JULES only supports the use of ASCII files for data at a single location. In this case, the input grid can be specified either as a 1D grid with length 1 or as a 2D grid of size 1 x 1. The data should be laid out in columns with one timestep of data per row (with time increasing with the number of rows). For variables with an additional dimension (e.g. soil layers), the values for each level should be in consecutive columns.
Variables should be given to JULES in the order they appear in the file, and there should be no unused variables in between. This may mean that some datasets may require pre-processing for use with JULES, even if they are already columnar.
If the first character of a line is either # or !, the line is taken to be a comment. JULES reads no information from comments - they are purely for annotating the dataset for users.
This example is taken from the Loobos data in loobos/Loobos_1997.dat:
# Meteorological data for Loobos, 1997.
# One year of 30 minute data.
# Down Down Rainfall Snowfall Air Wind Specific
# SWR LWR rate rate temp. speed Pressure humidity
#(W m-2) (W m-2) (kg m-2 s-1) (kg m-2 s-1) (K) (m s-1) ) (Pa) (kg kg-1)
0.0 187.8 0.000E+00 0.000E+00 259.800 2.017 102400.0 1.384E-03
0.0 186.9 0.000E+00 0.000E+00 259.700 3.770 102400.0 1.384E-03
0.0 186.7 0.000E+00 0.000E+00 259.600 4.290 102400.0 1.373E-03
# ...
Each row represents a timestep of data. Each column represents a variable. Driving variables have no additional dimension.
From the Loobos example - see examples/point_loobos/data/initial_conditions.dat:
# sthuf(1:sm_levels) t_soil(1:sm_levels)
0.749 0.743 0.754 0.759 276.78 277.46 278.99 282.48
Although only one ‘timestep’ of data is supplied, the data must still be laid out in columns. These variables have a value for each soil layer, which are given in consecutive columns. This quickly becomes cumbersome for large numbers of variables, which is why NetCDF is recommended even for data at a single point.
# lai(1:npft) canht(1:npft)
0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.6 0.0 0.0
0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.6 0.0 0.0
0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.7 0.0 0.0
# ...
These variables have one value for each plant functional type (see Overview of JULES). For each variable, the values for each pft are in consecutive columns. Each row is one timestep of data.