1. Locating People at Risk
Extents of flood with different
exceedance probabilities
Population with different
probabilities to be affected by flood

2. Population at Risk Annual Probability
Population at Risk (by return
period)
Risk Curve
Interpolated interim Return Periods

3. Application of methodology - Thane District – India
RP Pop Cumulated Pop % Pop
25 662497.78 662497.78 6.0%
50 74338.64 736836.42 6.7%
100 69165.72 806002.15 7.3%
200 79145.58 885147.73 8.0%
1000 186301.29 1071449.02 9.7%
25 years RP 1000 years RP

4. EM-DAT Historical Records Flood

5. EM-DAT Historical Data

6. Are coordinates within
the country boundary?
http://www.geonames.org/search.html?q=tegucigalpa&country=Honduras
http://www.geonames.org/search.html?q=Comayagua&country=Honduras
http://www.geonames.org/search.html?q=Valle de Angeles&country=Honduras
http://www.geonames.org/search.html?q=Choluteca&country=Honduras
Tegucigalpa,-87.20681,14.0818
Choluteca,-87.19083,13.30028
Valle de Angeles,-87.03333,14.15
Comayagua,-87.6375,14.45139
Geocoding historical accidents
YES NO

7. India geocoding of Accidents (~1000 Cases EM-DAT)
Total of 1100 events with a successful matching of 950

8. Cameroon geocoding of Accidents (~50 Cases EM-DAT)
Total of 46 events with a successful matching of 38

9. Colombia geocoding of Accidents (~500 Cases EM-DAT)
Total of 502 events with a successful matching of 475

10. Risk profiling of all 86 WFP countries

11. Honduras geocoding of Accidents (~120 Cases EM-DAT)
High Risk
Historical Records
Medium Risk
Historical Records
No Risk
Precipitation Pattern

12. Precipitation Data (FAO)
AugustJuneJanuary

13. Calculation

14. Comparing historical precipitation patterns and accidents
Peru

15. Correlating Precipitation and Floods Monthly

16. Global CorrelationClasses Cases Percentage Level
>0.9 56 0.49%Very Highly Correlated
0.7-0.9 1381 12.19%Highly Correlated
0.5-0.7 3442 30.38%Moderately Correlated
0.3-0.5 1962 17.32%Low Correlation Significant Correlation 60.38%
<0.3 4488 39.62%Little Correlation Unignificant Correlation 39.62%
tot 11329
0.49%
12.19%
30.38%
17.32%
39.62%
Very Highly Correlated Highly Correlated Moderately Correlated Low Correlation Little Correlation
Percentage of Correlation

17. People at risk for 25 years Return Period (WFP Countries)

18. EM-DAT Historical Data Registered Occurrences

19. Correlation between occurrences and precipitation

20. National Calculations Admin2 Calculations

21. Example Table of all Adm2 calculated values
All GAUL administrative levels codesISO3 All GAUL administrative levels Reliability

22. Database structure
Annual Population at risk
Correlation between precipitation and historical accidents
Registered Flood occurrences (EM-DAT)
WFP country polygons containing ISO,GAUL and GADM codes
Monthly precipitation values (mm) from FAO
Monthly precipitation values normalized (-1/+1)
Ancillary data for assigning countries to WFP operational areas
Annual Population at risk divided by month