Temporal Event Control files

Tec File Instructions and Format

The TEC file is created in a text editor such as Notepad (NT) or VI (UNIX). Events in the TEC file must be listed in order of execution. Only one event per line is allowed. The format for events in the TEC file is as follows: Year month day hour eventYear month day hour event…Year month day hour event

Example: 1981 1 1 1 print_daily_on 1982 4 2 1 output_current_state 1982 4 3 1 redefine_strata 1984 12 30 1 print_daily_off

Save the TEC file.

TEC File Description

RHESSys is structured as an event driven simulation, where most of the process modeling occurs between events. RHESSys execution is based on a temporal event control or TEC file which must be specified in the command line. These events are used specify printing hourly, daily, monthly, yearly and state output options, redefinition of strata and road construction. The TEC file, as its name may imply, is not used to specify the modelling of certain processes as events.

RHESSys simulates daily and hourly routines between the events specified in the TEC file. At present, RHESSys performs most of its processes at a daily time step with the exception of climate simulation. Radiation estimation routines execute at an hourly timestep and then are summed to give daily radiation values. All other routines execute at a daily time step. The structure exists, however, for other hourly, monthly or yearly routines to be incorporated in the future. At present, there is a set of routines which execute at the beginning of the day, a set of routines which execute hourly and another set which execute at the end of the day.

RHESSys simulation begins at the start date and runs on a daily or hourly timestep (depending on the process being simulated). The simulation continues until a the next TEC event (e.g. print daily output) and then executes the TEC command. Once finished with the TEC command, RHESSys simulation continues until reaching either another TEC event or the end date. If there are no events specified in the TEC file, the simulation simply proceeds from the start date to the end date specified in the worldfile. No events in the TEC file is not normal operation. Simulation of a particular set of routines (i.e. start of the day, hourly and end of the day routines) is hierarchical. All world execution routines (e.g. world_daily_I - start of the day) call subroutines in their child containers (e.g. world_daily_I calls basin_daily_I which calls hillslope_daily_I,...,etc.) Temporal events refer to events which initiate a change or new processes in the simulation sequence. Events currently implemented are shown in Table 7 below. Numerous options can be specified and all options must be preceeded by the date (year month day hour) on which the event needs to occur.

TEC Event Options

TEC Event	Description
print_daily_on	Begin daily printing for regular or custom output*
print_daily_off	End daily printing for regular or custom output
print_daily_growth_on	Begin daily growth printing for regular output only
print_daily_growth_off	End daily growth printing for regular output only
print_yearly_on	Begin yearly printing for custom output only
print_yearly_off	End yearly printing for custom output only
print_monthly_on	Begin monthly printing for custom output only
print_monthly_off	End monthly printing for custom output only
print_hourly_on	Begin hourly printing for regular or custom output
print_hourly_off	End hourly printing for regular or custom output
print_daily_csv_on	Begin daily printing in comma delimited format for regular output only
print_daily_csv_off	End daily printing in comma delimited format for regular only
print_daily_csv_growth_on	Begin daily growth printing in comma delimited format for regular output only
print_daily_csv_growth_off	End daily growth printing in comma delimited for regular output only
roads_on	Begin road construction
roads_off	End road construction
redefine_world	Redefinition of the world
redefine_strata	Redefinition of strata (e.g. needed logging event)
output_current_state	Outputs current state in worldfile format

Important Notes

• The tec_file should not contain any blank lines. This will interfere with the parsing of the file and a run-time error may occur. Please make sure there are no blank lines, especially those at the end of the file.
• print_?_on and print_?_off control the flow of output in RHESSys. They will cause RHESSys to print data to the output files for specific levels in the hierarchy as chosen on the command line. These print options also control the temporal level of output data aggregation. That is, print_yearly_on will start the printing of yearly accumulated data.
• roads_on switches on routing of subsurface throughflow and overland flow via the road network. Prior to roads_on, roads are ignored in flow routing. Flow routing uses a flow_table to determine the pattern of flow across the landscape. Roads can potentially alter this pattern. When a road_on command is given; RHESSys reads in a new flow_table with a specific name. The name of the new "roads_on" flow_table must be the flow_table name that was specified on the command line appended by the date of the road event using the following format:

flow_table_name.YyearMmthDdayHhour e.g. if new road construction occurs Jan. 16, 1998 and the original flow_table is called flow_table.dat, RHESSys will search for the file called:

flow_table.dat.Y1998M1D16H1 The algorithms used for routing associated with a road network is described in Part II. roads_off switches the routing back to the initial flow_table.

• redefine_world and redefine_strata implements a user-controlled change to the landscape. This does not change the spatial containment hierarchy, it merely redefines strata types and the state of the world. That is, a land-use change such as logging is implemented in this way. redefine_strata and redefine_world assumes input of a stratum or worldstate definition file. For redefining the stratum, this file must be named by the worldfile name appended with str. Both files can also be generated using GRASS2WORLD.
• output_current_state outputs the current state of the simulation in a worldfile format and reflects the state of the world at the particular point in time. The resulting worldfile may then be used as input to another RHESSys simulation. When outputting the current state, RHESSys will call the new worldfile the same name as the worldfile specified in the simulation with a date extension of the date specified in the TEC file to output the current state, i.e. "hjaworld.Y1980M10D1H