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Knowledge mining tools and strategies for
hypertemporal remote sensing data sets
ESA-EUSC 2008 Conference
Thomas Udelhoven Centre de Recherche Public
Gabriel Lippmann (Luxembourg) Marion Stellmes,
Joachim Hill Trier University, Remote Sensing
Department (Germany)
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Introduction
Syndromes
TSA-Methods
Summary
Results
Objectives

• Framework developed in the context of the
  DeSurvey project
• Distinguishing between climatic or human induced
  changes in surface conditions
• To relate regions with increasing and decreasing
  plant productivity to a process (e.g.
  degradation/recovery)
• Performance evaluation of mitigation programmes
• Early warning of disturbance
• Low cost, replicable, multi-scale

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Introduction
Syndromes
TSA-Methods
Summary
Results
Data
Mediterranean Extended Daily One-Km AVHRR Data
Set (MEDOKADS) of the Free University of
Berlin Bolle et al. 2006 Koslowsky et al.
1998 Calibrated daily, 10-day and monthly AVHRR
composites (1989-present)
Derived Layers NDVI, GVF
Green Vegetation Abundance (GVF)
soil
Ts
Ts
soil abundance
vegetation
cold abundance
cold
NDVI
NDVI
Nemani, 1993 Sandholdt et. al., 2002 Sommer
1999 Stellmes, Sommer Hill, J. 2005
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Introduction
Syndromes
TSA-Methods
Summary
Results
Software (TimeStats)
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Introduction
Syndromes
TSA-Methods
Summary
Results
Problem
Fancy statistics provides only limited
information about underlying processes at the
coarse scale
Trend NDVI
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Introduction
Syndromes
TSA-Methods
Summary
Results
Solution synoptical view of different TSA
products
Trend map
Hot-spot Damaskus Ghouta (1km AVHRR Daten)
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Introduction
Syndromes
TSA-Methods
Summary
Results
Augmented Dickey-Fuller test
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Introduction
Syndromes
TSA-Methods
Summary
Results
The SYNDROMES approach
The basic idea behind syndromes is not to
describe Global Change by regions or sectors, but
by archetypical, dynamic, co-evolutionary
patterns of civilisation-nature interactions "
Petschel-Held et al. 1999, Downing Lüdeke
2002 The syndrome approach considers bundles of
interactive processes which appear repeatedly and
widely spread in typical combinations
Related work Schellnhuber et al. 1997,
Cassel-Gintz Petschel-Held 2000, Petschel-Held
Lüdeke 2000, Geist 2005, Geist Lambin 2004
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Introduction
Syndromes
TSA-Methods
Summary
Results
The SYNDROMES approach
Syndromes of Environmental Degradation with
Relevance to Global Desertification
modified after Lüdeke et al. 2004, Downing
Lüdeke 2000
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Introduction
Syndromes
TSA-Methods
Summary
Results
The SYNDROMES approach
Other Syndromes of Environmental Degradation with
Relevance to Mediterranean Desertification
modified after Lüdeke et al. 2004, Downing
Lüdeke 2000
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Introduction
Syndromes
TSA-Methods
Summary
Results
Time series
parameter
veg. cover
peaking time
magnitude
ADF test
semiannualcycle sign.?
magn. gt TH
condition
trend and significance
y
n
Combination
Syndromes
NDVI rainfall
Additional layers
Validation
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Introduction
Syndromes
TSA-Methods
Summary
Results
Syndromes combining TSA-results
- o
- o
- o
Vegetation Change
Shift in peaking time
Change of Magnitude
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Introduction
Syndromes
TSA-Methods
Summary
Results
Stratum Agriculture CORINE1990
Irrigated Crops
Annual Crops
Permanent Crops (trees etc.)
Pastures
o o o o
o

• o o
• - - o

o o o
- o o - - o
- o o
- o o
reduced pro-ductivity or area
under-grazing
reduced pro-ductivity or area, salinisation
over-grazing
reduced pro-ductivity or area
expansion of irrigated land
excessive ground water consumption high
pesticide input
Overexploitation La Mancha Syndrome
Urban Sprawl Valencia Syndrome
Rural Exodus Pyrenees Syndrome

• - o
• o - o

o o o
Increased Productivity
Increased Productivity
o o
o o
Crop Change
Extensifi-cation.
o o - o - o
Crop Change
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Introduction
Syndromes
TSA-Methods
Summary
Results
Syndrome Map Stratum Agriculture (GVF)
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Introduction
Syndromes
TSA-Methods
Summary
Results
Stratum Natural Vegetation Systems CORINE1990
Forests
Sparsely Vegetated, Bare Rock, Grasslands
Transitional Woodlands, Sclerophyllous
o o o
o o o
o o o

• o o

• - o o
• - o

• - o o
• - o

ADF
ADF
wood extraction
wood extraction
fire
increasing fire risk hydrological change
fire
increasing fire risk hydrological change
Overexploitation
Rural Exodus Pyrenees Syndrome
DISASTER
o o o o o o -
Structural Change, Species Composition
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Introduction
Syndromes
TSA-Methods
Summary
Results
Syndrome Map Natural Vegetation Systems (GVF)
References Begueria et al. (Ambio 2003),
Taillefumier Piégay (Catena 2003), López-Moreno
et al. (Environmental Management 2004), dAngelo
et al. (Catena 2000), Grove Rackham (2001),
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Introduction
Syndromes
TSA-Methods
Summary
Results
Syndrome Map Natural Vegetation Systems (GVF)
Rural Exodus (depopulation of rural areas,
increasing vegetation cover, reduced
accessability of formerly used wood- and
shrublands, increasing wildfire risk, change of
hydrological systems with implications to run-off
and ground-water recharge) Intensification of
agricultural systems (excessive water
consumption in irrigation areas, high chemical
and pesticide input, negative implications on
biodiversity and functioning of connected
ecosystems)
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Introduction
Syndromes
TSA-Methods
Summary
Results
Additional techniques Distributed Lag Models
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Introduction
Syndromes
TSA-Methods
Summary
Results
Distributed Lag Models
Generalized Least-Square approach (after Shumway
and Stoffer, 2000) used in distributed lag models
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Introduction
Syndromes
TSA-Methods
Summary
Results
Distributed Lag Models
Regression of NDVI, rainfall and temperature data
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Introduction
Syndromes
TSA-Methods
Summary
Results
Augmented Dickey-Fuller test
H0 ? 0
Annual cycle removed
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Introduction
Syndromes
TSA-Methods
Summary
Results
Land-cover classification
 Decision fusion  of hypertemporal AVHRR-Data
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Introduction
Syndromes
TSA-Methods
Summary
Results
Land-cover classification
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Introduction
Syndromes
TSA-Methods
Summary
Results
Land-cover classification
Related work Roura-Pascual,N, Pons, P., Etienne,
M. and Lambert, B. (2005)  Transformation of a
Rural Landscape in the Eastern Pyrenees Between
1953 and 2000. Mountain Research and Development,
25, 252-261
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Introduction
Syndromes
TSA-Methods
Summary
Results
Land-cover classification
Overexploitation of the Aquifer 23 (La Mancha)
In the early 1990s, the ground water table of the
aquifer has fallen by almost 40 metres compared
to the situation in the 1950s (Ortega et al.
2002 Baldock, et al., 2000).
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Introduction
Syndromes
TSA-Methods
Summary
Results
Land-cover classification
Shift of the annual green-peak
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Introduction
Syndromes
TSA-Methods
Summary
Results
Summary, conclusions and perspectives

• The SYDROMES concept provides a relevant
  contribution to objective and formalised spatial
  assessment concepts
• Iberia shows only limited areas of
• desertification-related syndromes, large
• parts of Mediterranean Europe are expected
• to behave similarly
• Mapping results relate to a specific time-period
• (1989-2004), scale is 1x1 km2
• Syndromes are prone to change (climatic
• change projections)
• Perspectives combination with ecological land
• quality assessments
• Possible Improvements
• - discrete vz. fuzzy decision rules in TS
  indicator evaluation
• - combine TS indicators with aridity index and
  terrain variables (DEM)

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Thank you!
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