Summary number of cells / total cells CASE STUDY 6 Summary...

1
The following methodology was applied to 1) Artificial depressions and flat areas are removed from the DEM using PEM4PIT model with automatic parameter estimation (Grimaldi et al., 2007; Nardi et al., in press; Santini et al., in review); flow directions and contributing areas are characterized using the D8- LTD method (Orlandini et al., 2003) with dampening factor = 1; stream network is extracted using the automated drop analysis combined with the curvature based method (Tarboton et al., 1991; Tarboton and Ames, 2001). Slope is extracted according to maximum downhill criterion. 2) Determination of the Width Function is based on the estimation of hydrologic distances measured along the D8-LTD based steepest slope path for the river network and using the D- method (Tarboton, 1997; Bogaart & Troch, 2006) for the hillslopes. 3) Determination of basin Lag Time from observed data (Bocchiola et al., 2003): Lag time is assumed as the time difference between the net hydrograph and the net rainfall centroids (Chow et al., 1988); net hydrograph was obtained with the fixed base method while net rainfall was obtained with the SCS-CN method using a Curve Number that leads to the equivalency between net rainfall volume and direct runoff volume (USDA, 1986; Chow et al., 1988). 4) Rescaling of WFs are determined weighting the WF with the corresponding flow velocities in the following cases: a) - velocity that varies cell by cell: implementation of Maidment et al. formula (Maidment et al., 1996); V mean was iteratively incremented until the WF-rescaled mean (WFIUH centroid) was equal to previously determined basin Lag Time (Chow et al., 1988); a maximum and minimum limit of respectively 0.01 m/s and 3 m/s is set in order to avoid unrealistic estimation of flow velocities. b) - constant flow velocity for channels (2 m/s) and hillslopes (0.05 m/s) c) - constant flow velocity for channels (1 m/s) and hillslopes (0.05 m/s). d) - constant flow velocity for channels (2 m/s) and hillslopes (0.02 m/s). e) - constant flow velocity for channels (1 m/s) and hillslopes (0.02 m/s). Channel and hillslope velocities of b), c), d), e) were selected according to Botter & Rinaldo (2003). 5) Rainfall-runoff modelling using the WFIUH approach using the rescaled WF in the five approaches of a) to e) and the net rainfall. 6) Comparison results of 5) with actual net hydrographs. 1. Tuscia University, Viterbo, Italy, GEMINI Dep. ([email protected] ; [email protected] ; [email protected]) 2. H2CU, Honors Center of Italian Universities, Sapienza University of Rome , Rome, Italy 3. Tuscia University, Viterbo, Italy, DiSAFRi. ([email protected]) 4. Politecnico di Milano, Dep. of Hydraulics, Roadways, Environmental, and Surveying Engineering. ([email protected]) 1,2 1 3 4 1,2 AGU, Fall Conference 2008 Session H77 GIS Terrain Analysis for Hydrologic Applications Honors Center of Italian Universities www.h2cu.it/ The issue of the a priori estimation of runoff velocities, solved by automatically calibrating the spatially distributed flow velocity field to reproduce the estimated lag time information, provided new insights for the implementation of the WFIUH scheme for the hydrologic prediction in ungauged river basins. Results show a good agreement of simulated against observed hydrographs with particular regard to the shape, the peak and the timing (duration and time to peak) of the hydrologic response. 1) Bocchiola D., De Michele C., Pecora S., Rosso R. (2003), On the response time of Italian watersheds, L'ACQUA, 1, 45-55, In Italian with abstract in English. 2) Bogaart P. W., Troch P. A. (2006), Curvature distribution within hillslopes and catchments and its effect on the hydrological response, Hydrology and Earth System Sciences (10) 6, 925-936. 3) Botter G., and Rinaldo A. (2003), Scale effect on geomorphologic and kinematic dispersion, Water Resour. Res., 39, No 10, 1286, doi: 10.1029/2003WR002154. 4) Chow, V.T., Maidment D.R., Mays L.W. (1988), Applied Hydrology, McGraw-Hill International Editions. 5) Grimaldi S., Nardi F., Di Benedetto F., Istanbulluoglu E., Bras R.L. (2006) A physically-based method for removing pits in digital elevation models. Advances in Water Resources, 30(10) October 2007: 2151-2158 6) Orlandini S., Moretti G., Franchini M., Aldigheri B. and Testa B. (2003), Path-based methods for the determination of non-dispersive drainage directions in grid-based digital elevation models, Water Resources Research 39(6), 1144, DOI: 10.1029/2002WR001639. 7) Maidment D.R., Olivera F., Calver A., Eatherall A., Fraczek W. (1996), Unit Hydrograph derived from a spatially distributed velocity field, Hydrological Processes, Vol 10, 831-844. 8) Nardi F., Grimaldi S., Santini M., Petroselli, Ubertini L. (in press), Hydrogeomorphic properties of simulated drainage patterns using DEMs: the flat area issue, in press on Hydrological Sciences Journal, 2008. 9) Petroselli A., Santini M., Nardi F., Grimaldi S., Vivoni E. (2007), Investigating the spatial variability of hillslope flow velocities, AGU Fall Meeting 2007. 10) Santini M., Grimaldi S., Nardi F., Petroselli A., Rulli M.C. (in review), Pre-Processing algorithms and landslide modelling on remotely sensed DEMs, Geomorphology, in review. 11) Tarboton, D. G., R. L. Bras, and I. Rodriguez-Iturbe (1991), On the extraction of channel networks from digital elevation data, Hydrol. Processes, 5(1), 81- 100. 12) Tarboton D.G. (1997), A new method for the determination of flow directions and upslope areas in grid digital elevation models, Water Resour. Res., 33, 309- 319. 13) Tarboton D.G., and Ames D.P. (2001), Advances in the mapping of flow networks from digital elevation data, in World Water and Environmental Resources Congress, Orlando, Florida, May 20-24, ASCE. 14) USDA-SCS (1986), Urban hydrology for small watersheds. Technical release 55. Washington, DC. The Width Function (WF), the frequency of channel links/contributing area at the same hydrologic distance (i.e. the distance measured along the downhill flow path) to the outlet, is an important hydrogeomorphic property of river basins. The rescaled WF, obtained by weighting the flow distances with the corresponding flow velocity, provides the residency time distribution that is commonly used for representing the geomorphic IUH namely the WF Instantaneous Unit Hydrograph (distribution IUH) or WFIUH for the prediction of the hydrologic response in ungauged basins. The determination of the flow velocities is usually performed lumping the complex dynamics of the heterogenous hydrologic processes of river basins into two main categories: the channelized flow of river channels and the diffusive divergent flow of hillslopes. Nevertheless, the understanding, measuring and preliminary estimation of these variables represents an issue within the WFIUH framework. This work aims to investigate the possibility of implementing the fully spatial distribution of flow velocities throughout the basin, estimated as a function of local terrain properties (e.g. slope, land use etc) and constraining the flow velocity sample to represent the lag time of river basins. Aim is to investigate the impact of considering the heterogeneous properties of hillslope runoff dynamics on the hydrologic response represented with the WFIUH approach with particular regard to the time of concentration, time to peak, total duration, peak discharge and volume distribution (Petroselli et al., 2007). Hydrograph observations are compared to simulation results when using i) constant flow velocities for channel and hillslopes; ii) a spatially variable velocity field calibrated using the lag time information. GEMINI Department - Water Engineering Section DiSAFRi (Dept. of Forest Environment and Resources) Elevations and Blue Line v = cell velocity A = upstream drainage area S = cell steepest slope b, c = coefficients = 0.5 [S b A c ] = watershed average value of slope-area term V mean = average value of the velocity in all cells in the watershed ] [ c b c b mean A A S V v = S Summary Elevations and Blue Line Summary Basin Ayasse - Dora Baltea Outlet Champorcher Code B25 Cellsize (m) 20 Precision integer Area (Km 2 ) 42 PEM4PIT Parameters (β, D, θ ) 0.01, 188, 0.5 Observed Lag Time (hours) 3.60 Summary WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.09 m/s 11.92 2.58 3.60 48.75 42.84 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 9.25 1.66 2.50 54.08 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 10.50 3.16 3.58 49.86 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 21.33 1.75 4.92 36.07 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 22.50 3.75 5.83 34.85 0 0.1 0.2 0.3 0 10 20 30 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 1 hour) Summary Summary WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.19 m/s 7.08 3.58 2.81 327.52 360.61 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 14.33 3.75 4.92 298.63 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 17.83 7.00 7.17 290.19 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 31.33 3.75 9.08 256.35 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 34.00 7.00 11.25 251.42 Basin Mastallone Outlet Ponte Folle Code B15 Cellsize (m) 20 Precision integer Area (Km 2 ) 149 PEM4PIT Parameters (β, D, θ ) 0.01, 160, 0.5 Observed Lag Time (hours) 2.81 CASE STUDY 1 0 0.1 0.2 0.3 0.4 0 10 20 30 40 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 1 hour) Basin Lys Outlet Gressoney St. Jean Code B33 Cellsize (m) 20 Precision integer Area (Km 2 ) 92 PEM4PIT Parameters (β, D, θ ) 0.01, 176, 0.5 Observed Lag Time (hours) 3.96 WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.11 m/s 14.16 3.33 3.96 36.14 37.01 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 17.58 2.66 3.75 35.72 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 19.91 4.50 5.08 35.17 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 40.58 4.00 7.16 31.29 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 42.83 6.75 8.58 30.59 0 0.1 0.2 0.3 0 10 20 30 40 50 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 1 hour) Basin Isorno Outlet Pontetto Code A03 Cellsize (m) 20 Precision integer Area (Km 2 ) 71 PEM4PIT Parameters (β, D, θ ) 0.01, 165, 0.5 Observed Lag Time (hours) 3.3 Elevations and Blue Line 0 0.05 0.1 0.15 0 10 20 30 40 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 0.5 hour) WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.14 m/s 8.33 3.58 3.30 150.80 149.29 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 13.25 3.00 3.83 142.64 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 14.75 5.50 5.75 138.12 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 31.00 3.67 7.00 117.24 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 32.41 6.42 8.75 116.01 Elevations and Blue Line Basin Bisenzio Outlet Gamberame Code A04 Cellsize (m) 20 Precision integer Area (Km 2 ) 150 PEM4PIT Parameters (β, D, θ ) 0.01, 186, 0.5 Observed Lag Time (hours) 7.08 WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.07 m/s 15.83 6.83 7.08 83.92 61.66 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 11.91 3.91 4.25 89.16 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 15.33 7.58 7.00 83.39 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 24.66 3.91 6.50 69.89 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 28.08 7.83 9.16 64.11 0 0.1 0.2 0 10 20 30 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 1 hour) Elevations and Blue Line Basin Chisone Outlet Soucheres Code A06 Cellsize (m) 20 Precision integer Area (Km 2 ) 86 PEM4PIT Parameters (β, D, θ ) 0.01, 182, 0.5 Observed Lag Time (hours) 3.12 Summary WF max WF peak time WF centroid Max Discharge Max Discharge (hours) (hours) (hours) (m 3 /s) Observed Case 'a': (m 3 /s) Maidment et al. Formula: Vmean: 0.15 m/s 7.16 2.66 3.12 71.39 63.44 Case 'b': channel velocity: 2 m/s, hillslope velocity: 0.05 m/s 15.33 2.66 4.58 48.23 Case 'c': channel velocity: 1 m/s, hillslope velocity: 0.05 m/s 16.16 4.66 5.75 45.46 Case 'd': channel velocity: 2 m/s, hillslope velocity: 0.02 m/s 37.00 4.50 9.50 35.02 Case 'e': channel velocity: 1 m/s, hillslope velocity: 0.02 m/s 37.91 5.75 10.66 34.39 0 0.05 0.1 0 10 20 30 40 Time (hours) number of cells / total cells Rescaled WF - case 'a' Rescaled WF - case 'b' Rescaled WF - case 'c' Rescaled WF - case 'd' Rescaled WF - case 'e' Width Function (smoothing window: 0.25 hour) Elevations and Blue Line 0 50 100 150 200 0 40 80 120 Time (hours) Discharge (m 3 /s) 0 10 20 30 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Ranfall Hydrographs comparison (time interval: 0.5 hour) 0 40 80 120 0 40 80 120 Time (hours) Discharge (m 3 /s) 0 10 20 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Rainfall Hydrographs comparison (time interval: 1 hour) 0 20 40 60 70 90 110 130 Time (hours) Discharge (m 3 /s) 0 20 40 60 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Rainfall Hydrographs comparison (time interval: 1 hour) 0 10 20 30 40 70 90 110 130 150 Time (hours) Discharge (m 3 /s) 0 5 10 15 20 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Rainfall Hydrographs comparison (time interval 1 hour) 0 20 40 60 80 50 100 150 200 Time (hours) Discharge (m 3 /s) 0 5 10 15 20 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Rainfall Hydrographs comparison (time interval: 0.25 hour) Dep. of Hydraulics, Roadways, Environmental, and Surveying Engineering 0 100 200 300 400 500 0 50 100 150 Time (hours) Discharge (m 3 /s) 0 20 40 60 Rainfall (mm) Actual Net Discharge Net Discharge case 'a' Net Discharge case 'b' Net Discharge case 'c' Net Discharge case 'd' Net Discharge case 'e' Net Rainfall Hydrographs comparison (time interval: 1 hour) Flow velocity with Maidment et al. (1996) formula Flow velocity with Maidment et al. (1996) formula CASE STUDY 4 CASE STUDY 5 CASE STUDY 2 CASE STUDY 3 CASE STUDY 6 Flow velocity with Maidment et al. (1996) formula Flow velocity with Maidment et al. (1996) formula Flow velocity with Maidment et al. (1996) formula Flow velocity with Maidment et al. (1996) formula

Transcript of Summary number of cells / total cells CASE STUDY 6 Summary...

Page 1: Summary number of cells / total cells CASE STUDY 6 Summary ...dspace.unitus.it/bitstream/2067/1421/1/AGU_2008_WFIUH_final.pdf · ting the fully spatial distribution of flow velocities

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De

Mic

hele

C.,

Peco

ra S

., Ro

sso

R. (2

003)

, On

the

resp

onse

tim

e of

Ital

ian

wat

ersh

eds,

L'A

CQ

UA

, 1, 4

5-55

, In

Italia

n w

ith a

bstr

act i

n En

glis

h.2)

Bog

aart

P. W

., Tr

och

P. A

. (20

06),

Cur

vatu

re d

istr

ibut

ion

with

in h

illsl

opes

and

cat

chm

ents

and

its

effe

ct o

n th

e hy

drol

ogic

al re

spon

se, H

ydro

logy

and

Ear

th S

yste

m S

cien

ces

(10)

6, 9

25-9

36.

3) B

otte

r G.,

and

Rina

ldo

A. (

2003

), Sc

ale

effe

ct o

n ge

omor

phol

ogic

and

kin

emat

ic d

ispe

rsio

n, W

ater

Res

our.

Res.

, 39,

No

10, 1

286,

doi

: 10.

1029

/200

3WR0

0215

4.4)

Cho

w, V

.T.,

Mai

dmen

t D.R

., M

ays

L.W

. (19

88),

App

lied

Hyd

rolo

gy, M

cGra

w-H

ill In

tern

atio

nal E

ditio

ns.

5) G

rim

aldi

S.,

Nar

di F

., D

i Ben

edet

to F

., Is

tanb

ullu

oglu

E.,

Bras

R.L

. (20

06) A

phy

sica

lly-b

ased

met

hod

for r

emov

ing

pits

in d

igita

l ele

vatio

n m

odel

s. A

dvan

ces

in W

ater

Res

ourc

es, 3

0(10

) Oct

ober

200

7: 2

151-

2158

6) O

rlan

dini

S.,

Mor

etti

G.,

Fran

chin

i M.,

Ald

ighe

ri B

. and

Tes

ta B

. (20

03),

Path

-bas

ed m

etho

ds fo

r the

det

erm

inat

ion

of n

on-d

ispe

rsiv

e dr

aina

ge d

irec

tions

in g

rid-

base

d di

gita

l ele

vatio

n m

odel

s, W

ater

Res

ourc

es R

esea

rch

39(6

), 11

44, D

OI:

10.1

029/

2002

WR0

0163

9.7)

Mai

dmen

t D.R

., O

liver

a F.

, Cal

ver A

., Ea

ther

all A

., Fr

acze

k W

. (19

96),

Uni

t Hyd

rogr

aph

deri

ved

from

a sp

atia

lly d

istr

ibut

ed v

eloc

ity fi

eld,

Hyd

rolo

gica

l Pro

cess

es, V

ol 1

0, 8

31-8

44.

8) N

ardi

F.,

Gri

mal

di S

., Sa

ntin

i M.,

Petr

osel

li, U

bert

ini L

. (in

pre

ss),

Hyd

roge

omor

phic

pro

pert

ies

of s

imul

ated

dra

inag

e pa

ttern

s us

ing

DEM

s: th

e fla

t are

a is

sue,

in p

ress

on

Hyd

rolo

gica

l Sci

ence

s Jo

urna

l, 20

08.

9) P

etro

selli

A.,

Sant

ini M

., N

ardi

F.,

Gri

mal

di S

., V

ivon

i E. (

2007

), In

vest

igat

ing

the

spat

ial v

aria

bilit

y of

hill

slop

e flo

w v

eloc

ities

, AG

U F

all M

eetin

g 20

07.

10) S

antin

i M.,

Gri

mal

di S

., N

ardi

F.,

Petr

osel

li A

., Ru

lli M

.C. (

in re

view

), Pr

e-Pr

oces

sing

alg

orith

ms

and

land

slid

e m

odel

ling

on re

mot

ely

sens

ed D

EMs,

Geo

mor

phol

ogy,

in re

view

.11

) Tar

boto

n, D

. G.,

R. L

. Bra

s, a

nd I.

Rod

rigu

ez-It

urbe

(199

1), O

n th

e ex

trac

tion

of c

hann

el n

etw

orks

from

dig

ital e

leva

tion

data

, Hyd

rol.

Proc

esse

s, 5

(1),

81-1

00.

12) T

arbo

ton

D.G

. (19

97),

A n

ew m

etho

d fo

r the

det

erm

inat

ion

of fl

ow d

irec

tions

and

ups

lope

are

as in

gri

d di

gita

l ele

vatio

n m

odel

s, W

ater

Res

our.

Res.

, 33,

309

-319

.13

) Tar

boto

n D

.G.,

and

Am

es D

.P. (

2001

), A

dvan

ces

in th

e m

appi

ng o

f flo

w n

etw

orks

from

dig

ital e

leva

tion

data

, in

Wor

ld W

ater

and

Env

iron

men

tal R

esou

rces

Con

gres

s, O

rlan

do, F

lori

da, M

ay 2

0-24

, ASC

E.14

) USD

A-S

CS

(198

6), U

rban

hyd

rolo

gy fo

r sm

all w

ater

shed

s. T

echn

ical

rele

ase

55. W

ashi

ngto

n, D

C.

The

Wid

th F

unct

ion

(WF)

, the

freq

uenc

y of

cha

nnel

link

s/co

ntri

butin

g ar

ea a

t the

sam

e hy

drol

ogic

dis

tanc

e (i.

e. t

he d

ista

nce

mea

sure

d al

ong

the

dow

nhill

flo

w p

ath)

to

the

outle

t, is

an

impo

rtan

t hy

drog

eom

orph

ic

prop

erty

of

rive

r ba

sins

. The

res

cale

d W

F, o

btai

ned

by w

eigh

ting

the

flow

dis

tanc

es w

ith t

he c

orre

spon

ding

flo

w v

eloc

ity, p

rovi

des

the

resi

denc

y tim

e di

stri

butio

n th

at is

com

mon

ly u

sed

for

repr

esen

ting

the

geom

orph

ic

IUH

nam

ely

the

WF

Inst

anta

neou

s U

nit

Hyd

rogr

aph

(dis

trib

utio

n IU

H)

or W

FIU

H f

or t

he p

redi

ctio

n of

the

hy

drol

ogic

resp

onse

in u

ngau

ged

basi

ns.

The

dete

rmin

atio

n of

the

flo

w v

eloc

ities

is

usua

lly p

erfo

rmed

lum

ping

the

com

plex

dyn

amic

s of

the

he

tero

geno

us h

ydro

logi

c pr

oces

ses

of r

iver

bas

ins

into

tw

o m

ain

cate

gori

es:

the

chan

neliz

ed f

low

of

rive

r ch

anne

ls a

nd t

he d

iffus

ive

dive

rgen

t flo

w o

f hi

llslo

pes.

Nev

erth

eles

s, t

he u

nder

stan

ding

, m

easu

ring

and

pr

elim

inar

y es

timat

ion

of th

ese

vari

able

s re

pres

ents

an

issu

e w

ithin

the

WFI

UH

fram

ewor

k.

This

wor

k ai

ms

to in

vest

igat

e th

e po

ssib

ility

of i

mpl

emen

ting

the

fully

spa

tial d

istr

ibut

ion

of fl

ow v

eloc

ities

th

roug

hout

the

bas

in,

estim

ated

as

a fu

nctio

n of

loc

al t

erra

in p

rope

rtie

s (e

.g.

slop

e, l

and

use

etc)

and

co

nstr

aini

ng th

e flo

w v

eloc

ity s

ampl

e to

repr

esen

t the

lag

time

of ri

ver b

asin

s.

Aim

is to

inve

stig

ate

the

impa

ct o

f con

side

ring

the

hete

roge

neou

s pr

oper

ties

of h

illsl

ope

runo

ff dy

nam

ics

on t

he h

ydro

logi

c re

spon

se r

epre

sent

ed w

ith t

he W

FIU

H a

ppro

ach

with

par

ticul

ar r

egar

d to

the

tim

e of

co

ncen

trat

ion,

tim

e to

pea

k, to

tal d

urat

ion,

pea

k di

scha

rge

and

volu

me

dist

ribu

tion

(Pet

rose

lli e

t al.,

200

7).

Hyd

rogr

aph

obse

rvat

ions

are

com

pare

d to

sim

ulat

ion

resu

lts w

hen

usin

g i)

cons

tant

flo

w v

eloc

ities

for

ch

anne

l and

hill

slop

es; i

i) a

spat

ially

var

iabl

e ve

loci

ty fi

eld

calib

rate

d us

ing

the

lag

time

info

rmat

ion.

GEM

INI D

epar

tmen

t -W

ater

Eng

inee

ring

Sec

tion

DiS

AFR

i (D

ept.

of F

ores

t Env

iron

men

t and

Res

ourc

es)

Elev

atio

ns a

nd B

lue

Line

v =

cell

velo

city

A =

ups

trea

m d

rain

age

area

S =

cell

stee

pest

slo

pe

b, c

= c

oeffi

cien

ts =

0.5

[Sb A

c ] =

wat

ersh

ed a

vera

ge v

alue

of s

lope

-are

a te

rmV

mea

n =

aver

age

valu

e of

the

velo

city

in a

ll ce

lls in

the

wat

ersh

ed

][

cb

cb

mea

n

AA

SV

v⋅

⋅⋅

=S

Sum

mar

y

Elev

atio

ns a

nd B

lue

Line

Sum

mar

y

Basi

nA

yass

e - D

ora

Balte

aO

utle

tC

ham

porc

her

Cod

eB2

5C

ells

ize

(m)

20Pr

ecis

ion

inte

ger

Are

a (K

m2 )

42PE

M4P

IT P

aram

eter

s (β,

D, θ

)0.

01, 1

88, 0

.5O

bser

ved

Lag

Tim

e (h

ours

)3.

60

Sum

mar

yW

F m

axW

F pe

ak ti

me

WF

cent

roid

Max

Dis

char

geM

ax D

isch

arge

(hou

rs)

(hou

rs)

(hou

rs)

(m3 /s

)O

bser

ved

Cas

e 'a

':(m

3 /s)

Mai

dmen

t et a

l. Fo

rmul

a: V

mea

n: 0

.09

m/s

11.9

22.

583.

6048

.75

42.8

4C

ase

'b':

chan

nel v

eloc

ity: 2

m/s

, hill

slop

e ve

loci

ty: 0

.05

m/s

9.25

1.66

2.50

54.0

8C

ase

'c':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.05

m/s

10.5

03.

163.

5849

.86

Cas

e 'd

':ch

anne

l vel

ocity

: 2 m

/s, h

illsl

ope

velo

city

: 0.0

2 m

/s21

.33

1.75

4.92

36.0

7C

ase

'e':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.02

m/s

22.5

03.

755.

8334

.85

0

0.1

0.2

0.3

010

2030

Tim

e (h

ours

)

number of cells / total cells

Res

cale

d W

F - c

ase

'a'

Res

cale

d W

F - c

ase

'b'

Res

cale

d W

F - c

ase

'c'R

esca

led

WF

- cas

e 'd

'R

esca

led

WF

- cas

e 'e

'

Wid

th F

unct

ion

(sm

ooth

ing

win

dow

: 1 h

our)

Sum

mar

y

Sum

mar

yW

F m

axW

F pe

ak ti

me

WF

cent

roid

Max

Dis

char

geM

ax D

isch

arge

(hou

rs)

(hou

rs)

(hou

rs)

(m3 /s

)O

bser

ved

Cas

e 'a

':(m

3 /s)

Mai

dmen

t et a

l. Fo

rmul

a: V

mea

n: 0

.19

m/s

7.08

3.58

2.81

327.

5236

0.61

Cas

e 'b

':ch

anne

l vel

ocity

: 2 m

/s, h

illsl

ope

velo

city

: 0.0

5 m

/s14

.33

3.75

4.92

298.

63C

ase

'c':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.05

m/s

17.8

37.

007.

1729

0.19

Cas

e 'd

':ch

anne

l vel

ocity

: 2 m

/s, h

illsl

ope

velo

city

: 0.0

2 m

/s31

.33

3.75

9.08

256.

35C

ase

'e':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.02

m/s

34.0

07.

0011

.25

251.

42

Basi

nM

asta

llone

Out

let

Pont

e Fo

lleC

ode

B15

Cel

lsiz

e (m

)20

Prec

isio

nin

tege

rA

rea

(Km

2 )14

9PE

M4P

IT P

aram

eter

s (β

, D, θ

)0.

01, 1

60, 0

.5O

bser

ved

Lag

Tim

e (h

ours

)2.

81

CA

SE

STU

DY

1

0

0.1

0.2

0.3

0.4

010

2030

40T

ime

(hou

rs)

number of cells / total cells

Res

cale

d W

F - c

ase

'a'

Res

cale

d W

F - c

ase

'b'

Res

cale

d W

F - c

ase

'c'R

esca

led

WF

- cas

e 'd

'R

esca

led

WF

- cas

e 'e

'

Wid

th F

unct

ion

(sm

ooth

ing

win

dow

: 1 h

our)

Basi

nLy

sO

utle

tG

ress

oney

St.

Jean

Cod

eB3

3C

ells

ize

(m)

20Pr

ecis

ion

inte

ger

Are

a (K

m2 )

92PE

M4P

IT P

aram

eter

s (β

, D, θ

)0.

01, 1

76, 0

.5O

bser

ved

Lag

Tim

e (h

ours

)3.

96

WF

max

WF

peak

tim

eW

F ce

ntro

idM

ax D

isch

arge

Max

Dis

char

ge(h

ours

)(h

ours

)(h

ours

)(m

3 /s)

Obs

erve

dC

ase

'a':

(m3 /s

)M

aidm

ent e

t al.

Form

ula:

Vm

ean:

0.1

1 m

/s14

.16

3.33

3.96

36.1

437

.01

Cas

e 'b

':ch

anne

l vel

ocity

: 2 m

/s, h

illsl

ope

velo

city

: 0.0

5 m

/s17

.58

2.66

3.75

35.7

2C

ase

'c':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.05

m/s

19.9

14.

505.

0835

.17

Cas

e 'd

':ch

anne

l vel

ocity

: 2 m

/s, h

illsl

ope

velo

city

: 0.0

2 m

/s40

.58

4.00

7.16

31.2

9C

ase

'e':

chan

nel v

eloc

ity: 1

m/s

, hill

slop

e ve

loci

ty: 0

.02

m/s

42.8

36.

758.

5830

.59

0

0.1

0.2

0.3

010

2030

4050

Tim

e (h

ours

)

number of cells / total cells

Res

cale

d W

F - c

ase

'a'

Res

cale

d W

F - c

ase

'b'

Res

cale

d W

F - c

ase

'c'R

esca

led

WF

- cas

e 'd

'R

esca

led

WF

- cas

e 'e

'

Wid

th F

unct

ion

(sm

ooth

ing

win

dow

: 1 h

our)

Basi

nIs

orno

Out

let

Pont

etto

Cod

eA

03C

ells

ize

(m)

20Pr

ecis

ion

inte

ger

Are

a (K

m2 )

71PE

M4P

IT P

aram

eter

s (β

, D, θ

)0.

01, 1

65, 0

.5O

bser

ved

Lag

Tim

e (h

ours

)3.

3

Elev

atio

ns a

nd B

lue

Line

0

0.050.1

0.15

010

2030

40T

ime

(hou

rs)

number of cells / total cells

Res

cale

d W

F - c

ase

'a'

Res

cale

d W

F - c

ase

'b'

Res

cale

d W

F - c

ase

'c'R

esca

led

WF

- cas

e 'd

'R

esca

led

WF

- cas

e 'e

'

Wid

th F

unct

ion

(sm

ooth

ing

win

dow

: 0.5

hou

r)

WF

max

WF

peak

tim

eW

F ce

ntro

idM

ax D

isch

arge

Max

Dis

char

ge(h

ours

)(h

ours

)(h

ours

)(m

3 /s)

Obs

erve

dC

ase

'a':

(m3 /s

)M

aidm

ent e

t al.

Form

ula:

Vm

ean:

0.1

4 m

/s8.

333.

583.

3015

0.80

149.

29C

ase

'b':

chan

nel v

eloc

ity: 2

m/s

, hill

slop

e ve

loci

ty: 0

.05

m/s

13.2

53.

003.

8314

2.64

Cas

e 'c'

:ch

anne

l vel

ocity

: 1 m

/s, h

illsl

ope

velo

city

: 0.0

5 m

/s14

.75

5.50

5.75

138.

12C

ase

'd':

chan

nel v

eloc

ity: 2

m/s

, hill

slop

e ve

loci

ty: 0

.02

m/s

31.0

03.

677.

0011

7.24

Cas

e 'e

':ch

anne

l vel

ocity

: 1 m

/s, h

illsl

ope

velo

city

: 0.0

2 m

/s32

.41

6.42

8.75

116.

01

Elev

atio

ns a

nd B

lue

Line

Basi

nBi

senz

ioO

utle

tG

ambe

ram

eC

ode

A04

Cel

lsiz

e (m

)20

Prec

isio

nin

tege

rA

rea

(Km

2 )15

0PE

M4P

IT P

aram

eter

s (β

, D, θ

)0.

01, 1

86, 0

.5O

bser

ved

Lag

Tim

e (h

ours

)7.

08

WF

max

WF

peak

tim

eW

F ce

ntro

idM

ax D

isch

arge

Max

Dis

char

ge(h

ours

)(h

ours

)(h

ours

)(m

3 /s)

Obs

erve

dC

ase

'a':

(m3 /s

)M

aidm

ent e

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