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TUTORIAL
Exercise 1 | Exercise 2 | Exercise 3 | Exercise 4 | Exercise 5

Online Tutorial
Exercise 4, Preparing Input Files for Dynamic Simulations.

In this session, we introduce you to the following programs:

_soil - generate a soil table needed to run _dynamic
_climate - generate a climate file needed to run _dynamic
_chart - graphical interface used to display and evaluate time-series data
_rcoeff - generate a radiation coefficients table needed to run _dynamic
_simgen - grahical user interface used to control _dynamic simulations

4.1 Our initial dynamic simulations will be run on a 4 ha sub-catchment called sub. Let's study what the catchment looks like.
Perform the following tasks:

run _display, using basename sub.
plot the Element network.
map the distribution of the slope attribute to get a feel for the steepness of the catchment.
detect the number of contours and elements in the catchment.
quit _display.

4.1	Our initial dynamic simulations will be run on a 4 ha sub-catchment called sub. Let's study what the catchment looks like. Perform the following tasks: run _display, using basename sub. plot the Element network. map the distribution of the slope attribute to get a feel for the steepness of the catchment. detect the number of contours and elements in the catchment. quit _display.

4.2 We will begin with building up the soil properties for the catchment. Let's start by building a .nodes file; this specifies the depths at which soil water computations are made.
Perform the following tasks:

using the editor, build a file called sub1.nodes.
specify a 2 m deep, 2 layer soil profile that looks like this:

0 1 0.001 1 0.01 1 0.1 1 0.3 1 0.5 1 0.7 2 1.0 2 1.3 2 1.7 2 2.0 2

the first column is the solution node depth (in m), the second column is the soil type; note how the nodes are more closely spaced at the top of the profile.

4.3 Now, let's build some soil tables, using program _soil.
Perform the following tasks:

run _soil twice.
in each case, select option (1), Broadbridge and White.
use basenames of sub1 and sub2 for the first and second runs, respectively.
for each run, use the values tabulated below and default values elsewhere:

Parameter sub1 sub2

residual soil moisture content 0.05 0.05

saturated soil moisture content 0.50 0.40

saturated hydraulic conductivity 5.0 0.5

lc 0.1 0.1

C 1.3 1.10

Max. Dq 0.1 0.1

Driest y -400 -400

Number of points in table 200 200

using the editor, examine the contents of file sub1.soil.
note how the header contains all of the input values you used; the columns of data show the co-relations between q - y -K and record the derivatives of these.

4.4 Now, let's graphically display the contents of both soil tables; we can do this using program _chart.
Perform the following tasks:

run program _chart.
plot theta versus psi for sub1.soil (enter the file under the Other button).
press the Axes button and toggle the Y Log: option to -ve.
in the same window, plot the same curve for sub2.soil.
create a second pane and plot theta versus conductivity for both soil tables.
for clarity, toggle the Y Log: option to +ve.

4.4	Now, let's graphically display the contents of both soil tables; we can do this using program _chart. Perform the following tasks: run program _chart. plot theta versus psi for sub1.soil (enter the file under the Other button). press the Axes button and toggle the Y Log: option to -ve. in the same window, plot the same curve for sub2.soil. create a second pane and plot theta versus conductivity for both soil tables. for clarity, toggle the Y Log: option to +ve.

4.5 While we are at it, let's familiarise ourselves with some of the many functions of program _chart.
Perform the following tasks:

use the Cursor button to get the precise x and y values along the plotted lines.
change colours of the lines, using the Colours button.
display the legends, using the Annotate button.
change the legend text, using the Select button; select the item, delete the existing text using the backspace key, then enter your new text.
overlay the grid by pressing the Grid button twice.
zoom in and out.
change the plot style to Scatter plot.
annotate both plots using the Annotate button.
quit _chart.

4.5	While we are at it, let's familiarise ourselves with some of the many functions of program _chart. Perform the following tasks: use the Cursor button to get the precise x and y values along the plotted lines. change colours of the lines, using the Colours button. display the legends, using the Annotate button. change the legend text, using the Select button; select the item, delete the existing text using the backspace key, then enter your new text. overlay the grid by pressing the Grid button twice. zoom in and out. change the plot style to Scatter plot. annotate both plots using the Annotate button. quit _chart.

4.6 That does it for now with the soils information. Let's now turn to the necessary climate data inputs. We will begin by examining an existing .climate file.
Perform the following tasks:

using the editor, open file bspur.climate; this contains two-years worth of daily climate values from Blacks Spur near Healseville, Victoria.
note how it is a simple multi-column file with a header at the start; such data is routinely gathered by automatic weather stations these days.
run _chart, selecting file bspur.climate under the Files button.
plot Maximum and Minimum Temperature together in pane 1.
plot Vapour Pressure Deficit in pane 2.
plot Rainfall in pane 3 and Total Solar Radiation in pane 4.
show the legends for each data series.
use the Cursor button to obtain parameter values for any data series at any time instance.
use the Evaluate function to total and average values for the data series graphed in all four panes; set the lower bound to 500 and the upper bound to 700.

4.6	That does it for now with the soils information. Let's now turn to the necessary climate data inputs. We will begin by examining an existing .climate file. Perform the following tasks: using the editor, open file bspur.climate; this contains two-years worth of daily climate values from Blacks Spur near Healseville, Victoria. note how it is a simple multi-column file with a header at the start; such data is routinely gathered by automatic weather stations these days. run _chart, selecting file bspur.climate under the Files button. plot Maximum and Minimum Temperature together in pane 1. plot Vapour Pressure Deficit in pane 2. plot Rainfall in pane 3 and Total Solar Radiation in pane 4. show the legends for each data series. use the Cursor button to obtain parameter values for any data series at any time instance. use the Evaluate function to total and average values for the data series graphed in all four panes; set the lower bound to 500 and the upper bound to 700.

4.7 Whereas temperature and rainfall data are fairly common, radiation and vapour pressure deficit data are more difficult to come by. Using program _climate, these scarcer variables can be estimated empirically from the other data and written to a .climate file. Let's see how this is done.
Perform the following tasks:

using the editor, examine the contents of file junk.ppt; this is a typical raw climate file, containg tempearture and rainfall data but no radiation and vapour pressure information.
run _climate, using basename junk (this will access file junk.ppt).
use the following inputs and adopt default values elsewhere:

Start date: 01011972 Julian day entries? y Dew point temp. values?: n Total radiation data available? n Data site elevation: 350 Modelled site elevation: 600 Data site mean annual rainfall: 1300 Modelled site mean annual rainfall: 1600 Latitude: -35. Radiation attenuation file?: n

note how this program provides the facility for scaling temperature and rainfall data from one site to another; in the example we just ran, we modelled the climatic effects of increased elevation and isohyet.
using _chart, plot the rainfall column in junk.climate.
in the same pane, plot column 1 versus column 4 in junk.ppt; use the Evaluate button to determine the difference in total and average rainfall for the period day 150 to day 450; notice how the new rainfall is greater.
in a new pane, plot the maximum daily temperature from both data files and compare their values over the same time period; notice how the new temperature is lower.

4.8 The .climate file contains daily radiation values for a horizontal surface. We now need to build a (.rcoeff) file which will scale these values to surfaces with discrete slopes and aspects. This is done using program _rcoeff.
Perform the following tasks:

run program _rcoeff, using basename sub.
specify a latitude of -35.0.
note that the file has been written to sub.rcoeff.
using the editor, examine the contents of this file.

4.8	The .climate file contains daily radiation values for a horizontal surface. We now need to build a (.rcoeff) file which will scale these values to surfaces with discrete slopes and aspects. This is done using program _rcoeff. Perform the following tasks: run program _rcoeff, using basename sub. specify a latitude of -35.0. note that the file has been written to sub.rcoeff. using the editor, examine the contents of this file.

4.9 Now we turn to the vegetation inputs. The vegetation data requirements for the model vary significantly, depending on whether or not the plant growth module is invoked. To begin with, we will assume that the plant growth option is not being invoked.
Perform the following tasks:

using the editor, examine the contents of file sub1.veg; this is set for a single layer, uniformly distributed forest cover.
using the editor, examine the contents of file sub2.veg; this is set for a two layer, uniformly distributed forest cover.
using the editor, examine the contents of file sub3.veg; this is set for a two layer, spatially distributed forest cover (ie. 2 layers x 2 polygons)..

4.9	Now we turn to the vegetation inputs. The vegetation data requirements for the model vary significantly, depending on whether or not the plant growth module is invoked. To begin with, we will assume that the plant growth option is not being invoked. Perform the following tasks: using the editor, examine the contents of file sub1.veg; this is set for a single layer, uniformly distributed forest cover. using the editor, examine the contents of file sub2.veg; this is set for a two layer, uniformly distributed forest cover. using the editor, examine the contents of file sub3.veg; this is set for a two layer, spatially distributed forest cover (ie. 2 layers x 2 polygons)..

4.10 Now it's time to put all the data together in the simulation control or parameter (.par) file. This is done using program _simgen.
Perform the following tasks:

run _simgen.
fill the following fields with the following information:

basename sub

run identifier run1

start time 1

end time 730

climate files bspur.climate

radiation coefficients sub.rcoeff

soils files sub1.soil
sub2.soil

nodes file sub1.nodes

initial theta values 0.7
0.7

vegetation file sub1.veg

number of vegetation types 1

o/storey vegetation file index 1

o/storey LAI value 2.5

save to output parameter file sub.run1.par.
quit _simgen.
using the editor, view the contents of file sub.run1.par.

TUTORIAL
Exercise 1 | Exercise 2 | Exercise 3 | Exercise 4 | Exercise 5

last modified on 16 August 1997