hydrological forecasting and data assimilation the hydrocast...
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Hydrological Forecasting and Data Assimilation – The HydroCast Project Henrik Madsen
Head of Innovation, DHI
With contributions from the HydroCast team Danish Water Research and Innovation Platform, Annual Meeting, January 31, 2013
Project overview
• Research grant from the the Danish Council for Strategic Research
• Project period: 1 Jan 2012 – 31 Dec 2015
• Partners:
o DHI (Co-ordinator)
o Geological Survey of Denmark and Greenland (GEUS)
o Department of Geography and Geology, University of Copenhagen
o Department of Civil Engineering, Aalborg University
o Danish Meteorological Institute
o European Centre for Medium-Range Weather Forecasts (ECMWF)
o Institute of Applied Mathematics, Delft University of Technology
o Danish Road Directorate
o Knowledge Centre for Agriculture
o Danish Nature Agency
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Project objective To establish and test a general framework for hydrological forecasting and data
assimilation that integrates different data sources with meteorological and hydrological
modelling systems
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Time of
forecast
Hydrological ensemble forecast Hydrological data assimilation
Weather
radar nowcast
Short-range, limited
area NWP forecast
Medium-range, large
scale NWP forecast
Seasonal, large
scale forecast
Project activities - overview
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Work packages
• WP1: Combining weather radar and numerical weather prediction for short-range
forecasting
• WP2: Probabilistic hydrological forecasting
• WP3: Hydrological data assimilation
Test studies
• Test study 1: Forecasting of floods for rural infrastructure
• Test study 2: Seasonal forecasting of irrigation potentials
• Test study 3: Integration of modelling in environmental monitoring
WP1: Combining weather radar and numerical weather
prediction for short-range forecasting
• Forecasting system that combines weather
radar and high-resolution short-range NWP
modelling
• Weather radar forecast model based on a
combination of a storm cell and a radar
reflectivity tracking model
• Data assimilation of weather radar in NWP
model
• Quality control algorithms for state-of-the-art
dual polarisation weather radars
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First results of combined NWP-weather radar forecast system
Extreme rainfall event in Copenhagen 2 July 2011
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Maximum 30-min intensity
First results of combined NWP-weather radar forecast system
Extreme rainfall event in Copenhagen 2 July 2011
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Radar, 18 UTC Forecast 18 UTC, 3 hour lead time
First results of combined NWP-weather radar forecast system
Extreme rainfall event in Copenhagen 2 July 2011
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Radar, 18 UTC Forecast 18 UTC, 2 hour lead time
First results of combined NWP-weather radar forecast system
Extreme rainfall event in Copenhagen 2 July 2011
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Radar, 18 UTC Forecast 18 UTC, 1 hour lead time
WP2: Probabilistic hydrological forecasting
• Use of ensemble precipitation forecast products to
produce ensemble hydrological forecasts
Nowcast (few hours): weather radar ensemble
prediction
Short-range (< 48 hours): DMI ensemble prediction
system
Medium-range (2-10 days): ECMWF ensemble
prediction system
Seasonal: ECMWF seasonal ensemble prediction
system
• Framework for quantification and propagation of
different uncertainty sources in the hydrological
forecast system
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DMI’s limited-area, short-range ensemble prediction system
• Based on the HIRLAM model
• 0.05º horizontal resolution
• 25 ensemble members
Initial and lateral boundary condition
perturbations
Model physics perturbations
• 54h forecasts, four times per day
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DMI’s limited-area, short-range ensemble prediction system
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WP3: Hydrological data assimilation
• Multi-variate hydrological data assimilation based
on the MIKE SHE hydrological modelling system
• Generic data assimilation framework that uses
the open modelling interface (OpenMI) standard
and links to the OpenDA data assimilation
toolbox
• Assimilation of in-situ data (runoff, groundwater
levels, soil moisture profiles) and remote sensing
data (soil moisture, land surface temperature)
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Hydrological data assimilation - Example
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Simulated heads with DA Prediction uncertainty
Optimising the monitoring effort
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Environmental state
uncertainty
Costs
Optimal design of monitoring
effort (modelling + monitoring
network)
Test study 1: Forecasting of floods for rural infrastructure
• Test the data assimilation and forecasting techniques developed with respect to short-
range forecasting of flooding at a motorway infrastructure at Silkeborg
• Flooding is caused by a combination of rising groundwater levels and overland flow
generated by heavy rainfall
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MIKE SHE model setup
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Test study 2: Seasonal forecasting of irrigation potentials
• Test the probabilistic hydrological forecasting
tools for seasonal forecasting of river flows to
determine the potential amount of irrigation
water to be abstracted for maintaining a given
minimum flow
• Two forecast horizons considered
Forecast mid-February to be used for
planning of agricultural crops
Forecast mid-April to be used for issuing
irrigation permissions
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Test study 3: Integration of modelling in environmental
monitoring
• Test the developed multi-variate data
assimilation system for monitoring of the
hydrological state at catchment scale
• Application to the Skjern catchment
using data collected as part of the HOBE
center (www.hobecenter.dk)
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Main project results
• A methodology for combining weather radar and NWP modelling for short-range
forecasting.
• A seamless probabilistic hydrological forecasting system, considering short-range,
medium-range and seasonal forecasting.
• A multi-variate hydrological data assimilation system.
• Test of the developed hydrological forecasting and data assimilation methodologies in
three studies.
• Recommendations for local and central authorities on use of hydrological forecasting
and data assimilation.
• Three graduated PhD students and two completed Post Doc studies.
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Thank you for your attention Henrik Madsen
[email protected] This work was carried out with the support of the Danish Council for Strategic Research as part of the project “HydroCast – Hydrological Forecasting and Data Assimilation”, Contract No. 11-116880 http://hydrocast.dhigroup.com/ © DHI #21