VIC Forcings Files
The VIC Classic Driver requires subdaily forcings (meteorological or other). Forcing timestep must be the same as snow model timestep, which is specified by the SNOW_STEPS_PER_DAY
parameter in the Global Parameter File. The required forcing variables and units are listed below and must also be specified in the Global Parameter File
Meteorological Forcings, Required in all simulations:
Variable |
Description |
Units |
AIR_TEMP |
Average air temperature |
C |
PREC |
Total precipitation (rain and snow) |
mm |
PRESSURE |
Atmospheric pressure |
kPa |
SWDOWN |
Incoming shortwave radiation |
W/m2 |
LWDOWN |
Incoming longwave radiation |
W/m2 |
VP |
Vapor pressure |
kPa |
WIND |
Wind speed |
m/s |
Vegetation Timeseries Forcings (Optional):
Variable |
Description |
Units |
ALBEDO |
Surface Albedo |
fraction (between 0 and 1) |
LAI |
Leaf Area Index |
m2/m2 |
FCANOPY |
Partial veg cover fraction ( = 1 - canopy gap fraction ) |
fraction (between 0 and 1) |
Lake Forcings, Required when LAKES is TRUE:
Variable |
Description |
Units |
CHANNEL_IN |
Incoming channel flow (total volume over the time step) |
m3 |
Carbon Cycle Forcings, Required when CARBON is TRUE:
Variable |
Description |
Units |
CATM |
Atmospheric CO2 mixing ratio |
ppm |
FDIR |
Fraction of incoming shortwave that is direct |
fraction |
PAR |
Photosynthetically active radiation |
W/m2 |
As of October 2015, work is currently underway to develop a next generation meteorological forcing generator. This work, in part, will support the development of VIC forcings. Follow or contribute to the development of these tools by visiting https://github.com/jhamman/mtclim5.