Evaluation of a Land-surface
Model (Noah) for Semi-arid
Environments
Terri S. Hogue, Luis Bastidas, Hoshin Gupta,
and Soroosh Sorooshian
Study Sites
Lucky Hills (Desert Shrub)
Kendall (Grassland)
Precipitation Patterns
Precipitation Stats
Precipitation Totals (mm)
Kendall
LHills
4 year avg
372
480
1997
333
495
1998
365
338
1999
337
439
2000
451
649
1997 MON
151 (45%)
241 (49%)
1998 MON
250 (68%)
197 (58%)
1999 MON
315 (93%)
412 (94%)
2000 MON
158 (35%)
282 (43%)
1997/98 WIN
132
171
1998/99 WIN
9.2
9.9
1999/00 WIN
6.1
12.4
Testing Schemes
Split Sample
Validation Period
Calibration Period 1997-2000 1997
1998
1999
2000 1997-1998 1999-2000
1998,99,00
1997,99,00
1997,98,00 1997,98,99
1997-2000
1997
1998
1999
2000
1997-1998
1999-2000
calibration
validation
Proxy Basin
Calibration
1997-00
1997
1998
1999
2000
1997-98
1999-00
MON1997-00
MON1997-00
MON1999
WIN1997-98
1997-00
1997
1998
Validation Period (Proxy Basin)
1999
2000 1997-98
1998-99 MON1997-00
WIN1997-00 MON11999WIN1997-98
Objective Functions
Objective Function s
Objective Function s
Kendall Objective Functions
Normalized Values (to 1997-00)
Kendall Split Sample Results
Proxy-Basin Results – Kendall w/LHills
Differential Split Sample
Validation Period (Proxy Basin for PB-DSS)
Calibration Period MON1997-00 WIN1997-00
MON1999
WIN1997-98
1997-00
1997
1998
1999
2000
MON1997-00
WIN1997-00
MON1999
WIN1997-98
X
X
Differential Split Sample Results
Kendall - Sensible Heat
Lucky Hills - Sensible Heat
DEF
1997-00
90.00
80.00
1997
80.00
70.00
1998
70.00
1998
60.00
1999
60.00
1999
50.00
2000
50.00
2000
40.00
mon97-00
40.00
mon97-00
30.00
win97-00
30.00
win97-00
20.00
mon99
20.00
mon99
10.00
EN97-98
10.00
EN97-09
RMS Errors
RMS Errors
DEF
90.00
0.00
1997-00
1997
0.00
mon97-00
win97-00
mon99
EN97-98
mon97-00
Validation Period
mon99
EN97-98
Validation Period
Kendall - Latent Heat
Lucky Hills - Latent Heat
DEF
DEF
110.00
90.00
1997
80.00
1998
70.00
1999
60.00
2000
50.00
mon97-00
40.00
win97-00
30.00
mon99
20.00
EN97-98
10.00
RMS Errors
1997-00
100.00
RMS Errors
win97-00
110
1997-00
100
1997
90
1998
80
1999
70
2000
60
mon97-00
50
40
win97-00
30
mon99
20
EN97-98
10
0.00
0
mon97-00
win97-00
mon99
Validation Period
EN97-98
mon97-00
win97-00
mon99
Validation Period
EN97-98
Kendall – 10-day monsoon period (1997-00 pars)
OBSERVED
Sensible Heat
W/m2
DEFAULT
Latent Heat
W/m2
Ground Heat
W/m2
Ground Temp
CALIBRATED
°C
Kendall – 10-day monsoon period (1999 pars)
OBSERVED
Sensible Heat
W/m2
Latent Heat
W/m2
Ground Heat
W/m2
Ground Temp
CALIBRATED
DEFAULT
°C
Preliminary Conclusions
The developed methods provide a rigorous framework for comparisons of
the behavior of land-surface models across various biomes:
• Parameter sets from nearly all calibration periods show improved
performance over default simulations
• Longer calibration-period parameter sets do not capture seasonal
/annual variability
• There is a need for both “wet” and “dry” periods. The increase in
latent heat during short climatic events is not modeled well.
• Proxy site parameters results in similar performance for most periods
Differential Split Sample Results
Lucky Hills Split Sample Results
Objective Functions
Objective Function s
Objective Function s
Lucky Hills Objective Functions
Normalized Values (to 1997-00)