ARC/INFO ASCII Grid Soil Parameter Files
The model first reads a file listing the names of all of the needed soil parameters. It then reads each soil parameter file and extracts the parameter value for the current grid cell.
Soil hydrologic and thermal parameters needed for the different VIC model set-ups are listed below. All input files must be available, but certain parameters need only be defined if the full energy or frozen soil models are activated. Red text indicates parameters needed for the energy balance model. Violet text indicates parameters needed for the frozen soil model. Header lines can be added by starting the line with a '#'.
Special utility programs and scripts are available for manipulating the parameters within the grid files.
File List File
File names must be in the order listed below, skipped or names out of order may not necessarily crash the model, but will yield incorrect results.
In version 4.0 average soil column parameters were replaced with average layer parameters. Soil parameter files for older versions of the model can be updated by using the average soil column parameter file for each soil moisture layer parameter.
| File Number | Parameter | Units | Description |
|
1 |
N/A |
Grid cell numbers |
|
|
2 |
run flag |
N/A |
Flag to indicate whether grid cell is run: 1 = run current cell |
|
3 |
dem |
m |
Grid cell elevation file |
|
4 |
N/A |
Variable infiltration curve parameter (binfilt) |
|
|
5 |
fraction |
Fraction of Dsmax where non-linear baseflow begins |
|
|
6 |
mm/day |
Maximum velocity of baseflow |
|
|
7 |
fraction |
Fraction of maximum soil moisture where non-linear baseflow occurs |
|
|
8 |
c |
N/A |
Exponent used in infiltration curve, normally set to 2 |
|
9 |
C |
Average soil temperature, used as the bottom boundary for soil heat flux solutions |
|
|
10 |
m |
Soil thermal damping depth (depth at which soil temperature remains constant through the year, ~4 m) |
|
|
11 |
off_gmt |
hours |
Time zone offset from GMT |
|
12:(Nlayer+11) |
fraction |
Fractional soil moisture content of each soil moisture layer at the critical point (~70% of field capacity) (fraction of maximum moisture). |
|
|
(Nlayer+12):(2*Nlayer+11) |
fraction |
Fractional soil moisture content of each soil moisture layer at the wilting point (fraction of maximum moisture) |
|
|
(2*Nlayer+12) |
m |
Surface roughness of bare soil |
|
|
(2*Nlayer+13) |
m |
Surface roughness of snowpack |
|
|
(2*Nlayer+14) |
mm |
Average annual precipitation |
|
|
(2*Nlayer+15): (3*Nlayer+14) |
percent |
Percent sand in the current layer. |
|
|
(3*Nlayer+15): (4*Nlayer+14) |
percent |
Percent clay in the current layer. |
|
|
(4*Nlayer+15): (5*Nlayer+14) |
mm/day |
Saturated hydraulic conductivity of the current layer. |
|
|
(5*Nlayer+15): (6*Nlayer+14) |
mm/mm |
Soil moisture diffusion coefficient. |
|
|
(6*Nlayer+15): (7*Nlayer+14) |
mm |
Initial moisture content of current layer. |
|
|
(7*Nlayer+15): (8*Nlayer+14) |
m |
Thickness of current layer. |
|
|
(8*Nlayer+15): (9*Nlayer+14) |
kg/m3 |
Bulk density of current layer. |
|
|
(9*Nlayer+15): (10*Nlayer+14) |
fraction |
Porosity of current layer. |
|
|
(10*Nlayer+15) |
fs_active |
1 or 0 |
If set to 1, then frozen soil algorithm is activated for the grid cell. A 0 indicates that frozen soils are not computed even if soil temperatures fall below 0C. |
Example Arc/Info Soil Parameter File:
############################################################################
### Example Arc/Info Soil Parameter File
### File is for the Illinois River within the Upper Mississippi Basin (upm),
### some parameters are down subdirectories for the current calibration run
### (ILL_CALIB17).
############################################################################
cellnum.upm
ill_run.asc
upm_dem.asc
ILL_CALIB17/b_infilt.upm
ILL_CALIB17/Ds.upm
Dsmax.upm
ILL_CALIB17/Ws.upm
c.upm
avg_temp.upm
dp.upm
off_gmt.upm
Wcr_fix.upm
Wcr_fix.upm
Wcr_fix.upm
Wpwp_fix.upm
Wpwp_fix.upm
Wpwp_fix.upm
rough.upm
snow_rough.upm
annual_prec.upm
annual_prec.upm
sand_l0.asc
sand_l1.asc
sand_l1.asc
clay_l0.asc
clay_l1.asc
clay_l1.asc
ILL_CALIB17/Ksat.asc
ILL_CALIB17/Ksat2.upm
ILL_CALIB17/Ksat2.upm
phi_s.upm
phi_s.upm
phi_s.upm
init_moist1.upm
init_moist2.upm
init_moist3.upm
ILL_CALIB17/depth1.upm
ILL_CALIB17/depth2.upm
ILL_CALIB17/depth3.upm
bulk_l0.asc
bulk_l1.asc
bulk_l1.asc
poro_l0.asc
poro_l1.asc
poro_l1.asc
fs_active.asc
##############################################################################
##Example ARC/INFO Gridded File:
##Cell number file for the Upper Mississippi
ncols 22
nrows 19
xllcorner -97.00
yllcorner 38.5
cellsize 0.50
NODATA_value -9999
-9999 -9999 -9999 1 2 3 4 5 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999
-9999 -9999 -9999 6 7 8 9 10 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999
-9999 -9999 11 12 13 14 15 16 17 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999
-9999 -9999 18 19 20 21 22 23 24 25 26 27 28 29 30 31 -9999 -9999 -9999 -9999 -9999 -9999
32 -9999 33 34 35 36 37 38 39 40 41 42 43 44 45 46 -9999 -9999 -9999 -9999 -9999 -9999
47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 -9999 -9999 -9999 -9999 -9999 -9999
63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 -9999 -9999 -9999 -9999 -9999 -9999
-9999 79 80 81 82 83 84 85 86 87 88 89 90 91 92 -9999 -9999 -9999 -9999 -9999 -9999 -9999
-9999 -9999 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 -9999 -9999 -9999 -9999 -9999
-9999 -9999 -9999 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 -9999 -9999 -9999 -9999
-9999 -9999 -9999 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 -9999 -9999 -9999 -9999
-9999 -9999 -9999 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 -9999 -9999 -9999 -9999
-9999 -9999 -9999 -9999 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 -9999 168 169
-9999 -9999 -9999 -9999 -9999 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 187 188 189 190 191 192 193 194 195 196 197 198 -9999 -9999
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 199 200 201 202 203 204 205 206 207 208 -9999 -9999 -9999 -9999
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 209 210 211 212 213 214 215 216 -9999 -9999 -9999 -9999 -9999
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 217 218 219 220 221 222 223 -9999 -9999 -9999 -9999 -9999 -9999
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 224 225 226 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999
VIC Administrator Last modified: Mon Aug 24 09:28:39 PDT 2009