A Satellite Perspective on Joumlkulhlaup in Greenland
location of potential joumlkulhlaup lakes and
calculation of water discharges using remote sensing techniques
13-02-2012 INUTEK Nytaringrskur 2012
Morten LarsenMSc Water and Environment
Asiaq ndash Greenland Survey
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
What is a joumlkulhlaup
A joumlkulhlaup is a very intense flood where a water reservoir releases a large amount of water abruptly
The water reservoir is filled by water over time and when the level reaches a critical point the reservoir is emptied
GeoBasis August 11th 2009 GeoBasis August 12th 2009
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
The aim of the work bull To develop a remote sensing method for locating potential
joumlkulhlaup lakesbull To develop a remote sensing method for assessing the water
volume during a joumlkulhlaup bull To build up knowledge about remote sensing in Greenland
Why developing the methods1 Joumlkulhlaups influences the ecosystem2 Joumlkulhlaups are a risk for human activity in downstream areas3 Joumlkulhlaups affects the design and construction of hydro power
plants4 Joumlkulhlaup frequency and magnitude can be used in climate
change research
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
What is a joumlkulhlaup
A joumlkulhlaup is a very intense flood where a water reservoir releases a large amount of water abruptly
The water reservoir is filled by water over time and when the level reaches a critical point the reservoir is emptied
GeoBasis August 11th 2009 GeoBasis August 12th 2009
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
The aim of the work bull To develop a remote sensing method for locating potential
joumlkulhlaup lakesbull To develop a remote sensing method for assessing the water
volume during a joumlkulhlaup bull To build up knowledge about remote sensing in Greenland
Why developing the methods1 Joumlkulhlaups influences the ecosystem2 Joumlkulhlaups are a risk for human activity in downstream areas3 Joumlkulhlaups affects the design and construction of hydro power
plants4 Joumlkulhlaup frequency and magnitude can be used in climate
change research
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
What is a joumlkulhlaup
A joumlkulhlaup is a very intense flood where a water reservoir releases a large amount of water abruptly
The water reservoir is filled by water over time and when the level reaches a critical point the reservoir is emptied
GeoBasis August 11th 2009 GeoBasis August 12th 2009
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
The aim of the work bull To develop a remote sensing method for locating potential
joumlkulhlaup lakesbull To develop a remote sensing method for assessing the water
volume during a joumlkulhlaup bull To build up knowledge about remote sensing in Greenland
Why developing the methods1 Joumlkulhlaups influences the ecosystem2 Joumlkulhlaups are a risk for human activity in downstream areas3 Joumlkulhlaups affects the design and construction of hydro power
plants4 Joumlkulhlaup frequency and magnitude can be used in climate
change research
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
1 Introduction
13-02-2012 INUTEK Nytaringrskur 2012
The aim of the work bull To develop a remote sensing method for locating potential
joumlkulhlaup lakesbull To develop a remote sensing method for assessing the water
volume during a joumlkulhlaup bull To build up knowledge about remote sensing in Greenland
Why developing the methods1 Joumlkulhlaups influences the ecosystem2 Joumlkulhlaups are a risk for human activity in downstream areas3 Joumlkulhlaups affects the design and construction of hydro power
plants4 Joumlkulhlaup frequency and magnitude can be used in climate
change research
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
2 Study area
13-02-2012
Study area 16000 km2
Lake North
Lake SouthHydrological station
INUTEK Nytaringrskur 2012
Maps by KMS
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Mapping lakes
Mapping glaciers
Mapping surface
anomalies
Spatial location analysis
Potential joumlkulhlaup lakes
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
1st task - Mapping lakes
bull Tasseled cap transformationbull Surface classified as water if the brightness
index gt 04 and the wetness index gt 0
bullMulti-year observation Time series of LANDSAT scenes from late summers 2003-2009bull If surface is classified as water in at least 5 out
of 6 years it is mapped as water
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
2nd task - Mapping glaciers
bull New image produced as average of the Tasseled cap parameters in the LANDSAT time series
bull Unsupervised classification with 50 spectral classes
bull Spectral classes thematically coded into glacier ice or non-glacier ice
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
The NDVI anomaly is the difference between NDVI for a given year and mean NDVI for all years in the LANDSAT time series
3rd task - Mapping surface anomalies
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Area selection threshold
Number of potential joumlkulhlaups
No restriction 336
50000 m2 73
250000 m2 20
1000000 m2 5
4th task ndash Spatial location analysis
Glacier ice
Surface anomaly
Lake
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
3 Location of potential joumlkulhlaups
13-02-2012
Results Discussion
bull All in all the method showed good resultsbull Ice covered lakes were difficult to
classify Two known joumlkulhlaups were not selected due to this problembull Further development in
discriminating between glacier and lake ice is neededbull Only joumlkulhlaup with great changes
in the surface area are mapped
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
water volume (before joumlkulhlaup)
- water volume (after joumlkulhlaup)
= water volume (joumlkulhlaup)
4 Water volume assessmentDeveloping a method only based on satellite images
Water volume difference The method
bull Extract a DEM from ASTER stereo images at lowest possible water levelbull Find a relation between the surface
area and the volume in the lakebull Estimate water surface areas from a
LANDSAT time seriesbull Calculate water volumes in the lake
from the relation
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment
100E+07 150E+07 200E+07 250E+07 300E+07 350E+07000E+00
200E+08
400E+08
600E+08
800E+08
100E+09
120E+09
140E+09
160E+09
180E+09
Area [m2]
Volu
me
[m3]
DEM extracted for Lake North August 8th 2004
Relation between the water surface area and the volume
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessmentThe water surface area time series
1998
07
24
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
000E+00
500E+06
100E+07
150E+07
200E+07
250E+07
300E+07
350E+07
Area
[m2]
LANDSAT scenes from 1999-2010
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
4 Water volume assessment19
980
724
1999
12
06
2001
04
19
2002
09
01
2004
01
14
2005
05
28
2006
10
10
2008
02
22
2009
07
06
2010
11
18
2012
04
01
-50E+08
00E+00
50E+08
10E+09
15E+09
20E+09
Lake
vol
ume
[m3]
Water volumes
200
0
300
0
400
0
500
0
600
0
700
0
800
0
900
0
100
00
110
00
120
00-60E+08
-40E+08
-20E+08
00E+00
20E+08
40E+08
60E+08
80E+08
10E+09
12E+09
14E+09
Rsup2 = 099580910315133
Rsup2 = 0
Accumulated positive degree days
198 km3
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
Table of contents
13-02-2012
1 Introduction2 Study area3 Location of potential joumlkulhlaups lakes4 Water volume assessment5 Verification
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
5 Verification
13-02-2012
Lake North
Lake South
Hydrological station
Lake North
Lake South Lake South
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
ISTA water balance equation
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
where Qjoumlkulhlaup is inflow from joumlkulhlaup [m3s]Qinflow is inflow from other sources [m3s]QISTA is discharge out of Lake ISTA [m3s]t is time [s]VOLISTA is volume of water stored
in Lake ISTA [m3]
5 Verification
Qjoumlkulhlaup
QISTA
Qinflow
Qinflow
VOLISTA
Qinflow
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
Estimating Qinflow
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
Qinflow is mainly from the glacier
5 Verification
Qinflow
Qinflow
Qinflow
0 50 100 150 200 250 30000E+00
50E+07
10E+08
15E+08
20E+08
25E+08
30E+08
35E+08
Rsup2 = 0945598179463255
Positive degree days per month
Inflo
w to
Lak
e IS
TA p
er m
onth
[m
3]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
Estimating the water volume
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
VOLISTA
00E+00 20E+08 40E+08 60E+08 80E+08 10E+0995
100
105
110
115
120
Volume in Lake ISTA [m3]
Wat
er le
vel [
m]
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
Estimating QISTA
Qjoumlkulhlaup dt + Qinflow dt = QISTA dt + dVOLISTA
5 Verification
QISTA
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
5 VerificationResults
Lake North Lake South Lake South
September 2002
August 2003
September 2007
Water balance
QISTAmiddotdt [m3] 125109 006109 005109
VOLISTA[m3] 064109 024109 015109
Qinflow middotdt [m3] 003109 002109 002109
Qjoumlkulhlaupmiddotdt [m3] 185109 028109 018109
RS Vjoumlkulhlaup[m3] 198109 028109 019109
Difference 7 04 2
Discussion
The method showed reliable results for the two test lakes
Challenge to obtain ASTER stereo images immediately after a joumlkulhlaup
Challenge to derived reliable surface areas from LANDSAT due to ice shadows and clouds
The method is less accurate for lakes with a steep bathymetry
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
13-02-2012
The project was funded by The Commission for Scientific Research in Greenland
The project was carried out by Eva Maumltzler AsiaqBo Naamansen AsiaqMorten Larsen AsiaqChristian Toslashttrup GRASDorthe Petersen AsiaqKisser Thorsoslashe Asiaq
INUTEK Nytaringrskur 2012
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