1. Spatial Multi Criteria Evaluation for Vulnerability Assessment
Cees van Westen
United Nations University – ITC School for Disaster Geo-Information Management
International Institute for Geo-Information Science and Earth Observation (ITC)
Enschede, The Netherlands
Associated Institute of the
ISL 2004
Introduction to GIS

2. This week Today: Presentations of hazard assessment exercises
Afternoon: SMCE
Wednesday: participatory GIS
Thursday: physical vulnerability assessment
Friday: quantitative risk assessment

3. Presentations
Erosion from Pyroclastic flow deposits: case study Pinatubo (Raphael Spiekermann)
Flood hazard assessment using 2D flood propagation model outputs (Sandra Traper)
Bangladesh SPOT multi temporal flood mapping (Stefan Premm)
Modelling of Land Subsidence & Sea level rise in Semarang city, Indonesia (Tobias Grau)
Landslide susceptibility assessment using statistical method (Ekrem Canli)
Deterministic landslide hazard assessment (Bernd Loigge)
Seismic hazard assessment

4. Framework Input data Susceptibility Initiation Runout
Hazard assessment
Vulnerability
Risk assessment
Quantitative
Qualitative

5. Spatial Multi Criteria Evaluation

6. SMCE Spatial Multi Criteria Evaluation.
You can combine all types of data
Define goal & subgoals
Select indicators
Make a decision tree
Standardize
Weighting
Combination
Classification
ISL 2004
Introduction to GIS

7. SMCE process Identification of the main goal.
Identification of a hierarchy of sub goals.
Identification of criteria or effects, which measure the performance of the sub goals.
Creating and filling a criteria tree, which represents the hierarchy of the main goal, any sub goals, and the criteria.
Identification of alternatives to be evaluated.
Assignment of input maps to criteria for each alternative.
Determination of a standardization method per criterion.
Weighing of criteria in the criteria tree.
Calculation of the Composite Index maps and visualization.
Classifying or slicing the Composite Index maps and visualization.
Calculation of Shape Index and/or Connectivity Index.
ISL 2004
Introduction to GIS

8. Spatial Multi Criteria Evaluation
Composite multi- hazard risk index for Cuba at national scale.
Spatial indicators.
Hazard index
Vulnerability index

9. FACTOR INDICATOR CATEGORY CH W
Socioeconomic status
Livelihood
(0.396)
Labourers (% of unit)
Informal workers (% of unit)
Formal workers
Skilled & highly educated workers
Transferences from outside areas B+ C-
0.48
0.29
0.11
0.04
0.07
Income level
Families Below Food Threshold (% unit)
Families Below Poverty Threshold
Families Above Poverty Threshold
0.61
0.28
Dependency ratio
(0.117)
1 to 1 (% of unit)
2 or 3 to 1
4 to 1
5 or more to 1
0.06
0.12
0.26
0.56
Family size
(0.07)
Less than 5 residents (% of unit)
6 to 10
11 to 15
More than 15
Housing
House type
(0.55)
Reinforced Brick-Concrete (% of unit)
Semi-Concrete
Light materials class 1
Light materials class 2
Light Materials class 3
0.03
0.13
0.53
Land ownership (0.45)
Owned (% of unit)
Rented-tenancy
Squatted, illegal occupation
0.27
0.67
Facilities
Access to drinking water
(0.60)
Private faucet (% of unit)
Shared faucet
Buy to Private Faucet
Public faucet and Pump
Public Pump
0.09
0.15
0.30
0.42
Sanitary facilities
(0.40)
Water sealed unit (% of unit)
Shared unit
Open pit
Public toilet
Other
0.02
0.17
0.57
Environmental quality of surroundings
Waste disposal (0.40)
Number of garbage accumulation spots
0.40
stagnated waters (0.60)
Percentage of the unit perennially occupied by stagnated waters
0.60
Economic opportunities
Topographic elevation of facilities with economic importance
(0.67)
Commercial activities
Transport-related activities
Mixed residential-small businesses
Agriculture
0.21
0.10
0.05
Topographic elevation of Road Network
(0.33)
Main road
Secondary road
Pathways
0.62
Community Capacities
Topographic elevation of Facilities with social importance for the community
(0.15)
Health services
Institutional services
Educational services
Religious services
Areas for recreation
Open spaces for institutional services
0.41
0.20

10. Indicators 1. Generic social vulnerability indicators:
Percentage of young children
Percentage of elderly people
Percentage of minority groups
Percentage of single parent households
Percentage of households living below poverty level.
Literacy rate
2. Hazard specific social vulnerability indicators
people located in flood risk zones, both a daytime and nighttime scenario
people located in landslide risk zones, both a daytime and nighttime scenario
people located in technological risk zones, both a daytime and nighttime scenario
people located in seismic risk zones, both a daytime and nighttime scenario
3. Hazard specific physical vulnerability indicators
buildings located in flood risk zones, with different return periods
buildings located in landslide risk zones, with different degree of susceptibility to landslides
buildings located in technological risk zones, with different degree of susceptibility to landslides
buildings located in seismic risk zones, with different intensities and return periods
4. Capacity indicators
Distance to Evacuation sites
Distance to hospitals.
Awareness
ISL 2004
Introduction to GIS

11. Input data
This exercise uses the results of the loss estimation exercises done earlier for landslides, floods, earthquakes and technological hazards.
ISL 2004
Introduction to GIS

12. Different levels of aggregation
Districts
Wards
Census tracts
Mapping units
City blocks
Basic units for risk
Building footprints
Unemployment
Literacy rate
ISL 2004
Introduction to GIS

13. Indicators 1. Generic social vulnerability indicators:
Percentage of young children
Percentage of elderly people
Percentage of minority groups
Percentage of single parent households
Percentage of households living below poverty level.
Literacy rate
ISL 2004
Introduction to GIS

14. Indicators 2. Hazard specific social vulnerability indicators
people located in flood risk zones, both a daytime and nighttime scenario
people located in landslide risk zones, both a daytime and nighttime scenario
people located in technological risk zones, both a daytime and nighttime scenario
people located in seismic risk zones, both a daytime and nighttime scenario
ISL 2004
Introduction to GIS

15. Steps in the exercise
Step 1: Generation in SMCE of a criteria tree for Generic Social Vulnerability Indicators, with the groups of factors.
Step 2: Generation in SMCE of a criteria tree for Hazard specific social vulnerability indicators, with the groups of factors related to population affected by earthquakes, landslides, flooding and technological disasters in a daytime, and nighttime scenario.
Step 3: Generation in SMCE of a criteria tree for Hazard specific physical vulnerability indicators, with the groups of factors related to buildings affected by earthquakes, landslides, flooding and technological disaster scenarios.
Step 4: Generation in SMCE of a criteria tree for Capacity indicators, which in this case are the distance to emergency centers (e.g. hospitals or fire stations) and the level of awareness.
Step 5: Combination of the 4 sets of indicators into an overall vulnerability indicator.
ISL 2004
Introduction to GIS

16. SMCE process Identification of the main goal.
Identification of a hierarchy of sub goals.
Identification of criteria or effects, which measure the performance of the sub goals.
Creating and filling a criteria tree, which represents the hierarchy of the main goal, any sub goals, and the criteria.
Identification of alternatives to be evaluated.
Assignment of input maps to criteria for each alternative.
Determination of a standardization method per criterion.
Weighing of criteria in the criteria tree.
Calculation of the Composite Index maps and visualization.
Classifying or slicing the Composite Index maps and visualization.
Calculation of Shape Index and/or Connectivity Index.
ISL 2004
Introduction to GIS

17. The criteria tree
ISL 2004
Introduction to GIS

18. The criteria tree
ISL 2004
Introduction to GIS

19. Spatial multi-criteria analysis
A criteria tree contains all criteria
Factors: a criterion that contributes to a certain degree to the output
Benefits
contributes positively to the output; the more you have (the higher the values), the better it is
Costs
contributes negatively to the output; the less you have (the lower the values), the better it is
Constraints: criterion that determines in the calculation of the main goal .Mask out area
ISL 2004
Introduction to GIS

20. Criteria tree: Generic Social Vulnerability
Generate Criteria Tree:
Factors: Age related, Income Related, Ethnicity related, Social structure
Link with attributes in tables
Standardization
Weighting
Optional: constraint
ISL 2004
Introduction to GIS

21. Standardization of criteria
Maximum: The input values are divided by the maximum value of the map
Interval: Linear function with the maximum and minimum values of the map
Goal: Linear function with a specified maximum and minimum values
Piecewise linear: Linear function with two breaking points located between the extremes
Convex: Convex function with one user defined value to re-shape the curve
Concave: Concave function with one user defined value to re-shape the curve
U-Shape: U-shape curve with one user defined value to stretch or shrink the curveGaussianBell-shape curve with one user defined value to stretch or shrink the curve
ISL 2004
Introduction to GIS

22. How to select weights? Direct estimation by expert
The user has to specify weight values him/herself. These user-defined weights are automatically normalized
Pair-wise comparison
With a pairwise comparison matrix, each variable (or criterion) is compared to all others in pairs in order to evaluate whether they are equally significant, or whether one of them is somewhat more significant / better than the other for the goal concerned
Ranking method
the criteria and variables are simply ranked according to their importance as landslide controlling factors
Source: ILWIS Multi Criteria Evaluation
ISL 2004
Introduction to GIS

23. Criteria tree
ISL 2004
Introduction to GIS

24. Criteria tree: Physical Vulnerability & capacity
ISL 2004
Introduction to GIS

25. Final combination
The overall vulnerability indicator is made by combining the four indicator that we have calculated thus far:
A. Generic_Social_Vulnerability (exercise 8.1)
B. Population_Vulnerability (exercise 8.2)
C. Physical_Vulnerability (exercise 8.3)
Capacity (exercise 8.4)
Combine A,B,C with SMCE
Final Vulnerability := Vulnerability / Capacity
ISL 2004
Introduction to GIS