Improving the Performance of Temperature Index Snowmelt Model of SWAT by Using MODIS Land Surface Temperature Data
Table 7
Calibration parameters in Elev and New scenarios.
Parameters
Definition
Method
Range/percent
ALPHA_BF
Base-flow alpha factor (days)
V
0-1
CN2
Initial SCS CN II value
R
±50%
ESCO
Soil evaporation compensation factor
V
0.25–0.75
GW_DELAY
Groundwater delay (days)
V
0–30
SFTMP
Snowfall temperature (°C)
V
−5 to 5
SMTMP
Snowmelt base temperature (°C)
V
−5 to 5
SMFMN
Melt factor for snow on December 21 (mm H2O/°C-day)
V
0–3
SMFMX
Melt factor for snow on June 21 (mm H2O/°C-day)
V
3–9
SNO50COV
Fraction of snow volume represented by SNOCOVMX that corresponds to 50% snow cover
V
0.01–0.99
SNOCOVMX
Minimum snow water content corresponding to 100% snow cover (mm)
V
0–500
SOL_AWC
Average available water
R
±50%
SOL_K
Saturated conductivity
R
±50%
SURLAG
Surface runoff lag time (days)
V
1–24
TIMP
Snow pack temperature lag factor (°C)
V
0.01–1
TLAPS
Temperature lapse rate changed with the elevation (°C)
V
−10 to 0
Elev scenario is elevation bands combined with the original monitoring air temperature data scenario, and New scenario is the newly created air temperature data. V means the true value of the parameter and R means the relative range of the original parameter.
