UK drought: overview of current research and priority
research gaps
Jamie Hannaford Centre for Ecology & Hydrology, Wallingford, UK
Water Security Knowledge Exchange Programme – Drought Management Workshop, Thurs 19th April 2012
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Monitoring the current drought situation
“Elsewhere, and in the absence of near-
record late-spring rainfall, recessions will
continue with the prospect of overall
groundwater resources being comparable
with, or below, the lowest in the last 100
years by the autumn”.
Ewelme Brook, 16 April 2012
Monthly summaries of hydrological situation
Droughts have different identities
2003 2004 - 6
Spatially Extensive Short duration (9 months) Limited water resources impact
Summer drought
Regional focus Very long duration (22 months) Substantial water resources impact
Multi-year drought
Part 1: a (very) brief survey of
recent research
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Drought catalogues give information on severity, duration, seasonality of
historical events
1975 - 76
1984
1988 - 92
2003
Historical droughts: drought catalogues
Other work: Meteorological Droughts: Eleanor Burke (Met Office) Groundwater Droughts: John Bloomfield (BGS)
Historical droughts – the long view
Major Water Resources Droughts in E & W (Marsh et al. 2007)
PDSI, 1700s - present Neil MacDonald, Beverley Todd, U. Liverpool
Which historical droughts should be used to test water supply systems? Are recent droughts representative?
1976
1890s
• 2010 - ??
• 2004 – 6
• 1995-97
• 1990-92
• 1975-76
• 1959
• 1933-34
• 1921
• 1890-1909
• 1887-88
• 1854-60
• 1798-1808
Using historical droughts to inform management
• Identify worst long
droughts in historical
record
• Develop synthetic
droughts
• Use these to test
resilience of water supply
systems in a simulation
workshop
Worst historical long droughts on the Ely Ouse
EA/Defra/HR Wallingford/CEH/UKCP/ - Watts et al. 2012
The bigger picture: spatial coherence
The Global Drought Monitor
drought.mssl.ucl.ac.uk/
Examining spatio-temporal evolution of historical droughts (Ben Lloyd-Hughes,
Walker Institute)
Droughts evolve slowly and affect large areas: can spatio-temporal evolution inform drought
management?
Other work: European Drought Observatory (JRC) Coherence of summer drought in Europe (UEA) Synchronicity of droughts at European/global scale (WATCH project)
Climatic drivers of UK and European drought
Parry et al. In press
Regional streamflow deficits
Are there recurrent patterns driving historical droughts? Can these aid monitoring/early warning?
Negative NAO during 1962 – 1964 drought Pressure anomalies (mb)
Other work: NAO and seasonal flows (Cedric Laize, David lavers, CEH) Weather Types (e.g. Hayley Fowler, Newcastle; Ian Phillips, Birmingham; Anne Fleig, U. Oslo)
Drought modelling
Observed WaterGAP JULES MPI-HM GWAVA HTESSEL
• Can we improve the simulation of drought characteristics in hydrological models to inform drought management?
• Why? So we can use models to extrapolate in space, and extend into past/future
Reproduction of historical drought characteristics using 5 large-scale hydrological models
Prudhomme et al. 2011
Part 2: research gaps
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Indicators and monitoring
• There are dozens of indicators out there: which are most relevant for drought management?
• Can we develop consistent indicators for all elements of the hydrological cycle (e.g. including soil moisture)?
Vidal et al. 2010
Tracking the evolution of the 1976 Drought in France using indicators of precipitation, soil moisture and river flow
Precip
Soil M
Flow
Characterising severity and impacts
• How do droughts impact aquatic ecology?
• How do water management interventions influence drought severity?
• Can historical precedents inform drought management – how best to
use historical analogues to inform decision making.
Impacts of the 1976 drought
“most significant impact on water resources of
all 20th century droughts”
“water quality problems, reduction in extent of
the river network, loss of aquatic habitat”
“forest fires raged - 50,000 trees burned in one
episode in Hurn Forest”
“136 drought orders - water shortages and
rationing - standpipes introduced”
“water policy changed as result, incorporating
water transfers and supply augmentation”
1976
BBC
Guardian
Early warning and outlooks
• Can we improve the skill of seasonal forecasts in the UK?
• Are there alternative methods for producing “hydrological outlooks”
using historical analogues or spatial coherence?
• How to operationalise existing science?
Seasonal streamflow forecast from Australia A Hydrological Outlook for the UK?
Priority Research Needs?
• Improve drought monitoring by developing drought indicators which
have relevance to users
• Use indicators to quantify drought severity and characterise impacts
(both ecological and water resources) of historical droughts
• Test how well models reproduce drought characteristics and verify them
against current/recent drought events
• Examine large-scale spatiotemporal evolution of drought and climatic
drivers of drought in UK and Europe
• Develop new tools to translate this science into improved monitoring
and early warning systems
• Assess the feasibility of producing hydrological outlooks to guide
drought management decisions
Further Information
• The National River Flow Archive:
http://www.ceh.ac.uk/data/nrfa/
• EU-WATCH project:
http://www.eu-watch.org/
