This document describes the procedure for generating VIC parameters for projected future land cover change. This procedure assumes we have started with a set of land cover maps corresponding to at least one historical map and at least one future projection using the same classification scheme. The historical map should be used to generate historical VIC parameters via the "NLCD_INEGI" version of the main procedure.
The future parameters are then generated by (1) aggregating the future land cover map (ascii-format ESRI grid file) to area fractions at the desired resolution; (2) replacing the Cv
variable in the historical VIC parameter file with the area fractions from step (1); and (3) filling gaps in the parameters (cells for which classes have appeared in the future that did not exist there in the historical map) by spatially interpolating the parameters for those classes from neighboring cells.
This step aggregates a land cover map (ascii-format ESRI grid file) to area fractions at the desired resolution, in NetCDF format. The area fractions are stored in a variable named Cv
. Run the following script:
aggregate_lc_map.py -d $DOMAIN_FILE -m $LC_MAP_FILE -t $LC_TABLE -o $OUTFILE
where
$DOMAIN_FILE
= VIC-5-image-mode-compliant domain file (NetCDF)
$LC_MAP_FILE
= ESRI ascii-format land cover map
$LC_TABLE
= Ascii comma-separated-value (csv) file listing the land cover classes, and their names, similar to ../data/USMX/lc_table.USMX.NLCD_INEGI.csv
$OUTFILE
= output path/filename
This step replaces the Cv
variable of a historical VIC parameter file with the Cv
variable generated in step 1. Run the following script:
replace_cv.py -i $INFILE -c $CV_FILE -o $OUTFILE
where
$INFILE
= VIC-5-image-mode-compliant historical parameter file
$CV_FILE
= NetCDF file containing new Cv
variable, created in step 1
$OUTFILE
= output path/filename (this will be the historical VIC parameters but with the future Cv
)
This step fills gaps in the parameters (arising from classes appearing in cells where no parameters exist for them) by spatial interpolation from neghboring cells. Run the following script:
gapfill_vic_params.py -i $INFILE [-a] [-r] [-m] -o $OUTFILE
where
$INFILE
= modified VIC parameter file created in step 2
-a
= optional flag specifying that a max_snow_albedo
variable is present
-r
= optional flag specifying that irrigation variables are present
-m
= optional flag specifying that impervious area fraction variables are present
$OUTFILE
= output path/filename for gap-filled parameters
NOTE: the -r
and -m
options are only applicable to the feature/irrig.imperv.deep_esoil
branch of the tbohn/VIC
fork of the UW-Hydro/VIC
GitHub repo, available at https://github.com/tbohn/VIC/tree/feature/irrig.imperv.deep_esoil.