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GEOtop: the making of               Henry Rosseau - The dream, 1920                                                 Riccar...
“Prediction is very difficult,                           especially about the future”                           Niels Bohr...
The GEOtop                                      Objectives     •To explain what GEOtop is;     •To explain why GEOtop is l...
The GEOtop                             Rainfall–Runoff spatial patterns       Problem:            We cannot currently pred...
The GEOtop                           Snowpack evolution and ablation          Problem: We would like to predict the spatia...
The GEOtop                           Landslide and debris flow initiation             Problem:         We cannot currently...
The GEOtop                                       Ecohydrology            Problem:       Well, I do not want to steal the w...
The GEOtop      However, hydrology in winter is usually different                            January                      ...
The GEOtop             In spring time plants have vegetative growth                                                       ...
The GEOtop                           In summer: land use matter                                                        10 ...
The GEOtop                           And eventually autumn comes                                                         1...
The GEOtop                    Committee of hydrological Sciences NRC, 2003:                            “Although our under...
Introduction                           Every Hydrologist would like to have                                  THE MODEL of ...
Introduction                           So we use different models                                                        1...
Introduction                                               So we use different models                           GEOtop    ...
IntroductionWednesday, June 29, 2011                           Riccardo Rigon                                             ...
IntroductionWednesday, June 29, 2011                           Riccardo Rigon                                             ...
IntroductionWednesday, June 29, 2011                           Riccardo Rigon                                             ...
Introduction                           Every one of them:                           Perform the mass budget (and preserves...
GEOtop structure                                          1. Radiation                                 - distributed model...
GEOtop structure                                 All of it starts from a DEM                                             H...
parameters → parameters → soil → 1GEOtop structure                                                  name         unit    r...
GEOtop structurehapter 10     Layers, at the moment, form a structured grid.now  With variable height.      The larger the...
GEOtop structure                           Chapter 3                           Calculationthe overall                     ...
GEOtop structure                           Chapter 3                            Is that the best                          ...
Chapter 3                               Put vegetation                           Calculation domain                       ...
GEOtop structure                           Places where John goes skiing!                                        Arabba   ...
GEOtop structure                 Vegetation                              What do we put above the grid ?                 1...
GEOtop structure                           What do we put above the grid ?                                     Figure 12.1...
GEOtop structure                                                    26                           Figure 12.2: Radiation Ri...
GEOtop structure                           27 Riccardo RigonWednesday, June 29, 2011
GEOtop structure                           reflectivity                                      reflectivity                 ...
GEOtop structure                                                        29                           Figure 12.3: Energy B...
Differentianl and other equations                            Chapter 3 does                            What               ...
GEOtop structure                             Chapter 3                           What doesdomain                          ...
GEOtop structure                             Chapter 3                           What doesdomain                          ...
GEOtop structure                           Dynamic vegetation                                                33 Riccardo R...
NOT YET BUT UPCOMING !                                                    34 Riccardo RigonWednesday, June 29, 2011
• Windows platform.GEOtop structure   1.1 Compile GEOtop through a makefile                           Downloading   The GEO...
1.2GEOtop structure                           How to Run GEOtop              1.2.1        From Terminal              Open ...
GEOtop structure                           37 Riccardo RigonWednesday, June 29, 2011
GEOtop structure                           Figure 6.1                                        38 Riccardo RigonWednesday, J...
GEOtop structure            Table 10.1: Keywords of surface characteristics affecting surface energy fluxes                ...
GEOtop- structure         raster maps          - time series (discharge, air temperature, evaporation, latent heat fluxes, ...
GEOtop structure                                    35                                    30                              ...
Simulating              Simulating is NOT the same as understanding                                                       ...
Simulating               But understanding without modeling is difficult                                                  ...
Simulating                              In general before doing a simulation.                                             ...
Simulating                           In general before doing a simulation.                  •Plan a validation strategy   ...
The Dream              An example of fantastic realism (Dietrich et al. 200). Components              are realistic. The e...
Thanks, Thanks, Thanks                                               Thank you for your attention.                        ...
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An introduction to the motivations that brought to build GEOtop

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Transcript of "1 geotop-summer-school2011"

  1. 1. GEOtop: the making of Henry Rosseau - The dream, 1920 Riccardo Rigon, Stefano Endrizzi, Matteo Dall’Amico, Stephan GruberWednesday, June 29, 2011
  2. 2. “Prediction is very difficult, especially about the future” Niels BohrWednesday, June 29, 2011
  3. 3. The GEOtop Objectives •To explain what GEOtop is; •To explain why GEOtop is like it is; •To enumerate the basic scheme and the basic equations 3 Riccardo RigonWednesday, June 29, 2011
  4. 4. The GEOtop Rainfall–Runoff spatial patterns 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. 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! 4 Riccardo RigonWednesday, June 29, 2011
  5. 5. The GEOtop Snowpack evolution and ablation 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 5 Riccardo RigonWednesday, June 29, 2011
  6. 6. The GEOtop Landslide and debris flow initiation 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. 6 Riccardo RigonWednesday, June 29, 2011
  7. 7. The GEOtop Ecohydrology Problem: Well, I do not want to steal the work to John and Kelly ;-) Critical Issue: See their lectures 7 Riccardo RigonWednesday, June 29, 2011
  8. 8. The GEOtop However, hydrology in winter is usually different January 8 Riccardo RigonWednesday, June 29, 2011
  9. 9. The GEOtop In spring time plants have vegetative growth 9 Riccardo RigonWednesday, June 29, 2011
  10. 10. The GEOtop In summer: land use matter 10 Riccardo RigonWednesday, June 29, 2011
  11. 11. The GEOtop And eventually autumn comes 11 Riccardo RigonWednesday, June 29, 2011
  12. 12. The GEOtop Committee of hydrological Sciences NRC, 2003: “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”. 12 Riccardo RigonWednesday, June 29, 2011
  13. 13. Introduction 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 13 Riccardo RigonWednesday, June 29, 2011
  14. 14. Introduction So we use different models 14 Riccardo RigonWednesday, June 29, 2011
  15. 15. Introduction So we use different models GEOtop Fully distributed Grid based 14 Riccardo RigonWednesday, June 29, 2011
  16. 16. IntroductionWednesday, June 29, 2011 Riccardo Rigon Fully distributed Grid based GEOtop Large scale modelling Hillslope - Stream Anthropic Infrastructures NewAge So we use different models 14
  17. 17. IntroductionWednesday, June 29, 2011 Riccardo Rigon Fully distributed Grid based GEOtop Large scale modelling Hillslope - Stream Anthropic Infrastructures NewAge Fully Coupled Subsurface- Surface Grid Based Boussinesq So we use different models 14
  18. 18. IntroductionWednesday, June 29, 2011 Riccardo Rigon Fully distributed Grid based GEOtop Large scale modelling Hillslope - Stream Anthropic Infrastructures NewAge Fully Coupled Subsurface- Surface Grid Based Boussinesq GIUH So we use different models Peak floods PeakFlow 14
  19. 19. Introduction 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) 15 Riccardo RigonWednesday, June 29, 2011
  20. 20. GEOtop structure 1. Radiation - distributed model - sky view factor, self and cast shadowing, slope, aspect, drainage 2. Water balance 6. vegetation interaction - effective rainfall - surface flow (runoff and channel - multi-layer vegetation routing) scheme - evapotranspiration 3. Snow-glaciers - multilayer snow scheme 5. soil energy balance - soil 4. surface energy balance temperature - freezing soil - radiation - boundary-layer interaction 16 Riccardo RigonWednesday, June 29, 2011
  21. 21. GEOtop structure All of it starts from a DEM Horton Overland Flow Dunne Saturation Overland Flow Surface Layer Unsaturated Layer Saturated Layer: Modified from Abbot et al., 1986 17 Riccardo RigonWednesday, June 29, 2011
  22. 22. parameters → parameters → soil → 1GEOtop structure name unit range of value default value #1 Thickness mm 50 All of it startsGeometry parameters DEM Table 3.1: Domain from a Figure 3.1: Soil thickness discretization 18 Riccardo RigonWednesday, June 29, 2011 17
  23. 23. GEOtop structurehapter 10 Layers, at the moment, form a structured grid.now With variable height. The larger the height, the more uncoupled the layers.1 Introduction are dynamical snow layers On top there Figure 10.1: Snow stratigraphy 19 Riccardo Rigon Wednesday, June 29, 2011
  24. 24. GEOtop structure Chapter 3 Calculationthe overall So, domain grid is: 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 10.1 Introduction name unit range of value default value #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Figure 10.1: Snow stratigraphy 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt ThresSnowSoilRough Threshold on snow depth to change mm 0, 10 sca num roughness to snow roughness values 1000 with d0 set at 0, for bare soil fraction ThresSnowVegUp Threshold on snow depth above mm 0, 1000 sca num which the roughness is snow rough- 20000 ness, for vegetation fraction ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Figure 3.1: Soil thickness discretization 20 Riccardo Rigon 17Wednesday, June 29, 2011
  25. 25. GEOtop structure Chapter 3 Is that the best Calculation domain we can do ? 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 10.1 Introduction name unit range of value default value #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Figure 10.1: Snow stratigraphy 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt ThresSnowSoilRough Threshold on snow depth to change mm 0, 10 sca num roughness to snow roughness values 1000 with d0 set at 0, for bare soil fraction ThresSnowVegUp Threshold on snow depth above mm 0, 1000 sca num which the roughness is snow rough- 20000 ness, for vegetation fraction ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Figure 3.1: Soil thickness discretization 21 Riccardo Rigon 17Wednesday, June 29, 2011
  26. 26. Chapter 3 Put vegetation Calculation domain on top !!! 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 10.1 Introduction name unit range of value default value #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Figure 10.1: Snow stratigraphy 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt ThresSnowSoilRough Threshold on snow depth to change mm 0, 10 sca num roughness to snow roughness values 1000 with d0 set at 0, for bare soil fraction ThresSnowVegUp Threshold on snow depth above mm 0, 1000 sca num which the roughness is snow rough- 20000 ness, for vegetation fraction ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Figure 3.1: Soil thickness discretization 22 Riccardo Rigon 17Wednesday, June 29, 2011
  27. 27. GEOtop structure Places where John goes skiing! Arabba Pordoi Ornella Saviner Pescul Caprile Malga Ciapela 23 Riccardo RigonWednesday, June 29, 2011
  28. 28. GEOtop structure Vegetation What do we put above the grid ? 11.1 Vegetation Figure 11.1: Precipitation 24 Riccardo Rigon 11.2 InputWednesday, June 29, 2011
  29. 29. GEOtop structure What do we put above the grid ? Figure 12.1: Water fluxes 25 Riccardo RigonWednesday, June 29, 2011
  30. 30. GEOtop structure 26 Figure 12.2: Radiation Riccardo RigonWednesday, June 29, 2011
  31. 31. GEOtop structure 27 Riccardo RigonWednesday, June 29, 2011
  32. 32. GEOtop structure reflectivity reflectivity Figure 11.2: Vegetation parameters 28 Riccardo RigonWednesday, June 29, 2011
  33. 33. GEOtop structure 29 Figure 12.3: Energy Budget Riccardo RigonWednesday, June 29, 2011
  34. 34. Differentianl and other equations Chapter 3 does What the model do actually ? Blue are parametrizations Calculation domain Black are equations 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 Parametrizations of 10.1 Introduction name unit range of value default value radiation and turbulence #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Dynamic snow or Boundary conditions Dynamic runoff Figure 10.1: Snow stratigraphy 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt Dynamic energy and ThresSnowSoilRough Threshold on snow depth to change mm 0, 10 sca num roughness to snow roughness values 1000 with d0 set at 0, for bare soil fraction ThresSnowVegUp Threshold on snow depth above mm 0, 1000 sca num which the roughness is snow rough- 20000 ness, for vegetation fraction mass budget ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Boundary conditions Figure 3.1: Soil thickness discretization 30 Riccardo RigonWednesday, June 29, 2011 17
  35. 35. GEOtop structure Chapter 3 What doesdomain Calculation the model do actually ? 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 Parametrizations of 10.1 Introduction name unit range of value default value radiation and turbulence #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Dynamic snow or Dynamic runoff Figure 10.1: Snow stratigraphy Dynamic Boundary conditions 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt Dynamic energy and ThresSnowSoilRough Threshold on snow depth to change mm 0, 10 sca num roughness to snow roughness values 1000 with d0 set at 0, for bare soil fraction ThresSnowVegUp Threshold on snow depth above mm 0, 1000 sca num which the roughness is snow rough- 20000 ness, for vegetation fraction mass budget ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Boundary conditions Figure 3.1: Soil thickness discretization 31 Riccardo Rigon 17Wednesday, June 29, 2011
  36. 36. GEOtop structure Chapter 3 What doesdomain Calculation the model do actually ? 3.1 Domain Geometry Chapter 10 1. Thickness: is the thickness of the layer; for numeric reasons it is advisable to settle the top layer with a thickness of 0.05, Snow and the first following with a thickness of 0.15m. Further layer thickness can be defined as wanted, [mm]. parameters → parameters → soil → 1 Parametrizations of 10.1 Introduction name unit range of value default value radiation and turbulence #1 Thickness mm 50 Table 3.1: Domain Geometry parameters Dynamic Boundary conditions Dynamic runoff Figure 10.1: Snow stratigraphy 10.2 Input 10.2.1 Parameters Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt ThresSnowSoilRough ThresSnowVegUp Threshold on snow depth to change mm roughness to snow roughness values with d0 set at 0, for bare soil fraction Threshold on snow depth above mm 0, 1000 0, 10 1000 sca sca num num Dynamic energy and which the roughness is snow rough- 20000 mass budget ness, for vegetation fraction ThresSnowVegDown Threshold on snow depth below mm 0, 1000 sca num which the roughness is vegetation 20000 roughness, for vegetation fraction RoughElemXUnitArea Number of roughness elements Number 0, inf 0 sca num (=vegetation) per unit area - used m−2 only for blowing snow subroutines continued on next page 37 Boundary conditions Figure 3.1: Soil thickness discretization 32 Riccardo Rigon 17Wednesday, June 29, 2011
  37. 37. GEOtop structure Dynamic vegetation 33 Riccardo RigonWednesday, June 29, 2011
  38. 38. NOT YET BUT UPCOMING ! 34 Riccardo RigonWednesday, June 29, 2011
  39. 39. • Windows platform.GEOtop structure 1.1 Compile GEOtop through a makefile Downloading The GEOtop source code can be downloaded through a terminal (or command prompt if you are using W 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 35 • Libraries: Riccardo Rigon which contains the support librariesWednesday, June 29, 2011
  40. 40. 1.2GEOtop structure How to Run GEOtop 1.2.1 From Terminal Open a terminal, go into the folder Debug by typing: Running $ 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 36 Riccardo RigonWednesday, June 29, 2011
  41. 41. GEOtop structure 37 Riccardo RigonWednesday, June 29, 2011
  42. 42. GEOtop structure Figure 6.1 38 Riccardo RigonWednesday, June 29, 2011
  43. 43. GEOtop structure Table 10.1: Keywords of surface characteristics affecting surface energy fluxes Parameters: an excerpt from the dry manual Keyword Description M. U. range Default Sca / Str / Num Value Vec / Opt NumLandCoverTypes Number of Classes of land cover. - 1, inf 1 sca num Each land cover type corresponds to a particular land-cover state, described by a specific set of values of the pa- rameters listed below. Each set of land cover parameters will be dis- tributively assigned according to the land cover map, which relates each pixel with a land cover type num- ber. This number corresponds to the number of component in the numeri- cal vector that is assigned to any land cover parameters listed below. SoilAlbVisDry Ground surface albedo without snow - 0, 1 0.2 sca num in the visible - dry SoilAlbNIRDry Ground surface albedo without snow - 0, 1 0.2 sca num in the near infrared - dry SoilAlbVisWet Ground surface albedo without snow - 0, 1 0.2 sca num in the visible - saturated SoilAlbNIRWet Ground surface albedo without snow - 0, 1 0.2 sca num in the near infrared - saturated SoilEmissiv Ground surface emissivity - 0, 1 0.96 sca num Table 10.2: Keywords of land cover characteristics affecting surface energy fluxes 39 Riccardo Rigon 41Wednesday, June 29, 2011
  44. 44. GEOtop- structure raster maps - time series (discharge, air temperature, evaporation, latent heat fluxes, etc.....) at specific points (Figure 14.10). Forcings where made spatial 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 40 Riccardo RigonWednesday, June 29, 2011
  45. 45. GEOtop structure 35 30 25 20 T [°C] 15 10 5 Surface Temperature Air Temperature 0 0.0 0.5 1.0 1.5 2.0 Days Figure 14.10: Two day-time series of mean air temperature output for a specified point 41 Riccardo RigonWednesday, June 29, 2011
  46. 46. Simulating Simulating is NOT the same as understanding 42 Riccardo RigonWednesday, June 29, 2011
  47. 47. Simulating But understanding without modeling is difficult 43 Riccardo RigonWednesday, June 29, 2011
  48. 48. Simulating 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 44 Riccardo RigonWednesday, June 29, 2011
  49. 49. Simulating 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 45 Riccardo RigonWednesday, June 29, 2011
  50. 50. The Dream An example of fantastic realism (Dietrich et al. 200). Components are realistic. The ecosystem is not. This is a methaphor of inaccurate modeling. Henry Rosseau - The dream, 1920Wednesday, June 29, 2011
  51. 51. Thanks, Thanks, Thanks Thank you for your attention. G.Ulrici - 2000 ? 47 Riccardo RigonWednesday, June 29, 2011
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