The 11th AIM International Workshop

Land surface dependent Water balance
modeling of Korea

19-Feb-2006
H.C. Jung, Y. Matsuoka(Kyoto University, Japan)

Objectives
1. The effects of land use and land cover on theclimate will accelerate warming by deforestationand change the future impacts on the water balanceand ecosystems by a complicated interplay of land
surface energy balance including soil moisture,
rainfall, snow, albedo etc.
2. To define, describe and quantify the relative andabsolute importance of potential climate change tothe hydrology, water resources and ecosystem, land
surface database were parameterized and land
surface dependent potential evapotranspiration
models were developed

Contents of presentation• The core of the research consists of development of
1. Land surface database- Land use and cover data
- Leaf Area Index- Soil pedon data and Water holding capacity

2. Hydro database- Basin and river network delineation with GIS- Water level DB gathering and converting todischarge

3. Surface dependent PET model test
- Shuttleworth and wallace(SW) model- Penman Monteith(PM) model- FAO 24 style PM modelConceptual diagram of hydrologic impact
assessment with land surface heterogeneity(Grid-based )Regional Climate(% area/ LAI, SAI )Potential ET(Penman-Monteith)

Land SurfaceInformation(Veg. Root Depth )Snow Accumulation &Melting
Soil Water Storage(Soil drying function)

Soil Information(FC,AWC, 5km)

Actual ET/
Excess Water (Xs)

Watershed Boundary

Runoff(Tank model)River Routing(Cascade reservoirs)

FAO Soil Data
(DPRK)
1:25,000 Soil Map(ROK)
Saxton PTF

Discharge
DB(Optimization )RiverRiver Discharge
Discharge(5daymean,(5day mean, Supply)Supply)Water Balance and Hydrologic model
Grid-based
ATMOSPHERE
Precipitation, Pt

Sublimation

Ps

PrET

SNOW
PACK

ROOT
ZONESWE

SnowMt

SW

FC

Xr

Water
Rs
Soil Moisture,SM

Upper basin
q1

Sc
S1

Tank1
b1

a1

q2

f1

S2

Tank2

a2

q3

S3

SurfaceTank

a3

Construction of Land surface database : Land
Cover and Land Use
Global and Local database of LC :1. 30 m Landsat LC, 7classes, K.pen. (area)
2. 5m LU, 23 classes, ROK (attribute)
3. IGBP 1km LC (attribute, DPRK)LC Percentage and Primary Type(1,2,3)

Construction of Land surface database : Leaf
Area Index
Monthly LAI data from MODIS satellite images :1. 6 year (2000~2006), 4 km, + LC % Data
2. mean monthly LAI for LC types by latitude
LC TYPE

JAN

FEB

MAR

APR

MAY

JUN

JUL

AUG

SEP

OCTNOVDEC

Coniferous Forest (30-40N)

1.3

1.4

1.3

2.2

4.0

4.9

5.0

4.6

3.9

3.2

1.7

1.4

Coniferous Forest (40-50N)

1.3

1.3

1.2

1.4

2.4

4.9

5.0

4.2

3.4

1.6

1.2

1.2

Deciduous Forest (30-40N)

0.7

0.7

0.6

1.43.86.0

5.6

5.3

4.6

3.0

1.1

0.8

Deciduous Forest (40-50N)

0.8

0.8

0.6

0.9

1.9

5.0

5.2

4.4

3.8

1.5

0.9

0.8

Agriculture

0.2

0.2

0.3

0.3

0.4

0.9

1.9

2.4

2.0

0.7

0.3

0.2

Mt. JUMBONGSAN RES. (Deciduous forest)

SUWON (Rice paddy)
77

LAI seasonality by land cover type

66

75

Coniferous Forest (30-40N)
Coniferous Forest (40-50N)
Deciduous Forest (30-40N)
Deciduous Forest (40-50N)
Agriculture
GrassLAI

463254LAI53210100200300

Day of year (DOY), year 2000-2005

KWANGNUNG (Coniferous forest)
740LAI010100200300

Day of year (DOY), year 2000-2005

Mt. HALLASAN PARK (Coniferous forest)

376625544LAILAI

133022110234567Month
0100200300

Day of year (DOY), year 2000-2005

89101112100100200300

Day of year (DOY), year 2000-2005

Seasonality of LAI by land cover type and location

Construction of Land surface database : Soilpedology and Water holding capacityθf = 42.5080 -0.3510Psand -0.1030 Psilt + 1.9231Pom(n=1006, r2=0.717)

θw = 1.5515 +0.0754Psilt +0.2732 Pclay + 1.3544Pom(n=1006, r2=0.664)50300

Proposed

R2 = 0.7463

Difference of available water contents (100 cm 3 / cm-3)
between PTF models and mesured AWC

Available water contents estimated by linear
regression model (mm/m)

Linear regressions for prediction of soil water contents at FC and WP by thestepwise multi-linear linear regression

250

200

150

10050

SaxtonBatjes25Rawls

0-250050

100150200

Measured available water contents (mm/m)

250-500204060
Silt (%)

Comparison of available water contents estimated by proposed PTF model results.

80100

Total available water capacity and field capacity ofthe soil in Korea for 100㎝ depth

nTAWC = ∑ [ AWC j ⋅ t j ⋅(1 − s j )]j =1

Construction of Hydro database : Basin
delineation of Korean peninsula
GIS based Hydro-Network and Basin DB :1. SRTM 3sec DEM
2. 1:25,000 rivernet for stream burning
3. National basin map of ROK
4. 177 stream monitoring station for area
comparison
140100000

R 2 = 0.9994

n=174120100
F re g u e n c y

100080604020100> 50

5~ 10-5 ~ 5E rror Range(% )30~ 5010000020~ 3010000

10~ 201000

R eported Area (km 2)-1 0 ~ -5100-2 0 ~ -1 0

10-3 0 ~ -2 0

Ba s in a r e a c o mp a r is o n ( L o g -lo g p lo t)
10-5 0 ~ -3 00< -5 0Calculated Area (km2)

10000Construction of Hydro database : Discharge DB andWatershed delineation
GIS based Hydro-Network and Basin
DB :1. ROK- 60 station, daily water level
2. DPRK- GRDC monthly 7station
3. more than 5 year records foroptimzation

Catchments

Watershed

HydroNet

Comparison of land surface dependent PET
between PM and SW Model (10yr mean)
zPenman-Monteith (PM)PETSW

ΔRn + c p ρDa / ra4

Δ + γ + γ (rc / ra )3.5

zShuttleworth and Wallace (SW)m o n th ly m e a n P E T (m m /d a y)

ct Lv ρ w E ps =4.5

-Dividing Transpiration and Evaporation- More accurate and theoretical approach

ct Lv ρ w E ps = Cc M c + C g M g
Mc =Mg =

32.5
2
1.5
1

ΔRn + (c p ρDa − Δrac R g ) /( raa + rac )0.5

Δ + γ + γrsc /(raa + rac )0

ΔRn + [c p ρDa − Δrag ( Rn − Rg )] /(raa + rag )Δ + γ + γrsg /(raa + rag )

PETPM

123

45

67Month89101112

Ratio of Transpiration and Evaporation at
deciduous forest-dominant basin by SW model
4.5
4m onthly m ena PE T (m m /day)

TREV

3.5
3
2.5
2
1.5
1
0.5
01234567M onth89101112PET by land cover type using SW model
12conSW
decSW

10PE T SW (mm/day)agSW

86420131 61 91 121 151 181 211 241 271 301 331 361
D OYConiferous
12conSWconPM

P E T (m m /d a y )10Agriculture Forest

8664agPM

50Deciduous
1 29 57 85 113
141 169 Forest
197 225 253 281 309 337 365
DOY
decSW

decPM

P E T (m m /d a y )212agSW

43210P E T (m m /d a y )18061 28 55 82 109 136 163 190 217 244 271 298 325 352

4DOY

201 29 57 85 113 141 169 197 225 253 281 309 337

Thanks !