This file sets the irrigation options. It contains one namelist called
JULES_IRRIG namelist members¶
This namelist specifies the different options available for setting up the irrigation.
- Irrigation can be applied at a constant rate in three ways:
To apply a constant irrigation to all surface tiles the irrigation settings are as follows: frac_irrig_all_tiles=T, set_irrfrac_on_irrtiles=F and set a value for
To apply a constant irrigation to only specific surface tiles the irrigation settings are as follows: frac_irrig_all_tiles=F and set_irrfrac_on_irrtiles=T and set a value for
To apply a constant irrigation to specific surface tiles as an average across the gridbox, which is the way irrigation on specific tiles was done prior to vn5.7, the irrigation settings are as follows: frac_irrig_all_tiles=F, set_irrfrac_on_irrtiles=F and set a value for
In both option 2 and 3,
irrigtiles is the index of surface tiles you wish to irrigate, the length of which is
nirrtile e.g. if you include wheat and maize in your run at index 5 and 6 then irrigtiles=5,6 and nirrtile=2.
Switch controlling the implementation of irrigation demand code.
Tiles are irrigated.
This must be set to TRUE if
Switch controlling whether the amount of water used to irrigate tiles is limited.
Water for irrigation is taken first from the deep soil (groundwater) store, and then from the river storage when the deep soil store is exhausted. Tiles are irrigated up to the critical point if the necessary water is available. This option requires
l_rivers= TRUE and
The irrigation supply code in JULES is still in development, and is available in this release to support beta testing activities.
Users should ensure that results are as expected, and provide feedback where deficiencies are identified.
Tiles will be irrigated to critical point from an unconstrained water supply.
This must be set to FALSE if
0, 1 or 2
Irrigation season (i.e. season in which crops might be growing on the gridbox) lasts the entire year.
Irrigation season is determined from driving data according to Döll & Siebert (2002) method. No irrigation is applied outside the irrigation season.
Irrigation season is determined by maximum dvi across all surface tiles. Requires
ncpft> 0. No irrigation is applied outside the irrigation season.
If T, then irrigation fraction is applied to all surface tiles, and F, it is applied only to the surface tiles specified in
If F then irrigation is applied as an average across the gridbox and not to specific surface tiles. If T, then the irrigation fraction is only applied to the surface tile specified in
set_irrfrac_on_irrtilescannot be set to T.
The number of surface tiles to be irrigated. Only used if
Indices of the surface tiles to be irrigated. Only used if
The number of model timesteps per irrigation update step
Döll, P., and Siebert, S., Global modeling of irrigation water requirements, Water Resour. Res., 38(4), https://doi.org/10.1029/2001WR000355, 2002.