of lack of water?
• Issue of level of investment in R&D – Thames2100 considered investment of £4billion and had R&D budget of £4M. Ofwat’s Notified Items total is £1.4billion so proportionate R&D investment would be £6million.
• Need to communicate to the Water Industry that benefits would result in better decisions- how? In terms of probability and willingness to pay
• Water Innovation Platform for TSB – opportunity to make case for R&D on CC/CP09 as part of £100M case to TSB for Water Innovation Strategy
• Need to pilot new approaches on longer time scale than AMP cycle. Need to make a case to Ofwat – demonstrate what is fit-for-purpose approach through pilots. Analogy with other industries.
• Use of CC snapshots no longer valid – dynamic information should be used – integrated with information from other sources eg historic information etc. Need framework to do this/incorporate into decision-making
• EPSRC has invested in research on capacity building/adaptation. Barriers in WI to introducing new information: long-term problem – need to look beyond short-term.
• Need case studies to demonstrate benefits (eg as in flooding)
• Epistemic uncertainties (e.g. from demand or emission scenarios) could be treated separately/differently from probabilistic CC information: perhaps allows a compromise approach retaining headroom method, splitting out CC impacts on resource alone to be treated with probabilistic method
• No possibility exists in the current framework for inter-regional analysis and transfers to be considered

bachelorarbeit binden köln

Here are some thoughts arising from participating in a recent EU IMPRINTS project meeting (held at Stresa by the shore of Lake Maggiore but accompanied by snow!). The IMPRINTS project (see www.imprints-fp7.eu) overlaps with CCN in being concerned with flash flood and debris flow forecasting although there is an emphasis on Mediterranean case studies. As such it is concerned with risk and uncertainty, catchment change and climate change. Various hydrological models are being used, various ensemble forecast inputs are being used, some simple forecasts of land use change are being used, some climate change projections will be used. A number of practitioners from the case study basins are involved in the project, particularly in asking some difficult questions of the researchers about the meaning of the uncertainties that are being estimated, and whether flash floods and debris flows are likely to be more common in future.

One of the really interesting questions that arises in such a project is concerned with scale.  The predictions from distributed hydrological models are driven by either radar or numerical weather prediction (NWP) products at grid scales of 1 -10 km. Hydrological model parameters are also estimated at scales that can be larger, or may be calibrated or conditioned at larger catchment scales. Locally damaging flash floods and debris flows can be triggered by rainfall variability, interacting with local antecedent patterns of soil water, at still smaller scales. There is therefore uncertainty in how the larger scale might inform the smaller scale in evaluating potential risk.  One strategy that has been explored in the Imprints project is to run the hydrological model for a long simulation period driven by the same input product that will be used to drive longer term forecasts (the COSMO NWP 30 year reanalysis in Imprints) and then define a level of risk relative to the frequency of occurrences in the long term simulation.  This allows an first assessment of risk from 5 days ahead, and assessing consistency in any high risk locations as a potential event gets closer.

 This should be a useful tool in detecting alerts to potential flash flood and debris flow situations.  It is, however, too crude a tool for deciding about more detailed local warnings at shorter times.  This needs more accurate assessments of the spatial estimates of rainfalls, coupled with more detailed hydrological modelling of antecedent conditions and runoff generation to give more precision in localizing potential flash flood and debris flow sites (possibly at sub-grid scales).  Radar nowcasting can give rainfall inputs down to 1 km scales, but accuracy decreases rapidly with lead times. At longer times, these estimates can be blended into the outputs from ensemble NWP, but NWP systems are not tuned towards giving accurate precipitation estimates in 12 to 24 hour time scales. In the hydrological model, it will be difficult to identify local parameter values and sub-grid variability in predicting the antecedent conditions and runoff generation.

Thus, the estimation of local risk at lead times that will be useful for warning purposes will be uncertain, in ways that mean that it will be difficult to estimate the uncertainty (some studies that have been done so far suggest that the range of uncertainty in 5 day ahead forecasts based on the COSMO-LEPS NWP ensemble can certainly bracket what actually happens – but because the uncertainty bounds are so wide). This suggests that some “rules of thumb” might need to be invoked – which might again take the form of assessing relative risk.  Just how high does the estimated local grid scale risk at different lead times have to be before a local warning should be issued?  And just how does this vary in space? The IMPRINTS project aims to explore some (fuzzy) rules for such assessments. Ideally, the rules would be evaluated or validated on the basis of assessing a past sequence of estimates relative to actual occurrence of flash floods and debris flows causing damages to communities at risk. But, such occurrences are rare by nature – the extremes of a distribution of events – and events that did not cause significant damages in the past might not have been recorded.  This implies that future events might then be critical in assessing and refining the system. But the IMPRINTS project lasts only 3 years: this suggests that the tools developed need to be simple enough to be refined by practitioners who have responsibility over longer periods of time.

But, longer periods of time also imply catchment change both in land management and climate variabilities or changes.  The predictions of both are locally highly uncertain, although it would be feasible to run the hydrological model under different potential scenarios by using stochastic realisations of both land use and future weather to modify past spatial patterns of inputs (this is an area of clear overlap with CCN).  At the IMPRINTS meeting there was a discussion about whether such highly uncertain predictions could be informative for future decision making – over and above some other means of deciding on the value of investment to offset the potential of future damaging impacts. This is a recurring theme in impact studies and research funding. Nearly all such studies have an underlying concept based on a risk-based decision framework: estimate the probability of future outcomes and the costs of mitigation to prioritize investments that will have most value. This is one evidence-based strategy that can be used to justify major government investment on mitigation measures. 

The case of the Kielder reservoir in Northumberland is perhaps instructive in this respect.  Kielder was designed to service the growth of heavy industry in the north-east of England.  It was commissioned in 1981, just before the decline of heavy industry in the north-east of England. The north-east is now well protected against potential future water shortages but not because of the precision of future projections of risk – which were quite wrong in this case.  But investments in mitigation strategies still require prioritization.  Even if we only consider flood risk, there are always many more demands for spending on defence measures than money allocated each year.  Prioritization in that case is based on rules for (a rather simple and largely deterministic) cost-benefit analysis.  Is it possible that detailed studies of other types of impacts of future change could lead to similarly simple rules for prioritization (for example in the way in which OFWAT will require that climate change be incorporated into the next AMP submissions by the water utilities, to cover the period 2015-2020)? And how should these rules reflect the uncertainties underlying the estimation of impacts? Built-in storage and an improved user interface are reportedly on the cards for such an upgraded apple tv, though we won’t know for sure until, or indeed if something is announced

The aim of this technical conference will be to share the latest information and experiences concerning emerging contaminants in drinking water and advanced treatment technologies, as well as the regulatory perspectives on these topics. Some of the discussion questions for the day will include:

• What is the strategy for emerging and sometimes seemingly “untreatable”contaminants?
• What have been the recent experiences and what is the practical advice for implementing and operating advanced treatment technologies in water treatment works?
• What are the carbon footprint and cost implications of treating to increasingly higher water quality standards? How does this relate to PR09 implementation?
• What should be the water quality research priorities to start to address now, in preparation for PR14?