Development of a 3-D Hydrodynamic Model for Lake Sammamish
Curtis DeGasperiKing County DNRP, WLRD
Science SeminarNovember 23, 2004
King County’s Freshwater Program (formerly SWAMP and GDWQA)
Lakes Background -Washington
Metric EnglishDrainage Basin Area 1,274 km2 314,800 acCedar Basin 495 km2 122,300 acLake Surface Area 87.6 km2 21,500 acLake Volume 2.9x109 m3 2.35x106 ac-ftMean Depth 33 m 108 ftMaximum Depth 65.2 m 214 ft
Mean Residence Time 2.3 years
Lakes Background -Sammamish
Metric EnglishDrainage Basin Area 230 km2 57,000 acIssaquah Basin 145 km2 35,600 acLake Surface Area 19.8 km2 4,900 acLake Volume 3.5x108 m3 283,860 ac-ftMean Depth 17.7 m 58 ftMaximum Depth 32 m 105 ft
Mean Residence Time 1.8 years
LakesCH3DCE-QUAL-ICM
RiverCE-QUAL-W2
WatershedHSPFUrbanSim
Model Selection
Lake Models Background
• Initially developed for Chesapeake Bay• ACOE-ERDC set up and calibrate Lake
Washington models• King County set up and calibrate Lake
Sammamish models
CH3D Model
• 3-D model• Temperature• Salinity• Horizontal and vertical velocity
ACOE-ERDC Lake WashingtonCH3D Model• Boundary fitted z-coordinate grid• k-ε turbulence closure scheme (Rodi 1980)• Heat exchange confined to surface layer• Externally processed Equilibrium
Temperature (ET) heat exchange• Solar radiation calculated in ET program• Simple convective vertical mixing scheme
Temperature Modeling
Solar shortwave radiation
Atmoshpericlongwaveradiation
Conduction and
Convection
Longwaveback radiation
from water
Evaporation and
condenstation
Radiation terms Non-radiation terms
Net absorbed radiation Water dependent terms
Hn = Hs + Ha + He + Hc - (Hsr + Har + Hbr)
Equilibrium Temperature
• Conceptually simple• Computation may be performed externally• Closed-form analytical solution• Assumes heat loss is linearly related to
water temperature
James Martin and Steven McCutcheon. 1999. Hydrodynamics and Transport for Water Quality Modeling. page 372.
)( eTwTawKawH −−=
Model Setup
• Bathymetry• Meteorology• Constituent Inputs (trib/precip)
Data Sources
• Bathymetry (JC Headwaters/King County)• Meteorology (Sea-Tac/Sand Point)• Hydrology and stream temperature (WLRD,
USGS)• Water quality data (WLRD)• Lake water surface elevations (USGS/ACOE)
Bathymetry
4,283 cells
249 surface cells
30 layers
layers 3 feet (0.91 m) thick
Average cell area 0.08 km2
(19.8 ac)
Average cell length 280 m (920 ft)
Lake Sammamish Grid
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UW Atm Sci
WSDOT SR520
WSDOT I-90
Boeing Field
Sea-Tac
RUSS-SAMMS
Lake Washington
Lake Sammamish
Renton Airport
NOAA-ISIS
Meteorological Data Sources
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Boeing Field
Sea-Tac
Lake Washington
Lake Sammamish
Meteorological Data Sources
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Lake Washington
Lake SammamishUW Atm Sci
NOAA-ISIS
Meteorological Data Sources
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Lake Washington
Lake Sammamish
RUSS-SAMMS
Meteorological Data Sources
Wind Speed ScalingWIND SPEED ADJUSTMENT
0
2
4
6
8
10
12
14
16
0 2 4 6 8
WIND SPEED (M S-1)
OB
S H
EIG
HT
(M)
Adjusted SpeedObs Height:
Observation Height6.1 m
P
zzUU ⎟⎠⎞
⎜⎝⎛=
1
212
Wind Speed ScalingWIND SPEED ADJUSTMENT
0
2
4
6
8
10
12
14
16
0 2 4 6 8
WIND SPEED (M S-1)
OB
S H
EIG
HT
(M)
Adjusted SpeedObs Height:
Observation Height6.1 m )(12 WSFUU =
Wind Adjustment Factor (WAF)
Surface Shear Stress
U10m = U6.1m x WSF x WAF
Surface Heat Exchange
U2m = U6.1m x WSF x WAF
Monthly Average Wind Speed ComparisonRUSS vs Sea-Tac
0
1
2
3
4
5
1/1/2000 12/31/2000 12/31/2001 12/31/2002 1/1/2004
Date
M S
-1
RUSS Sea-Tac
Sea-Tac
RUSS
RUSS Monthly Average Wind Speed - % of Sea-Tac
0
20
40
60
80
100
120
1/1/2000 12/31/2000 12/31/2001 12/31/2002 1/1/2004
Date
Perc
ent
Wind Speed at Lake Averages ~90 % of Sea-Tac Wind
Sea-Tac Hourly Wind Speed by Year
YEAR
1995 1996 1997 1998 1999 2000 2001 2002
M S
-1
0
5
10
15
20
Wind Data EvaluationSEA-TAC
ASOS Oct. 1996
Wind Data EvaluationBoeing Field
Year
1995 1996 1997 1998 1999 2000 2001 2002
M S
-1
0
5
10
15
20
BOEING FIELD
ASOS Dec. 1998
Model Calibration1995 - 2002
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0625
0611
0622
M621
0612
0617
0614
CH3D Temperature Results1995 - 2002
CH3D 1995 - 0612
0 10 20
0
5
10
15
20
25
30bias =0.0881ame =0.0881rmse =0.0882
17-Jan-1995CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.16ame =0.186rmse =0.224
08-Feb-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.326ame =0.326rmse =0.384
07-Mar-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.166ame =0.297rmse =0.387
04-Apr-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.331ame =0.355rmse =0.52
18-Apr-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.329ame =0.363rmse =0.482
02-May-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.132ame =0.28rmse =0.334
16-May-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.714ame =0.863rmse =1.26
05-Jun-1995
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.44ame =0.481rmse =0.703
10-Jul-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.225ame =0.341rmse =0.557
01-Aug-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.312ame =0.75rmse =0.907
12-Sep-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.279ame =0.813rmse =0.899
02-Oct-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0838ame =0.391rmse =0.43
09-Nov-1995
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0827ame =0.122rmse =0.163
05-Dec-1995
Temperature (oC)
CH3D 1996 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.249ame =0.249rmse =0.25
03-Jan-1996CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.0922ame =0.0929rmse =0.104
07-Feb-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.568ame =0.568rmse =0.581
06-Mar-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.586ame =0.602rmse =0.704
21-Mar-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.21ame =1.21rmse =1.27
10-Apr-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.429ame =0.493rmse =0.558
30-Apr-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.541ame =0.541rmse =0.582
08-May-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.354ame =0.671rmse =0.965
21-May-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.0832ame =0.615rmse =0.769
04-Jun-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.254ame =0.606rmse =0.895
18-Jun-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.36ame =0.714rmse =1.05
02-Jul-1996
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.425ame =0.905rmse =1.03
24-Jul-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.143ame =0.703rmse =0.742
06-Aug-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0376ame =0.777rmse =0.879
21-Aug-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0138ame =0.521rmse =0.724
05-Sep-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.547ame =0.716rmse =0.945
17-Sep-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.543ame =0.781rmse =1.01
01-Oct-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.93ame =0.93rmse =1.03
06-Nov-1996
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.113ame =0.186rmse =0.2
04-Dec-1996
Temperature (oC)
CH3D 1997 - 0612
0 10 20
0
5
10
15
20
25
30bias =0.148ame =0.151rmse =0.234
22-Jan-1997CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.1ame =0.111rmse =0.117
05-Feb-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.138ame =0.138rmse =0.143
03-Mar-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0517ame =0.133rmse =0.141
02-Apr-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30
23-Apr-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0818ame =0.319rmse =0.38
07-May-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.75ame =0.775rmse =1.13
02-Jun-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =NaName =NaNrmse =NaN
02-Jul-1997
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.164ame =0.525rmse =0.665
06-Aug-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.503ame =0.88rmse =1.05
02-Sep-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.06ame =1.06rmse =1.31
01-Oct-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.63ame =0.63rmse =0.751
08-Oct-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0878ame =0.205rmse =0.244
05-Nov-1997
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.18ame =0.18rmse =0.18
03-Dec-1997
Temperature (oC)
CH3D 1998 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.506ame =0.506rmse =0.507
07-Jan-1998CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.675ame =0.675rmse =0.675
03-Feb-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.935ame =0.935rmse =0.938
03-Mar-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.457ame =0.496rmse =0.607
24-Mar-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.701ame =0.701rmse =0.817
06-Apr-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.601ame =0.608rmse =0.829
21-Apr-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.478ame =0.562rmse =0.886
05-May-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.917ame =1.02rmse =1.22
03-Jun-1998
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.485ame =0.585rmse =0.939
06-Jul-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.643ame =0.899rmse =1.27
05-Aug-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0567ame =0.843rmse =1.01
08-Sep-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.08ame =1.29rmse =1.61
07-Oct-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.11ame =1.32rmse =1.62
02-Nov-1998
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.196ame =0.196rmse =0.209
14-Dec-1998
Temperature (oC)
CH3D 1999 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.069ame =0.069rmse =0.0875
05-Jan-1999CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.856ame =0.856rmse =0.856
03-Feb-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-1.02ame =1.02rmse =1.02
02-Mar-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.512ame =0.512rmse =0.536
23-Mar-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.303ame =0.303rmse =0.418
06-Apr-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.369ame =0.54rmse =0.769
19-Apr-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0397ame =0.496rmse =0.591
05-May-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.287ame =0.428rmse =0.528
24-May-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.298ame =0.368rmse =0.443
08-Jun-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.842ame =0.968rmse =1.28
07-Jul-1999
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =NaName =NaNrmse =NaN
20-Jul-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.762ame =0.822rmse =1.07
03-Aug-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =NaName =NaNrmse =NaN
17-Aug-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.55ame =0.811rmse =1.15
08-Sep-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.06ame =0.489rmse =0.564
21-Sep-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.428ame =0.844rmse =0.998
05-Oct-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.51ame =0.525rmse =0.865
02-Nov-1999
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =NaName =NaNrmse =NaN
07-Dec-1999
Temperature (oC)
CH3D 2000 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.848ame =0.848rmse =0.848
05-Jan-2000CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.735ame =0.735rmse =0.757
08-Feb-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.637ame =0.637rmse =0.644
07-Mar-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.824ame =0.824rmse =0.837
21-Mar-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.873ame =0.873rmse =1.12
04-Apr-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.499ame =0.592rmse =0.711
02-May-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.528ame =0.589rmse =0.822
16-May-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-1.03ame =1.07rmse =1.37
13-Jun-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.57ame =0.67rmse =0.888
05-Jul-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.809ame =0.917rmse =1.55
18-Jul-2000
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.85ame =0.876rmse =1.16
08-Aug-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =NaName =NaNrmse =NaN
22-Aug-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.337ame =0.52rmse =0.669
06-Sep-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.579ame =0.887rmse =1.01
19-Sep-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.487ame =1.01rmse =1.23
03-Oct-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.765ame =1.26rmse =1.45
31-Oct-2000
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.0978ame =0.0978rmse =0.134
04-Dec-2000
Temperature (oC)
CH3D 2001 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.309ame =0.309rmse =0.309
03-Jan-2001CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.576ame =0.576rmse =0.576
31-Jan-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.442ame =0.442rmse =0.502
27-Feb-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.265ame =0.265rmse =0.288
20-Mar-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.589ame =0.589rmse =0.66
03-Apr-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.484ame =0.522rmse =0.629
17-Apr-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.327ame =0.359rmse =0.459
02-May-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.383ame =0.532rmse =0.657
21-May-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.143ame =0.409rmse =0.479
30-May-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.527ame =0.68rmse =0.806
19-Jun-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.682ame =0.804rmse =1.04
02-Jul-2001
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.577ame =0.68rmse =0.911
17-Jul-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.02ame =0.213rmse =0.286
07-Aug-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.85ame =0.951rmse =1.34
21-Aug-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.646ame =0.898rmse =1.46
05-Sep-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.261ame =0.684rmse =0.788
18-Sep-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.37ame =0.922rmse =0.975
02-Oct-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.394ame =0.748rmse =0.838
06-Nov-2001
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.414ame =0.414rmse =0.414
03-Dec-2001
Temperature (oC)
CH3D 2002 - 0612
0 10 20
0
5
10
15
20
25
30bias =-0.616ame =0.616rmse =0.621
09-Jan-2002CH3D 0612
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.691ame =0.691rmse =0.691
28-Jan-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.539ame =0.539rmse =0.551
05-Mar-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.586ame =0.586rmse =0.586
18-Mar-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.636ame =0.636rmse =0.942
02-Apr-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.196ame =0.475rmse =0.497
17-Apr-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0592ame =0.337rmse =0.411
07-May-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.636ame =0.94rmse =1.34
21-May-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.462ame =0.847rmse =1.32
04-Jun-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.689ame =0.89rmse =1.28
18-Jun-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.00681ame =0.766rmse =0.845
01-Jul-2002
Dep
th (m
)
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.37ame =1.25rmse =1.5
16-Jul-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.47ame =0.977rmse =1.07
07-Aug-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =-0.0861ame =1.38rmse =1.56
19-Aug-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.373ame =1.33rmse =1.43
04-Sep-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.22ame =1.36rmse =1.62
17-Sep-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.787ame =1.42rmse =1.66
07-Oct-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =1.56ame =1.63rmse =1.96
04-Nov-2002
Temperature (oC)
0 10 20
0
5
10
15
20
25
30bias =0.433ame =0.433rmse =0.644
03-Dec-2002
Temperature (oC)
Model Error Statistics
NOPME )( −Σ=
NOP
AME)−Σ
=
NOPRMSE
2)( −Σ=
OOP
RE Σ−Σ
=)(
Mean Error (Bias)
Absolute Mean Error
Root Mean Square Error
Relative Error
Lake Sammamish CH3DModel Error Statistics
Number of Comparisons 4,891 Mean Error (bias) -0.28 oC Absolute Mean Error (AME) 0.80 oC Root Mean Square Error (RMSE)
1.10 oC
Relative Mean Error (%) 6.4
LAKE SAMMAMISH CH3DMean Annual Errors, 1995-2002
-2
-1
0
1
2
1995 1996 1997 1998 1999 2000 2001 2002
Erro
r, o C Bias
AMERMSE
Lake Sammamish CH3DModel Error Statistics
Wind Adjustment Factor
0.60 0.60 0.80 0.85 0.85 0.85 0.85 0.85
Sea-Tac vs. SSAMM RUSSAir Temperature Comparison
All data (outliers removed)
Sea-Tac Air Temp (oC)
0 10 20 30
RU
SS
Air
Tem
p (o C
)
0
10
20
30
ObservationsLinear Regression95% Prediction Intervals1:11:1
y = 0.95(x) + 1.52r2 = 0.9282
Sea-Tac Air Temp (oC)
0 10 20 30
RU
SS
Air
Tem
p (o C
)
0
10
20
30
ObservationsRegression95% Prediction Intervals1:1
y = 0.92(x) + 1.38r2 = 0.9347
Sea-Tac vs. SSAMM RUSSAir Temperature Comparison
7 AM to 6 PM
Sea-Tac Air Temp (oC)
0 10 20 30
RU
SS
Air
Tem
p (o C
)
0
10
20
30
ObservationsRegression95% Prection Intervals1:1
Sea-Tac vs. SSAMM RUSSAir Temperature Comparison
7 PM to 6 AM
y = 1.05(x) + 0.86r2 = 0.9295
Lake Sammamish CH3D Surface Temperatures
Lake Sammamish CH3D Longitudinal Temperatures
CH3D Velocity Animation
Conclusions