1/22/2010
Rest of the team
Satellite Imagery and the
Geospatial Revolution in
Geography – measuring
changes in the water
quality of Waikato’s
lakes over the last
decade.
Mat Allan
Brendan Hicks
Glen Stichbury
Lars Brabyn, Glen Stichbury, Mat Allan, and Brendan Hicks
University of Waikato
Waikato Lakes
Landsat 7 Scenes
Tongariro National Park
Lake Waikeremoana
Satellite
Launch Date
Landsat 1
23 July 1972
Landsat 2
22 January 1975
Landsat 3
5 March 1978
Landsat 4
16 July 1982
Landsat 5
Landsat 6
1 March 1984
October 1993
Landsat 7
15 April 1999
Notes
Decommissioned
1978
Decommissioned
1982
Decommissioned
1983
Decommissioned
2001
Operational
Failed on launch
Operating in SLC-Off
mode after May 2003
1
1/22/2010
Electromagnetic Energy
In 2009 NASA allowed public access to its Landsat
Archive
Images (800MB) can be downloaded through the
internet
88 downloaded for the Waikato region - 65 Landsat 7
and 28 Landsat 5 images
62 for Taupo/Rotorua
• All matter at
temperature above
absolute zero (0°K or 273°C continuously
emits EM radiations.
• We only see a small part
of the EM radiation
(visual frequencies),
however instruments
can detect the other
frequencies.
Band 1 (Blue)
Near infra-red band
displayed using red
Blue
Band 2 (Green)
Green
Band 3 (Red)
True Colour Composite
Thermal infra-red band
displayed using red
Red
Landsat 7 Radiometric Characteristics of the ETM+ Sensor
Band Number
Spectral Range (in Microns)
EM Region
Generalised Application Details
1
0.45 - 0.52
Visible Blue
Coastal water mapping, differentiation of vegetation from soils
2
0.52 - 0.60
Visible Green
Assessment of vegetation vigour
3
0.63 - 0.69
Visible Red
Chlorophyll absorption for vegetation differentiation
4
0.76 - 0.90
Near Infrared
Biomass surveys and delineation of water bodies
5
1.55 - 1.75
Middle Infrared
Vegetation and soil moisture measurements; differentiation
between snow and cloud
6
10.40- 12.50
Thermal Infrared
Thermal mapping, soil moisture studies and plant heat stress
measurement
7
2.08 - 2.35
Middle Infrared
Hydrothermal mapping
8
0.52 - 0.90 (panchromatic)
Green, Visible Red, Near Infrared
Large area mapping, urban change studies
Regional Councils manually monitor water quality of
some lakes using field samples.
Our research investigates whether some of this
monitoring can be measured using remote sensing.
The measurements that we are researching include:
•Water clarity using Secchi depth – a disk is lowered into
the water until it can not be seen.
•The total suspended solids
•Chl a
•Temperature
2
1/22/2010
Green dots are sample locations
Sample Location Lake
317-4
317-2
315-3
303-4
326-4
324-2
324-11
317-4
317-2
315-3
303-4
326-4
324-2
324-11
330-14
326-7
326-4
324-2
292-6
317-4
301-8
1456-3
330-14
326-4
324-2
292-6
317-4
301-8
317-4
301-8
1456-3
330-14
326-7
Lake Rotomanuka
Lake Rotomanuka
Lake Rotokauri
Lake Ngaroto
Lake Waikare
Lake Waahi
Lake Waahi
Lake Rotomanuka
Lake Rotomanuka
Lake Rotokauri
Lake Ngaroto
Lake Waikare
Lake Waahi
Lake Waahi
Lake Whangape
Lake Waikare
Lake Waikare
Lake Waahi
Lake Hakanoa
Lake Rotomanuka
Lake Maratoto
Lake Serpentine
Lake Whangape
Lake Waikare
Lake Waahi
Lake Hakanoa
Lake Rotomanuka
Lake Maratoto
Lake Rotomanuka
Lake Maratoto
Lake Serpentine
Lake Whangape
Lake Waikare
Image Date B1 Reflectance B3 Reflectance Secchi Disk Depth Total Suspended Solids Turbidity
Measurement
Measurement
Measurement
20000330
0.04221026
0.03317539
1.33
2
2.93
20000330
0.04930923
0.04374811
0.25
33
24.6
20000330
0.06073115
0.05490274
0.25
30
54.3
20000330
0.05183095
0.05021353
0.27
21
20
20000330
0.2132807
0.3099674
0.06
309
362
20000330
0.07087738
0.06897037
0.42
13
9.7
20000330
0.06197718
0.05746049
0.51
11
7.73
20010317
0.03480162
0.02659595
1.32
4
3.89
20010317
0.03744591
0.03241909
0.68
20
10.8
20010317
0.04783706
0.04265033
0.96
22
18.3
20010317
0.04385421
0.04570748
0.67
23
15.4
20010317
0.2118998
0.3016519
0.05
396
338
20010317
0.06147066
0.05280007
0.76
12
10.6
20010317
0.05519001
0.04717491
0.82
11
9.32
20060227
0.0811879
0.08587245
0.05
141
155
20060227
0.09483861
0.1188693
0.15
119
94
20060227
0.08616339
0.1073612
0.15
111
80.9
20060227
0.1115512
0.1346549
0.09
66
65.4
20060227
0.06268925
0.06081926
0.39
23
24.3
20070926
0.03006514
0.02588525
1.51
5
3.79
20070926
0.02710908
0.01979015
1.49
3
2.12
20070926
0.02845661
0.01972971
3.04
3
1.25
20080827
0.1014989
0.1265719
0.69
9.9
12
20080827
0.1112034
0.1437257
0.19
69
76
20080827
0.09549143
0.08912871
1.11
5.7
9.1
20080827
0.0770068
0.0775084
0.88
9.9
12
20080827
0.03943239
0.02888409
0.89
4.2
2.7
20080827
0.03385925
0.0220293
0.68
6
2.8
20020827
0.04361449
0.03795188
1.63
6
2.91
20020827
0.03864539
0.0306212
0.95
2
1.64
20020827
0.03823617
0.03488836
1.6
2
1.77
20020827
0.1161209
0.1642139
0.17
47
43.3
20020827
0.1389452
0.2062893
227
217
Secchi Disk Depth Relationship
ln Band3 Reflectance / ln Secchi Disk Depth Measurement
Lake Waikare Secchi Disk Depth
Predicted Secchi Depth
ln B3 ln SchiDisk
Measured Secchi Depth
1.4
2
1.2
y = -1.200x - 4.146
R² = 0.650
ln SchiDisk
0
-1
ln SchiDisk
-2
Linear (ln SchiDisk)
Secchi Disk Depth (m)
1
1
0.8
0.6
0.4
-3
0.2
-4
1 July 2008
1 January 2009
1 April 2009
1 April 2009
1 April 2008
1 October 2008
1 July 2008
1 January 2009
1 April 2008
1 October 2008
1 July 2007
1 January 2008
1 April 2007
1 October 2007
1 July 2007
1 January 2008
1 April 2007
1 October 2007
1 January 2007
1 July 2006
1 January 2007
1 April 2006
1 October 2006
1 October 2006
1 July 2005
1 April 2005
1 January 2006
1 October 2005
1 July 2004
1 January 2005
1 April 2004
1 October 2004
1 July 2003
1 January 2004
1 April 2003
1 October 2003
1 July 2002
1 April 2002
1 January 2003
1 October 2002
1 July 2001
1 January 2002
1.0000
1 April 2001
0.0000
1 October 2001
-1.0000
1 July 2000
-2.0000
ln B3 Ref
1 January 2001
-3.0000
1 April 2000
-4.0000
1 January 2000
-5.0000
1 October 2000
0
-5
Predicted Secchi Depth = exp(lnBand3 Reflectance * -1.2004 - 4.1467)
Total Suspended Solids Relationship
Lake Waikare Total Suspended Solids
Band3 Reflectance / Total Suspended Solids Measurement
Predicted Suspended Solids
Measured Suspended Solids
1200
B3 SSDirect
400
350
y = 1153.x - 41.37
R² = 0.820
250
200
SSDirect
150
Linear (SSDirect)
100
600
400
200
0
0.0500
0.1000
0.1500
0.2000
0.2500
0.3000
1 July 2006
1 April 2006
1 January 2006
1 July 2005
1 April 2005
1 October 2005
1 January 2005
1 July 2004
1 April 2004
1 October 2004
1 January 2004
1 July 2003
1 April 2003
1 October 2003
1 January 2003
1 July 2002
1 April 2002
1 October 2002
1 January 2002
1 July 2001
1 April 2001
1 October 2001
1 January 2001
1 July 2000
1 April 2000
0
-50
1 October 2000
-200
50
0.0000
800
1 January 2000
SS Direct
300
Total Suspended Solids mg l-1
1000
450
0.3500
B3 Ref
Total Suspended Solids = Band3 Reflectance * 1153.8 - 41.375
3
1/22/2010
Suspended Solids
Total Suspended Solids
Secchi Disk Depth
Automated
Cloud
Detection
23
4
1/22/2010
Images need to be corrected for atmosphere distortions and sun angle
Remote Sensing Satellite Series & Sensors
•Landsat7 ETM+ Band 3 Corrected Reflectance =
Satellite(s)
First Launch
Sensor(s)
• NOAA 1-18
1970
AVHRR, AVHRR2, AVHRR3
•LHaze = HLmin - L1%
or
LHaze = (Lmin + Lowest DN * (Lmax - Lmin) / 254) - ((0.01 * 1551 * cos(Sun angle * 3.141592 / 180) ** 2)
/ (S-E Distance ** 2 * 3.141592)
• Landsat 1-7
1972
MSS, TM, ETM+
• Resurs-O1 N1-4
1985
MSU-E, -S, -SK
• SPOT 1-5
1986
HRV, HRVIR, HRG
•Radiance = % (Lmax - Lmin) / (Qcalmax - Qcalmin)) * (Band3 DN - Qcalmin) + Lmin)
• IRS 1A,B,C,D/P3,6
1988
LISS-I, -II, -III, -IV, WiFS, AWiFS
•Corrected Reflectance = (3.141592 * (Band3 Radiance - LHaze) * S-E Distance²) / (1551 * cos(Sun angle))
• CBERS 1-2
1999
HRCC, IRMSS
• EOS AM/PM-1
1999
ASTER, MODIS
• DMC 1-5
2002
Multispectral
• CartoSAT 1-2
2005
Panchromatic
• WorldView 1
2007
Panchromatic
• GeoEye 1
2008
Pan, Multispectral
• RapidEye 1-5
2008
Pan, Multispectral
((Lhaze + (0.0602325 * Band3 Digital Number – 0.15)) * Pi * S-E Distance ²) / (195.7 * cos(Pi / 180 * (90
– S Elevation)) ²)
*Lmax, Lmin, Qcalmax, Qcalmin and Sun Angle are taken from the image’s metadata information; Sun –
Earth Distance is calculated according to the day of the year
Positioning Geography
Quickbird
SPOT
GIS played an important role in halting the widespread
closure of Geography Departments at US Universities
in the 1980s – (Personal Communications with
Professor David Mark).
The use of images and maps for simple analysis of
relevant issues has widespread appeal to many
students.
Geography teachers need to embrace GIS and
Remote Sensing and ensure that it is part of the
Geography curriculum.
There is a revolution in the use of Geospatial
Information in society.
•Spatial information is estimated to have
added $1.2 billion (0.6% of GDP) to the
New Zealand economy in 2008.
•Other (non-productivity) benefits are
worth a multiple of this.
•A range of barriers to the adoption of
spatial information have limited the
ability to reap additional benefits in New
Zealand.
•Barriers notably include accessing
data, inconsistency in data
standards, and a general lack of skills
and knowledge relating to modern
spatial information technology.
•Had key barriers been removed it is
estimated that New Zealand could have
benefited from an additional $481
million in productivity-related benefits.
Key Principles
•Geospatial information is collected
once and shared
•Geospatial information is easy to
use and understand
•Geospatial information is readily
available
•Geospatial information is protected
5
1/22/2010
Questions ?
6