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Transcript of 1 geotop-summer-school2011
Hen
ry R
oss
eau
- T
he
dre
am, 1
92
0
Riccardo Rigon, Stefano Endrizzi, Matteo Dall’Amico, Stephan Gruber
GEOtop: the making of
Wednesday, June 29, 2011
“Prediction is very difficult,
especially about the future”Niels Bohr
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Objectives
•To explain what GEOtop is;
•To enumerate the basic scheme and the basic equations
The GEOtop
•To explain why GEOtop is like it is;
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Problem: We cannot currently predict the spatial pattern of watershed
response to precipitation and cannot quantitatively describe the surface
and subsurface contributions to streamflow with enough accuracy and
consistency to be operationally useful.
Rainfall–Runoff spatial patterns
Critical issues: Watershed runoff and streamflow are affected by
heterogeneity in soil hydraulic properties, landscape structural properties,
soil moisture profile, surface–subsurface interaction, interception by plants,
snowpack, and storm properties.
Traditional lumped models cannot do it!
The GEOtop
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Problem: We would like to predict the spatial pattern of snow cover,
its volumes and its effects on runoff with enough accuracy and
consistency to be operationally useful.
Critical Issue: Also in this case we know enough of the snow
physics “in a point” but we do not have many tools to understand the
snow cover effects on larger, catchment scales. Soil freezing
substantially alter the hydraulic properties of the soils.
Related problem: snow avalanches triggering
Snowpack evolution and ablation
The GEOtop
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Problem: We cannot currently predict the triggering of shallow
landslides which eventually turns into a debris or a mudflow.
Critical Issue: Initial and boundary conditions. Landslide initiation
is affected by heterogeneity in soil hydraulic and geotechnical
properties, landscape structural and geological properties, soil moisture
profile, surface–subsurface interactions.
Landslide and debris flow initiation
The GEOtop
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Problem: Well, I do not want to steal the work to John and Kelly ;-)
Critical Issue: See their lectures
Ecohydrology
The GEOtop
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However, hydrology in winter is usually different
The GEOtop
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In spring time plants have vegetative growth
The GEOtop
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In summer: land use matter
The GEOtop
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And eventually autumn comes
The GEOtop
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“Although our understanding of individual
processes is improving, the integration of that body
of knowledge in spatially distributed predictive
models has not been approached systematically”.
Committee of hydrological Sciences NRC, 2003:
The GEOtop
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Every Hydrologist would like to have THE MODEL of IT all
But in reality everybody wants just to investigate a limited set of
phenomena: for instance the discharge in a river. Or landsliding , or
soil moisture distribution.
Any problems requires its amount of prior information to
be solved: some problems needs more detailed information of others
Introduction
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So we use different models
Introduction
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So we use different models
GEOtopFu
lly
dis
trib
ute
dG
rid
bas
ed
Introduction
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So we use different models
GEOtopFu
lly
dis
trib
ute
dG
rid
bas
ed
NewAge
Larg
e sc
ale
mod
elli
ng
Hil
lslo
pe
- St
ream
An
thro
pic
In
fras
tru
ctu
res
Introduction
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Boussinesq
Full
y C
ou
ple
dSu
bsu
rfac
e- S
urf
ace
Gri
d B
ased
So we use different models
GEOtopFu
lly
dis
trib
ute
dG
rid
bas
ed
NewAge
Larg
e sc
ale
mod
elli
ng
Hil
lslo
pe
- St
ream
An
thro
pic
In
fras
tru
ctu
res
Introduction
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Boussinesq
Full
y C
ou
ple
dSu
bsu
rfac
e- S
urf
ace
Gri
d B
ased
PeakFlow
GIU
HPea
k f
lood
s
So we use different models
GEOtopFu
lly
dis
trib
ute
dG
rid
bas
ed
NewAge
Larg
e sc
ale
mod
elli
ng
Hil
lslo
pe
- St
ream
An
thro
pic
In
fras
tru
ctu
res
Introduction
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Every one of them:
Perform the mass budget (and preserves mass)
Make hypotheses on momentum variations
Simplify the energy conservation (and its dissipation)to a certain degree
(Implicitly delineates a way to entropy increase)
Introduction
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1. Radiation
4. surface energy balance
- radiation- boundary-layer interaction
2. Water balance
- effective rainfall- surface flow (runoff and channel routing)
- distributed model- sky view factor, self and cast shadowing, slope, aspect, drainage
3. Snow-glaciers
- multilayer snow scheme
- soil temperature- freezing soil
5. soil energy balance
- multi-layer vegetation scheme- evapotranspiration
6 . v e g e t a t i o n interaction
GEOtop structure
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Dunne Saturation Overland Flow
Unsaturated Layer
Surface Layer
Saturated Layer:
Horton Overland Flow
Modified from Abbot et al., 1986
All of it starts from a DEM
GEOtop structure
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
All of it starts from a DEM
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Layers, at the moment, form a structured grid.
With variable height.
The larger the height, the more uncoupled the layers.
On top there are dynamical snow layers
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
GEOtop structure
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
So, the overall grid is:
GEOtop structure
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Is that the best we can do ?
Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
GEOtop structure
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
Put vegetation on top !!!
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Arabba
Pordoi
Caprile
Malga Ciapela
Pescul
Ornella
Saviner
Places where John goes skiing!
GEOtop structure
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What do we put above the grid ?
Chapter 11
Vegetation
11.1 Vegetation
Figure 11.1: Precipitation
11.2 Input
11.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
VegHeight vegetation height mm 0,
20000
1000 sca num
continued on next page
43
GEOtop structure
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12. Surface Fluxes 12.2. Values of reference
Surface description z 0(cm) ReferenceMud flats, ice 0.001 Sutton (1953)Smooth tarmac 0.002 Bradley (1968)Large water surfaces 0.01 - 0.06 Numerous referencesGrass (lawn up to 1 cm) 0.1 Sutton (1953)Grass (artificial, 7.5 cm high) 1.0 Chamberlain (1966)Grass (thick up to 10 cm high) 2.3 Sutton (1953)Grass (thin up to 50 cm) 5 Sutton (1953)Trees (10-15 m high) 40-70 Fichtl and McVehil (1970)Large city 165 Yamamoto and Shimanuki (1964)
Table 12.9: Example of roughness parameters for various surfaces (Evaporation into the Atmosphere, Wilfried Brutsaert, 1984)
Figure 12.1: Water fluxes
page 54 of 92
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What do we put above the grid ?
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12.2. Values of reference 12. Surface Fluxes
Figure 12.2: Radiation
page 55 of 92
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GEOtop structure
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11. Vegetation 11.3. Output
Figure 11.2: Vegetation parameters
page 48 of 92
reflectivity
reflectivity
GEOtop structure
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12. Surface Fluxes 12.2. Values of reference
Figure 12.3: Energy Budget
page 56 of 92
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
What does the model do actually ?
Dynamic runoff
Dynamic energy and
mass budget
Dynamic snow or
Parametrizations of
radiation and turbulence
Boundary conditions
Boundary conditions
Blue are parametrizations Black are equations
Differentianl and other equations
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
What does the model do actually ?
Parametrizations of
radiation and turbulence
Dynamic runoff
Dynamic energy and
mass budget
Dynamic snow or
Boundary conditions
Dynamic Boundary conditions
GEOtop structure
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Chapter 3
Calculation domain
3.1 Domain Geometry1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05,
and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm].parameters→ parameters→ soil→ 1
name unit range of value default value# 1 Thickness mm 50
Table 3.1: Domain Geometry parameters
Figure 3.1: Soil thickness discretization
17
Chapter 10
Snow
10.1 Introduction
Figure 10.1: Snow stratigraphy
10.2 Input
10.2.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
ThresSnowSoilRough Threshold on snow depth to changeroughness to snow roughness valueswith d0 set at 0, for bare soil fraction
mm 0,1000
10 sca num
ThresSnowVegUp Threshold on snow depth abovewhich the roughness is snow rough-ness, for vegetation fraction
mm 0,20000
1000 sca num
ThresSnowVegDown Threshold on snow depth belowwhich the roughness is vegetationroughness, for vegetation fraction
mm 0,20000
1000 sca num
RoughElemXUnitArea Number of roughness elements(=vegetation) per unit area - usedonly for blowing snow subroutines
Numberm−2
0, inf 0 sca num
continued on next page
37
What does the model do actually ?
Parametrizations of
radiation and turbulence
Dynamic Boundary conditions Dynamic runoff
Dynamic energy and
mass budget
Boundary conditions
GEOtop structure
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Dynamic vegetation
GEOtop structure
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NOT YET BUT UPCOMING !
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Downloading
Chapter 1
Compiling Instructions
GEOtop runs properly under:
• Linux platform;
• Mac platform;
• Windows platform.
1.1 Compile GEOtop through a makefile
The GEOtop source code can be downloaded through a terminal (or command prompt if you are using Win-
dows) by typing, as shown in Figure 1.1:
”svn co https://dev.fsc.bz.it/repos/geotop/trunk/0.9375KMacKenzie”
Figure 1.1: Download GEOtop source code through a terminal
The downloaded folder contains the folders:
• Debug: which contains the object file created during the compilation and the makefile
• geotop: which contains the code
• Libraries: which contains the support libraries
Open a terminal, go into the folder Debug by typing:
$ cd Debug
3
GEOtop structure
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Running
1. Compiling Instructions 1.2. How to Run GEOtop
To compile GEOtop, type:
$ make all
The executable file GEOtop1.2 is now created in the Debug folder.
1.2 How to Run GEOtop1.2.1 From TerminalOpen a terminal, go into the folder Debug by typing:
$ cd Debug
Write:
$ ./GEOtop1.2
Leave one space and type now the path to the folder where the simulation files are:
$./GEOtop_1.2 /Users/matteo/Duron/
Remember to put a“/” (slash) at the end and the type Return. The simulation should start.
Figure 1.2: SVN
page 4 of 78
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6. Simulation flow-chart
Figure 6.1
page 24 of 92
GEOtop structure
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6. Simulation flow-chart
Figure 6.1
page 24 of 92
GEOtop structure
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Chapter 10
Surface Fluxes
10.1 Input
10.1.1 Parameters
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
SoilRoughness Roughness length of soil surface mm 0,1000
10 sca num
PointLandCoverType Land Cover type of the simulationpoint
- NA vec num
Table 10.1: Keywords of surface characteristics affecting surface energy fluxes
Keyword Description M. U. range Default
Value
Sca /
Vec
Str / Num
/ Opt
NumLandCoverTypes Number of Classes of land cover.Each land cover type corresponds to aparticular land-cover state, describedby a specific set of values of the pa-rameters listed below. Each set ofland cover parameters will be dis-tributively assigned according to theland cover map, which relates eachpixel with a land cover type num-ber. This number corresponds to thenumber of component in the numeri-cal vector that is assigned to any landcover parameters listed below.
- 1, inf 1 sca num
SoilAlbVisDry Ground surface albedo without snowin the visible - dry
- 0, 1 0.2 sca num
SoilAlbNIRDry Ground surface albedo without snowin the near infrared - dry
- 0, 1 0.2 sca num
SoilAlbVisWet Ground surface albedo without snowin the visible - saturated
- 0, 1 0.2 sca num
SoilAlbNIRWet Ground surface albedo without snowin the near infrared - saturated
- 0, 1 0.2 sca num
SoilEmissiv Ground surface emissivity - 0, 1 0.96 sca num
Table 10.2: Keywords of land cover characteristics affecting surface energy fluxes
41
Parameters: an excerpt from the dry manual
GEOtop structure
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14. Templates 14.2. 3D distributed simulation
- raster maps
- time series (discharge, air temperature, evaporation, latent heat fluxes, etc.....) at specific points (Figure 14.10).
The output raster maps (Figure 14.9) have to be specified by the user through appropriate keywords in the parameter file (see Table
14.9), in addition, their output frequency has to be assigned through the OutputXXXMaps parameter.
Figure 14.9: One of the many distributed output, the mean air temperature
page 74 of 78
Forcings where made spatial
GEOtop structure
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14.2. 3D distributed simulation 14. Templates
0.0 0.5 1.0 1.5 2.0
05
1015
2025
3035
Days
T [°C
]
Surface TemperatureAir Temperature
Figure 14.10: Two day-time series of mean air temperature output for a specified point
page 75 of 78
GEOtop structure
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Simulating is NOT the same as understanding
Simulating
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But understanding without modeling is difficult
Simulating
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In general before doing a simulation.Plan:
•Space and Time Resolutions
•Address subgrid variability
•Computational Burden
•Non calibrated parameters
•Calibration Strategy
•Model initialization•To carefully analyze the spatial characters of soil properties
•To carefully analyze the spatial time series of meteorological
data
Simulating
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In general before doing a simulation.
•Plan a validation strategy
•Make some null hypothesis
•Check the statistical structure of forcings and their correlation
In general after simulation.
•Always check mass and energy conservation
•Assess physical realism with quantitative objective tools in selected
points or transects.
•Compare spatial distributions of quantities, correlations, and patterns
(numbers of cluster of points above a threshold, size of above thresholds
islands, etc. )
http://abouthydrology.blogspot.com/search/label/Initial%20Conditions
Simulating
Wednesday, June 29, 2011
Hen
ry R
oss
eau
- T
he
dre
am, 1
92
0
The DreamAn example of fantastic realism (Dietrich et al. 200). Components
are realistic. The ecosystem is not. This is a methaphor of
inaccurate modeling.
Wednesday, June 29, 2011
Riccardo Rigon
Thank you for your attention.
G.U
lric
i -
20
00
?
47
Thanks, Thanks, Thanks
Wednesday, June 29, 2011