MIKE HYDRO RiverRainfall Runoff modelling – overview of RR modelling options... Rainfall Runoff Model types MODEL TYPES • Lumped • Semi-distributed • Distributed Model-type available in
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Rainfall Runoff modelling – overview of RR modelling options
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Content:
• Catchment delineation – Graphical / manual / Import
• RR models
• Options
• Linkage to HD-models
• Results
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Why Rainfall Runoff modelling?
• Calculate catchment runoff from precipitation
• Effects of land use change
• Climate change studies/coupling with atmospheric models
• Forecasting of floods/droughts
• Streamflow extension or gap-filling using Meteorological data
• Surface water/groundwater interaction
• Simulation of spatial patterns within a catchment
• Water availability within river basins
• …
• …
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MODEL TYPES
• Lumped
• Semi-distributed
• Distributed
Model-type available
in MIKE HYDRO River
Additional model type characterisation:
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Available Rainfall runoff models :
‘NAM’ (Numerical Runoff Model)
• Lumped, Continuous model type
‘UHM’ (Unit Hydrograph Method)
• Lumped, Event-based model type
‘Time-area’
• A conceptual model where runoff is controlled by initial and continuous hydrological losses
‘Kinematic wave’
• A non-linear model based on the kinematic wave approach
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THE RAINFALL-RUNOFF PROCESS
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PROCESS DESCRIPTION
• Describes the land phase of the hydrological cycle
• NAM is a lumped, conceptual model:
− Lumped catchment regarded as one unit, parameters are
average values
− Conceptual based on considerations of the physical processes
© DHI The Rainfall Runoff process (NAM)
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PROCESS DESCRIPTION
SOIL MOISTURE PROFILE
Depth
L
Lmax
GWL
Sy
GWL
GROUNDWATER STORAGE
Root Zone
GWPump
BF BaseFlow GWLBFo
CKBF
LOVER ZONE STORAGE
Lmax
L
BFu
DL
CAFlux
Umax
OF IF
G
RAIN
SNOW
SNOW STORAGE
P Ps
QIF InterFlow Pn
CK1 CK2
QOF Overland Flow Ep
Ea
Owp Ofc Osat SOIL MOISTURE PROFILE
Depth
L
Lmax
GWL
Sy
GWL
GROUNDWATER STORAGE
Root Zone
GWPump
BF BaseFlow GWLBFo
CKBF
LOVER ZONE STORAGE
Lmax
L
BFu
DL
CAFlux
Umax
OF IF
G
RAIN
SNOW
SNOW STORAGE
P Ps
QIF InterFlow Pn
CK1 CK2
QOF Overland Flow Ep
Ea Owp Ofc Osat
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NAM Main parameters
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Evaporation; small peaks Usual value: 10-25 mm
Evaporation; water balance Usual value: 50-250 mm
Divides excess rainfall in runoff and infiltration Usual value: 0.01 - 0.99
Delays overland flow at the beginning of a wet season
Usual value: 0.0 - 0.7
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NAM Main parameters cont’d:
Delays groundwater recharge at the beginning of a wet season
Usual value: 0.0 - 0.7
Determines shape of baseflow hydrograph Usual value: 500 - 5000 hours
Determines shape of peaks Usual value: 3 - 48 hours
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NAM CALIBRATION
MIKE HYDRO Basin - Rainfall Runoff Modelling (NAM)
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NAM Calibration
MAXIMUM: 15 NAM PARAMETERS
• Most important for the water balance are L max , U max , and CQOF
• Remaining parameters are used for adjustment of peaks and for routing
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Activate Rainfall runoff:
RR Catchment definitions:
a) Delineation (from DEM)
b) Digitization
c) Shapefile Import
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Combined catchment
• Combine outflow from several individual catchments
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NAM calibration plot option
• Compare simulation results to measured timeseries
• Creates automatically a ‘Plot composer file’ with comparison plots during simulation
LIVER, Observed RunOff [m^3/s]
00:00 1973-08-20
00:00 1974-03-08
00:00 09-24
00:00 1975-04-12
00:00 10-29 0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
LIVER, Accumulated Qobs Million [m^3]
00:00 1973-08-20
00:00 1974-03-08
00:00 09-24
00:00 1975-04-12
00:00 10-29 0
20 40 60 80 100
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Coupling of Hydrodynamic and Rainfall runoff models
• Catchment connections
− Catchments links to one or multiple rivers
• River Links
− By fraction or area of catchments
− Link types:
• Point
• Distritubed
• Entire branch
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• Simulations Results
− All models; Runoff and Rainfall
• Additional results depending on RR-model selected: Example: NAM Additional Result-file content:
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