time-varying analysis of parameter sensitivity at multiple ... · time-varying analysis of...

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Time-varying analysis of parameter sensitivity at

multiple evaluation scales for hydrologic and

sediment modeling

Presented by: Hui Xie

Authors: Hui Xie, Zhenyao Shen*, Lei Chen, Guoyuan Wei

Beijing Normal University

July 2016

Outline

2

3

BackgroundIntroduction

1

Methodology

Results and discussion

Objectives

Watershed descriptionModel setup

Hydrology sectionSediment section

FAST+Moving windows

3 Summary

Background

Supports model calibration

Background

1

Multiple evaluation scales2

Which period are helpful for identification?

Under which condition a specific process matters?

Time-varying analysis

Different processes act over different time scales

Maximize information content

Guide measurement campaigns

No previous research concerned

Background

3

Objective4

Support management plan

Time-varying + multiple evaluation scales for

SEDIMENT modeling

Improve the understanding of hydrologic and sediment

processes

Methodology

Study site

Methodology

1

Zhangjiachong

watershed

Located at the head of

TGRA, 1.6km2

Model setup2 HSPF

Methodology

IMPERLND

PERLND

RCHRES

Watershed

Hydrology Section

Flows & Storages

Model setup

Model setup

Flows & Storages

Hydrology Section

Detachment & Washoff

Sediment Section

Scour & Deposition

Parameter Description Unit Possiblerange

LZSN Low zone nominal soil moisture storage in. 2.0-15.0

INFILT Index to mean soil infiltration rate in./h 0.001-0.50

KVARY Parameter to describe non-linear groundwaterrecession rate in-1 0.0-5.0

AGWRC Groundwater recession rate day-1 0.85-0.999

DEEPFR Fraction of infiltrating water which enters deepaquifers none 0.0-0.50

BASETP Fraction of potential evapotranspiration whichfulfilled only as outflow exists. none 0.0-0.20

AGWETP Fraction of remaining evapotranspiration thatbe met from active groundwater storage. none 0.0-0.20

CEPSC Interception storage capacity. in. 0.01-0.40

UZSN Nominal upper zone soil moisture storage. in. 0.05-2.0

INTFW Interflow inflow parameter. none 1.0-10.0

IRC Interflow recession parameter. day-1 0.3-0.85

LZETP Index to lower zone evapotranspiration. none 0.1-0.9

Hydrologic parameters1

Parameter Description Unit Possiblerange

SMPF Management Practice (P) factor from USLE none 0.0-1.0

KRER Coefficient in the soil detachment equation in./h 0.05-0.75

JRER Exponent in the soil detachment equation in-1 1.0-3.0

AFFIX Daily reduction in detached sediment day-1 0.01-0.50

COVER Fraction land surface protected from rainfall none 0.0-0.98

KSER Coefficient in the sediment washoff equation none 0.1-10.0

JSER Exponent in the sediment washoff equation none 1.0-3.0

TAUCD1 Critical bed shear stress for deposition in. 0.001-1.0

TAUCS1 Critical bed shear stress for scour in. 0.05-2.0

TAUCD2 Critical bed shear stress for deposition of silt none 1.0-10.0

TAUCS2 Critical bed shear stress for scour of day-1 0.3-0.85

Sediment parameters2

Sensitivity analysis

Methodology

3

… • Global method

…

• Variance decomposition

… • Non-linear models

… • Computationally

efficient

Fourier Amplitude Sensitivity Test (FAST)

Saltelli et al. (1999)

Sensitivity analysis

Methodology

3

Fourier Amplitude Sensitivity Test (FAST)

… • Global method

…

• Variance decomposition

… • Non-linear models

… • Computationally

efficient

50,000 samplings for hydrologic

parameters

20,000 samplings for sediment

parameters

Parameters uniformly distributed

Multiple moving windows

Methodology

4

… •Objective function

… •Moving window sizes

2, 4, 8, 30, 60, 180, 360, 540, 720 days

(Massmann et al., 2014)

Results and Discussion

17

Results and discussion

1

NSE=0.82

R2=0.83NSE=0.59

R2=0.61

Model calibration for daily streamflow and sediment

y = 0.6199x + 78.279

R² = 0.60737

0

500

1000

1500

2000

2500

0 500 1000 1500 2000 2500 3000

18

Results and discussion

2 Time-varying sensitivity of HYDROLOGIC parameters

Parameter

groups

1

2

3

4

AGWRC, KVARY

Base flow

INTFW, IRC

Interflow

Moisture

redistribution

LZSN, UZSN, INFILT

ET, water loss

LZETP, BASETP,

DEEPFR, CEPSC

19

1 Base flow

1 Base flow

High sensitivities in the full period

Especially high in dry periods

More than 180 days for identification

Base flow is critical

Should be calibrated

Long length of observation

2 Interflow

2 Interflow

Highest sensitivities in wet period

Monitoring plan arrangedaccording to the sensitive areasStrong correlation with precipitation

2 – 720 days for identification

3 Moisture redistribution

3 Moisture redistribution

LZS more steady

UZS active in the first year

Moisture distribution3

Moisture distribution

Active in the first year when water fill up the lower storages Percolation & Infiltration more important than water

movement into IFS

3

4 ET

4 ET

4 ET

ET from LZS is critical Long length of monitoring required Impact on wet periods

30

Results and discussion

2 Time-varying sensitivity of SEDIMENT parameters

Parameter

groups

1

2

3

4

KRER, JRER

Detachment

KSER, JSER

Washoff

Scour/deposition

TAUCD, TAUCS

Controllable

SMPF, COVER

Detachment1T

SS

(mg

/L)

Detachment1

Erodibility of the Soil Type

Strong correlation with Precipitation

2 WashoffT

SS

(mg

/L)

2 Washoff

Effects of surface condition and flow Sensitive in most of the time 45 days or more required for identification Management practices’ impact on KSER

2 Scour/depositionTA

U

3 Scour/depositionTA

U

3 Scour/deposition

Determine the Sediment dynamics in reach Sensitivity and evaluation scales Varies as Bed

Shear Stress changes Practices in the channels make sense

TA

U

4 ControllableT

SS

(mg

/L)

4 Controllable

Similar to P and C factors in USLE High sensitivity during the wet season

Management practices are effective when evaluatedin scales of more than 60 days

Summary

Summary

At what time period specific parameters are sensitive is defined.

Over what length of measurement to maximize the sensitivity

signals is defined.

The results help support measurement campaigns, calibration,

and management plan.

THANK YOUAny question and suggestion?

Contact: bnuxiehui@hotmail.com