16. Raster exporting#
This file is used to write raster of variables computed by the FeST.
The file contains a list of keywords, one for each variable the user can export.
The keyword time set times when raster maps are written to output in folder
specified by folder keyword. The section [map-template] (optional)
allows to re-mapping raster maps to a given map template before
files are written to output folder. This allows to change map
extent, spatial resolution or spatial reference system. (see example below).
Example of raster-export configuration file
# configure variables for raster export
time = 0 0,12 * * *
folder = ./results/raster_maps/
[map-template]
file = ./data/template_wgs84.asc
format = esri-ascii
epsg = 4326
[soil-balance]
soil-moisture = 0
runoff = 0
infiltration = 0
percolation = 0
actual-ET = 0
potential-ET = 0
[meteo]
precipitation = 1
temperature = 1
relative-humidity = 0
solar-radiation = 0
net-radiation = 0
wind-speed = 0
[snow]
snow-water-equivalent = 0
The raster map is computed and written to output folder for all variables marked with 1.
When one variable is marked by 1 but it is not allocated because not computed by
the FeST model according to options defined in the configuration files,
file is not exported. For example, if user set to export wind-speed but
windspeed is not used in the current simulation, map of windspeed is
not written to output folder. Currently maps are exported in esri-ascii format,
one map for each variable and for each time step. Raster maps are
processed before being written to output file in order to compute
the average value or the cumulated value between to time steps,
according to the specific variable (see table below).
Exporting time steps are assigned with a string that mimics the cron-table syntax on Linux operating systems, a configuration file that specifies shell commands to run periodically on a given schedule.
The syntax expects a string made of five fields which represent the time to write files to output folder, as described below:
Description of the string to configure time to export maps.
┌───────────── minute (0–59)
│ ┌───────────── hour (0–23)
│ │ ┌───────────── day of the month (1–31)
│ │ │ ┌───────────── month (1–12)
│ │ │ │ ┌───────────── day of the week (0–6) (Sunday to Saturday)
│ │ │ │ │
│ │ │ │ │
│ │ │ │ │
* * * * *
Some examples:
0 * * * * once an hour at the beginning of the hour
0 0 * * * once a day at midnight
0 0 * * 0 once a week at midnight on Sunday
0 0 1 * * once a month at midnight of the first day of the month
0 0 1 1 * once a year at midnight of 1 January
Specifying multiple specific time intervals can be done with commas (e.g., 1,2,3)
or with hyphen to assign a range of values (e.g. 7-10).
Variables that can be exported, description, and unit are listed in the following table.
variable |
Description |
Unit |
|---|---|---|
precipitation |
Precipitation fallen in the time step (cumulated) |
mm |
temperature |
Air temperature (average) |
Celsius degree |
relative-humidity |
Air relative humidity (average) |
% (0-100) |
solar-radiation |
Solar radiation (average) |
w/m² |
net-radiation |
Net radiation (average) |
w/m² |
wind-speed |
Wind speed (average) |
m/s |
snow-water-equivalent |
Snow water equivalent (average) |
mm |
soil-moisture |
Soil moisture (average) |
- |
runoff |
Runoff (cumulated) |
mm |
infiltration |
Infiltration (cumulated) |
mm |
percolation |
Deep percolation out of transmission zone (cumulated) |
mm |
actual-ET |
Actual evapotranspiration (cumulated) |
mm |
potential-ET |
Potential evapotranspiration (cumulated) |
mm |
The name of output files is the concatenation of folder name defined
in the configuration file <folder>, a suffix in the form YYYY-MM-DDThh-mm
that reminds date and time of the current time step <time>, and a suffix
that reminds the name of variable, as listed in the following table.
variable |
Output file name |
|---|---|
precipitation |
|
temperature |
|
relative-humidity |
|
solar-radiation |
|
net-radiation |
|
wind-speed |
|
snow-water-equivalent |
|
soil-moisture |
|
runoff |
|
infiltration |
|
percolation |
|
actual-ET |
|
potential-ET |
|