RISK ASSESSMENT AND EVALUATION ArcGIS® toolbox
Contents
1. f following these instructions a b c d e 1 Open the attribute table of the buildings layer Click on Options and then on Select by attributes Double click on the field build Click on the symbol Click on the button Get Unique Values A list of all the buildings materials will appear in the box on the right Double click on the first material of the list for example concrete Figure 4 VULNERABILITY LEVEL 25 26 9 u unknown unknown ected Click on Apply All buildings made of concrete are now selected 0 unknown unknown 0 unknown unknown unknown unknown Enter a WHERE clause to select records in the table window Method Create anew selection 7 Fields Unique Values unknown Build mat concrete ae design concrete wood unknown foundat gt gt others unknown floor wood unknown am Hong unknown n gt unknown D E Not eub 190 unknown d GoTo unknown a x unknown 8 Get Unique Values unknown unknown unknown unknown unknown unknown unknown unknown Options Figure 4 RISK ASSESSMENT AND EVALUATION unknown Close the attribute table i Click on the editor button and choose star2. S so S S S seses 9 9 9 9 9 Oo G RISK ASSESSMENT AND EVALUATION 3 Choose an integer numeric value between 1 and 5 for each impact element where 5 stands for maximum vulnerability and 1 for minimum vulnerability For example the impact element value for building material that is m will be 5 if the structure is made of wood high vulnerability 3 if it is made of bricks mean vulnerability and 1 if it is made of reinforced concrete low vulnerability Suggested impact element s values are listed in Table 1 VULNERABILITY LEVEL 23 Suggested impact element s value ELEMENT 1 2 3 4 5 Reinforced Bricks or wood Wood di concrete concrete Open plan without Open plan with No open plan 9 movable objects movable objects E 5 stories 4 stories 3 stories 2 stories 1 story t deep pile mean foundations surface spread foundations foundations d long building side long building side long building perpendicular to oblique to the side parallel to the coast line coast line le coast line 24 Table 1 RISK ASSESSMENT AND EVALUATION 4 Put the numeric value chosen for each impact element in the relative field 5
3. unkown material assign them the maximum impact element s value that is 5 Repeat all changing impact element at line c Finally you will obtain an attribute table looking like the one in Figure 8 RISK ASSESSMENT AND EVALUATION Figure 8 VULNERABILITY LEVEL 33 34 Calculate the vulnerability level of every building a Stop editing clicking on Editor and select Stop editing b Open the buildings attribute table and click on Options then choose Add field In the window that appears type BV1 in the box and select Float in the Type box Then put both precision and scale equal to 2 Figure 9 Click OK RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL Add Field Figure 9 35 36 d e 1 Restart editing In the attribute table select the BV1 field clicking on the name of the field Right click on the field name BV1 in the attribute table and select Calculate values Figure 10 RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL RR 9 floor Figure 10 37 9 Insert the relation for the computation of the building vulnerability level in the box under 1 The relation is BV1z 0 234 0 333 g 0 211 s 0 089 d 0 133 f Click on m g s d f in the Fields box and on the mathematical operators buttons to insert them in the relation above Figure 11 This relation com
4. Hz4 Where stands for the hazard level H will be used in the computation of the risk level Using GIS software these four intervals have been plotted on an hazard map identifying 4 different areas Figure 17 66 RISK ASSESSMENT AND EVALUATION HAZARD LEVEL EB mu 0 05 1 Cm GM ES me 1 Figure 17 Hazard map of the Khao Lak study area Thailand HAZARD MAPPING 67 Users can obtain an approximated evaluation of the hazard map imaging that the study area will be flooded until the topography level curve having the same height of the Tsunami wave on the coast line In this way users can calculate the maximum water level reached in each position of the study area as the difference between the Tsunami wave height on the coastline and the ground topographic elevation in that point inland 68 RISK ASSESSMENT AND EVALUATION 4 RISK LEVEL As previously stated the numeric value of risk can be calculated as the product between vulnerability and hazard level Since vulnerability level ranges from 1 to 5 and hazard level ranges from 1 to 4 risk level of each vulnerable element will be given by R VxH 4 R must be an integer number ranging from 1 to 5 where 5 stands for the maximum risk level Once risk level has been calculated it will be possible to plot it on a risk map using a GIS software The following paragraph shows how to create a risk map for the built environment v
5. Total Total weight m weight g weight s weight d weight f Structural 0 178 0 222 0 045 0 089 0 133 damage Damage 0 056 0 111 0 166 0 0 given to flooding TOTAL 0 234 0 333 0 211 0 089 0 133 NB Total weight of each impact element in respect to both criteria is calculated as product between the criterion weight and the relative weight of the impact element considered Final calculation of building vulnerability will be then given by built environment 0 234 m 0 333 g 0 211 s 0 089 0 1331 14 RISK ASSESSMENT AND EVALUATION Single values of impact elements 0 s d f are ranging between 1 and 5 as previously stated This method could be applied to any of the other vulnerability parameters Once vulnerability level is calculated it will be possible to insert these values in a vulnerability map Next paragraph describes how to create a built environment vulnerability map using GIS software The method shown can be applied also to all others vulnerable parameters VULNERABILITY LEVEL 15 2 2 TUTORIAL Creating a built environment vulnerability In this paragraph we present a list of all the steps required to create a built environment vulnerability map of the study area using the ArcGis ArcMap 9 0 software by ESRI The aim is to assign to each building in the pilot area a vulnerability level value as an integer number between 1 and 5 The CD Rom included with the manual contains all the files needed to perf
6. element a e g a given building belonging to the vulnerability parameter A e g the built environment w weighting coefficient e vectorial value estimated for the impact element n total number of impact elements related to the parameter A VULNERABILITY LEVEL 7 21 Multi criteria analysis Multi criteria analysis is a decision making process CRATER team experts have optimized this technique and applied it for the first time to a vulnerability problem Outcome of the multi criteria analysis are the weighting coefficients w of the relation 1 The practical example given below in which multi criteria analysis is applied to the built environment vulnerable parameter would help the understanding of this process First step to identify the impact elements that need to be weighted Impact elements Building material m e Description of ground floor g e Number of stories s 8 RISK ASSESSMENT AND EVALUATION Design d e Foundations f Second step identify the weighting criteria Weighting Criteria Structural damage e Damage given to flooding Weighting criteria are identifying the type of damage the parameter would be subject to VULNERABILITY LEVEL Third step is a pair wise comparison between weighting criteria Structural Damage Fictitious Total Weight damage given to factor 2 Total 3 flooding Structural damage 1 1 2 0 667 Damage given to 0 1 1 0 333 flooding Fi
7. income 2 4 Creating a Socio Economic Aspects vulnerability map Expressed in the simplest terms a disaster affects assets direct damages and the flow for the production of goods and services indirect losses ECLAC 2003 In this way socio economic aspects can suffer both direct and indirect damages Only vulnerability to direct damages can be plotted on maps because indirect damages are not linked to any particular location on the territory Indirect damages must be considered from a qualitative descriptive point of view A direct damages vulnerability map can be created following the method presented above VULNERABILITY LEVEL 55 For buildings the only socio economic impact element is the buildings use The relation 1 is reduced to SEV Socio Economic Vulnerability 2 e x BV 5 where e is the value given to the impact element building use Suggested values for e are shown in the following table 56 RISK ASSESSMENT AND EVALUATION Socio economic vulnerability of buildings Building use 2 PUBLIC HEALTH EDUCATION DRINKING WATER AND SANITATION TRANSPORTS ENERGY INDUSTRY AND COMMERCIAL AGRICOLTURE AND LIVESTOCK TOURISM AUTHORITIES RELIGIOUS HISTORICAL N O O LIVING HOUSE VULNERABILITY LEVEL 57 For land use the relation 1 becomes SEV Suggested e values for land use are shown
8. 5 new fields short integer in the attribute table of buildings shape file one for each impact element and call them m for the building material g for description of ground floor e 5 for the number of stories 18 RISK ASSESSMENT AND EVALUATION e d for the design e f for the foundations Each of these fields must be filled with the impact elements value that will be introduced at step 3 To create a new field a Open the buildings attribute table and click on Options then choose Add field Figure 1 VULNERABILITY LEVEL 19 20 Create Graph Add Table to Layout Figure 1 RISK ASSESSMENT AND EVALUATION b In the window that appeared type in the box and select Short Integer in the Type box then click Figure 2 wood wood Add Field Name Type Short Integer Field Properties Precision wood wood Figure 2 VULNERABILITY LEVEL 21 c Do the same for g s d P obtaining Figure 3 Attributes of Buildings 0 unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown 0 unknown unknown unknown unknown unknown unknown 0 unknown Figure 3 jejejeje
9. 61 Figure 22 RISK LEVEL Delete Field 79 13 Insert the relation for the computation of the building risk level in the box under R1 The relation is BV HAZARD 4 Click on BV MAX and on HAZARD in the Fields box and on the mathematical operators buttons to insert them in the relation above Figure 23 80 RISK ASSESSMENT AND EVALUATION RISK LEVEL Field Calculator BV MAX HAZARD 24 Figure 23 81 14 Click Ok In the field R1 you have just calculated the risk level of each building but not as integer numbers Figure 24 In order to obtain integer numbers you must approximate them all 7 meas in on on in in cn Lr atl Ls m 4 L on n n n e enl enl on en en en en on en en in in en on n n nn on cn niu cn en gt Figure 24 82 RISK ASSESSMENT AND EVALUATION 15 Close the attribute table Save your edits and stop editing 16 Open the buildings Intersect attribute table Add a new field and call it RISK MAX short integer 17 Select by attributes Options Select by Attributes all buildings with a R1 value included in the 0 1 interval R1 gt 0 a
10. Asian Disaster Preparedness Center Italian Ministry for the Environment and Territory RISK ASSESSMENT AND EVALUATION ArcGIS toolbox USER S MANUAL CRATER COASTAL RISK ANALYSIS OF TSUNAMIS AND ENVIRONMENTAL REMEDIATION Asian Disaster Preparedness Center Italian Ministry for the Environment and Territory RISK ASSESSMENT AND EVALUATION ArcGIS toolbox USER S MANUAL CRATER COASTAL RISK ANALYSIS OF TSUNAMIS AND ENVIRONMENTAL REMEDIATION Asian Disaster Preparedness Center Italian Ministry for the Environment and Territory Italian Ministry for the Environment and Territory Asin Disaster Lamer Via Cristoforo Colombo 44 P O Box 4 Klong Luang 00147 Roma Italy Pathumthani 12120 Thailand CONTRIBUTING AUTHORS Dr Filippo Dall Osso Alessandra Cavalletti PhD Eng Paolo Polo Contact CRATER info gmail com CONTENTS 1 Tsunami vulnerability and risk analysis uie ini een irr iene e i 1 1 1 Ja NA oe 1 2 NMulnerability 5 21 MultesriterianalysiS suo pape etd oque 8 2 2 TUTORIAL Creating a built environment vulnerability 16 2 3 Creating a population vulnerability 50 2 4 Creating a socio economic aspects vulnerability 55 2 5 Creating an environment
11. LNERABILITY AND RISK ANALYSIS 3 RISK ASSESSMENT AND EVALUATION 2 VULNERABILITY LEVEL Vulnerability parameters identifies for the study are population built environment socio economic aspects environment For each of these parameters a list of impact elements have been made Impact elements are those characteristics of the parameter considered that could be mostly affected by the tsunami wave Summation of the impact elements defines the vulnerability of a chosen parameter VULNERABILITY LEVEL 5 For example in the case of built environment the impacts elements building material m description of ground floor g number of stories s design d foundations 4 For every building we assigned a numeric value to each impact elements These values are integer numbers ranging between 1 and 5 where 5 stands for the maximum contribution given by the impact element to the total building vulnerability A building made of concrete will a low value of for example m 1 because it is supposed to be more resistant to the Tsunami wave If the building material is wood the value of will be higher for example mz5 As for the impacts elements a level of vulnerability ranging between 1 and 5 has been chosen for each vulnerable parameter 6 RISK ASSESSMENT AND EVALUATION Vulnerability level is given by A Si wi ei fori 1 n 1 Where V A vulnerability level of the
12. al areas a protected areas extent high vulnerability b extent of zones of ecological interest mean vulnerability C extent of agricultural areas low vulnerability Every sub parameter must be divided into a number of reference units for example following the administrative boundaries Reference unit must be imported in the GIS project as a geo referenced polygons shape file For each reference unit you have to calculate the vulnerability level using relation 1 64 RISK ASSESSMENT AND EVALUATION 3 HAZARD MAPPING In the case of a Tsunami risk hazard has been defined as the maximum height of the water column reached in each point of the study area during the flooding of the 26 December 2004 To obtain these values CRATER experts simulated the inundation and the consequential flooding using two different numerical models The first starting from the record of the tide level gauges transferred the waves from offshore to the coast line The second one starting from the waves heights on the coast line simulated the flooding of the study area giving as output the maximum water height reached in each point inland In order to give a prompt vision of how many floors of each building got inundated assuming the height of each floor equal to 3 meters the water height values have been divided in 4 intervals From zero to meters H21 From 3 to 6 meters Hz2 HAZARD MAPPING 65 From 6 to 9 meters Hz3 More than 9 meters
13. at steps 17 to 23 assigning RISK MAX 2 3 4 5 to buildings having R1 respectively included in 1 2 1 gt 1 and BV1 lt 2 2 3 BV1 gt 2 and BV1 lt 3 3 4 1 gt 3 and BV1 lt 4 and 4 5 BV1 gt 4 and BV1 lt 5 intervals 26 Save your edits Now every building in your study area has a Risk level RISK MAX in the attribute table of buildings Intersect layer This value is an integer number between 1 and 5 Figure 27 RISK LEVEL 87 88 Figure 27 RISK ASSESSMENT AND EVALUATION 27 Plot the five risk levels on the assigning different colors to buildings having different risk levels RISK MAX as you did in the case of vulnerability level 28 Your risk map is finished Figure 28 Save your edits RISK LEVEL 89 B risk tut mxd ArcMap ArcView File Edit View Insert Selection Tools Window Help Georeferencing Y Layer aeo thailand pretsunami Qi 2 Constructior Aig ed Style Deus V B a eb 13385 9145 001 71 emm Pilot Area hazard geo thailand kaho lak pretsunami1 jpg CUbPzor it 3u se9 Figure 28 A detail of the buildings risk map of the pilot area 90 RISK ASSESSMENT AND EVALUATION
14. ctitious factor 0 0 0 0 In the matrix above the weighting criteria have been compared with pair wise matches Introduction of aso called fictitious factor is needed for obvious calculation reasons From the above table is clear that in this case a structural damage has more weight than the damage given to flooding RISK ASSESSMENT AND EVALUATION Impact elements are valued among themselves in respect to a single weighting criterion This should give a ranking level of impact element in respect to a given weighting criterion First table below is relative to the structural damage criterion second one to the damage given to flooding Structural m G S f D Fictitious Total Relative damage factor weight Total 15 m 0 1 1 1 1 4 0 267 1 1 1 1 1 5 0 333 5 0 0 0 0 1 1 0 067 F 0 0 1 1 1 3 0 2 D 0 0 1 0 1 2 0 133 Fictitious 0 0 0 0 0 0 0 factor VULNERABILITY LEVEL 11 400000 0 1 1 046000 167 A 0 1 2 0 333 1 A 1 3 Fictitious factor 0 Elements d and t have not been inserted being these elements not related to flooding RISK ASSESSMENT AND EVALUATION Summarizing the above results we obtain Weight of Relative Relative criterion weight m weight g Structural 0 667 0 267 0 333 damage Damage 0 333 0 167 0 333 given to flooding VULNERABILITY LEVEL Relative weight s 0 067 0 5 Relative weight d 0 133 Relative weight f 0 2 Total weight calculation Total Total Total
15. es from the general vulnerability level relation in which weighting factors have been calculated using multi criteria analysis 38 RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL Field Calculator Type Number C String C Date Advanced 0 234 m 0 333 0 211 s 0 089 d 0 133 f Figure 11 39 40 f Click In the field BV1 you have calculated the vulnerability level of each building as a floating number Figure 12 In order to obtain integer numbers you must approximate them all RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL 1 unknown Figure 12 V4 L 41 E 44 E E 4 1 5 L 5 28 L5 44 41 9 Close the attribute table Save your edits and stop editing h Open the attribute table Add a new field called BV MAX short integer i Select by attributes Options Select by Attributes all buildings with a BV1 value included in the 0 1 interval 1 gt 0 BV1 lt 1 You can do this by typing BV1 SO AND BV1 lt 1 Figure 13 Click Apply 42 RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL Enter a WHERE clause to select records in the table window Create new selection Unique Values d D design foundat g floor BV MAX eS Figure 13 43 k h m 44 the atiribute table and Resta
16. happens during the night all the people are inside buildings Son 1 2 BV 10 if the Tsunami happens during the day people are for a half inside buildings and for a half outside If the chosen reference area is bigger than a building for example a village the BV value is the mean of all buildings inside the reference unit Su is a switch taking into account the high tourist season and Su 1 if the Tsunami occurs in high tourist season Su 0 if the Tsunami occurs in low tourist season VULNERABILITY LEVEL 53 S is switch taking into account the low tourist season and S the Tsunami occurs low tourist season S 0 if the Tsunami occurs in high tourist season population vulnerability in High season is the population vulnerability level in the reference unit calculated for high season using relation 1 and the population impact elements listed above PV w density u ws children seniors Invalids u mean Weights must be calculated with multi criteria analysis To calculate weights chose as first the population weighting criteria and follow the example given for buildings vulnerability population vulnerability in Low season is the population vulnerability level in the reference unit calculated for low season 54 RISK ASSESSMENT AND EVALUATION wi density wa gender ws children seniors Invalids mean
17. he smallest reference unit for population is a building but if you don t have population data so detailed you should choose a bigger reference 50 RISK ASSESSMENT AND EVALUATION unit for example a neighborhood or a village or even district according to the resolution of data you have available For every reference unit you must also know High season and low season density Mean time for evacuation Reference unit must be imported in the GIS project as a geo referenced polygons shape file The relation for calculating population vulnerability of a chosen reference unit is PV Population Vulnerability Kg Spn Su PVu Son S PVi Where VULNERABILITY LEVEL 51 is a factor that takes into account the mean time for evacuation of the reference unit chose under the assumption that the launch of the Tsunami alarm would happen 15 minutes before the wave arrival Suggested values of Ke are listed in the following table If the early warning system would be faster or slower you should consequently modify the suggested values Suggested values with a Tsunami alarm 15 minutes Mean time for evacuation before the wave arrival minutes Ke AREA 1 lt 5 0 4 AREA 2 between 5 and 10 0 6 AREA 3 between 10 and 15 0 8 AREA 4 gt 15 1 52 RISK ASSESSMENT AND EVALUATION Spn depends on the time arrival of the tsunami wave day or night and Spn BV 5 if the Tsunami
18. in coastal areas A risk to a natural event is defined as the mathematical product between vulnerability and hazard it refers to the expected loss from a given hazard to a given element at risk Vulnerability is defined as the potential for damage while hazard for a Tsunami event is defined as the wave height Risk management is a two parts process involving risk assessment and risk evaluation 2 RISK ASSESSMENT AND EVALUATION Hisk assessment is mainly a scientific and quantitative exercise out coming from analysis of field and or experimental data e g modeled tsunami wave height and from an overall understanding of the nature of the hazard and of vulnerable parameters UNDP 1994 Hisk evaluation joins perceived risk to a more enlarged qualitative analysis including for example cost benefit trade off and socio economic impact Main vulnerable parameters in the case of a Tsunami event are population built environment infrastructures ecosystem and environment Understanding vulnerability and hazard level identification of possible mitigation measures of the socio economic impact caused by the event and the cost benefit trade off they all give information needed to evaluate the level of risk Decision makers and end users such as local authorities NGO disaster and prevention officers will be able to decide the level of risk and plan which protection level is needed to put in place proposed mitigation measures TSUNAMI VU
19. in the following table 58 RISK ASSESSMENT AND EVALUATION Socio economic vulnerability of land use Building use TRANSPORTS RIVER AND CHANNELS LAKES AND WET LANDS NOT CULTIVATED LANDS AGRICOLTURE ANNUAL CROPS AGRICOLTURE PERMANENT PLANTATIONS BEACH FISHING POOLS Co m VULNERABILITY LEVEL 59 2 5 Creating an Environment vulnerability For a more specific analysis we have divided the Environment into four sub parameters 1 Surface water 2 Ground water 3 Coastal zone 4 Internal areas 60 RISK ASSESSMENT AND EVALUATION Impacts elements 1 Surface water a the river capacity b rainfall evaporation 2 Ground water a presence of low lying areas eroded pockets restricted drainage canals b number of wells C tide effect on rivers mouths VULNERABILITY LEVEL 61 d rainfall evaporation e soil permeability f depth of the aquifer g the hydraulic conductivity of the aquifer 3 Coastal zone a Coastal features sandy beach sandy beach with dunes coast with rocks b Artificial coastal defenses walls behind the beach Topography flat high vulnerability d Wetlands extent protected wetlands 62 RISK ASSESSMENT AND EVALUATION Submerged and intertidal zones features coral reef extent and depth mangroves forests extent Posydonia praires extent VULNERABILITY LEVEL 63 4 Intern
20. nd R1 lt 1 You can do this by typing gt 0 AND R1 21 Click Apply Figure 25 RISK LEVEL 83 Select by Attributes Enter a WHERE clause to select records in the table window Method Create a new selection b Fields Unique Values P By MAX design faundat floor FID hazard HAZARD ES Unique Values SELECT FROM buildings Intersect WHERE Ri 0 AND R1 lt 1 Clear Verify Load Save Figure 25 RISK ASSESSMENT AND EVALUATION 20 21 22 23 RISK LEVEL Close the buildings Intersect attribute table and Restart editing Click on the attribute button on the left of the Target box A new window called attributes will appear Double click on buildings Intersect group in the box on the left In the box on the right click on the R1 field in the Property column The line of the R1 field will be selected Click in the R1 line you have selected under the Value column Type the integer value of 1 and press Enter Figure 26 In this way you have assigned to all buildings with a R1 included in the interval 0 1 a RISK MAX value equivalent to 1 converting all floating numbers in integer and approximating them to 1 85 86 24 Attributes HHE 5 9 d f B V V x Figure 26 RISK ASSESSMENT AND EVALUATION 25 Repe
21. orm the case study simulation Starting Data 1 A geo referenced shape file representing all the buildings of the study area as polygons We will call it buildings This shape for the pilot area is located Buildings Vulnerability tutorial Shapefile 16 RISK ASSESSMENT AND EVALUATION 2 The attribute table of the buildings shape must contain one field for each impact element related to the built environment These impact elements are a b c d e Building material field name Build mat Description of ground floor field name g floor Foundations field name foundat Design field name design Number of stories field name BL NSTOREY You should have data for any impact element for each building The five fields containing the impact elements must be filled with all these data For example if a building is made of concrete the user will have to write concrete in the field Build mat at the line related to that building VULNERABILITY LEVEL 17 In the case that you miss information about any of the impact elements of particular building you just have to write unknown in the relative field at the line related to that building Steps required 1 Open ArcGis ArcMap 9 0 Import all shape files in the Building vulnerability tutorial Shapefile folder and the aerial photo located in the Aerial Photo folder 2 Create
22. p E geo thailand pretsunami1 jpg By 1 buildings N BO HING UD Figure 19 RISK LEVEL 75 gt gt gt gt gt gt gt gt nj e Figure 20 The buildings Intersect attribute table contains both buildings fields and on on amp n Cn T n anj amp n cn on amp n cn n amp n cn n enj enj enj en enj enj enj enj enj enj enj enj enj enj en n oon n on on cn ini on in n enj enj enj enj enj inj on enj on n hazard_map fields RISK ASSESSMENT AND EVALUATION 9 RISK LEVEL Open the buildings Intersect attribute table Add a new field and call it R1 Type Float Field properties Precision 2 Figure 21 Click OK Add Field Name R1 Type Float X Field Properties Precision Scale Scale 2 77 78 10 11 12 Figure 21 Start editing In the buildings Intersect attribute table select the R1 field clicking on the name of the field Right click on the field name R1 in the attribute table and select Calculate values Figure 22 RISK ASSESSMENT AND EVALUATION BV1 FID hazard HAZARD
23. rt editing Click on the attribute button on the left of the Target box A new window called attributes will appear Double click on buildings group in the box on the left In the box on the right click on the 1 field in the Property column The line of the BV1 field will be selected Click in the BV1 line you have selected under the Value column Type the integer value of 1 and press Enter In this way you have assigned to all buildings with a BV1 included between 0 and 1 a BV MAX value of 1 converting all floating numbers into integer and approximating them to 1 RISK ASSESSMENT AND EVALUATION n Repeat steps i to m assigning BV MAX 2 3 4 5 to buildings having BV1 respectively included 1 2 1 gt 1 BV1 lt 2 2 3 BV1 gt 2 and BV1 lt 3 3 4 BV1 gt 3 and BV1 lt 4 and 4 5 1 gt 4 and BV1 lt 5 interval Save your edits Now every building in your study area has Vulnerability level BV MAX in the attribute table of buildings layer This value is an integer number between 1 and 5 Figure 14 VULNERABILITY LEVEL 45 gto nam E i a i a ai ii Figure 14 RISK ASSESSMENT AND EVALUATION 46 6 Plot the 5 vulnerability levels on the map assigning different colors to buildings having different vulnerability levels BV MAX a Right click on the buildings layer in the layer box b Select Propertie
24. s then Symbology In the Show Box select Categories and then Unique values Figure 15 In the value field box select BV and click Add all values All the BV MAX values appear with different colors Click Apply and then Your vulnerability map is finished Figure 16 d Save your project VULNERABILITY LEVEL 47 48 Layer Properties General Source Selection Display Symbology Fields Definition Query Labels Joins 8 Relates Show Draw categories using unique values of one field Import Categories Value Field Color Scheme vwx Unique values many I Maca gambas na smile 77 78 uantities ise al other values all other values Multiple Attributes Heading E 5 Figure 15 RISK ASSESSMENT AND EVALUATION VULNERABILITY LEVEL t Figure 16 49 2 3 Creating a Population vulnerability The method for creating risk and vulnerability maps for population using ArcGis ArcMap 9 0 is the same we presented in the paragraph above Impact elements for population are 1 Density total number of people 2 Number of children senior citizens and invalids 3 Gender number of women 4 Mean income All data about these impact elements must refer to a particular reference unit Population risk and vulnerability will be calculated for this reference unit T
25. t editing Select the buildings layer in the Target box k Click on the attribute button on the left of the Target box Figure 5 A new window called attributes will appear Figure 6 VULNERABILITY LEVEL 27 Spatial Analyst Layer 1 2 New Feature Target 93 E a d Ed it Figure 5 28 RISK ASSESSMENT AND EVALUATION Attributes Sh Ee BB Ee 888 8188 VULNERABILITY LEVEL Figure 6 29 30 Double click on buildings group in the box on the left In the box on the right click on the field in the Property column The line of the m field will be selected Click in the line you have selected under the Value column Type the numeric value you want to assign to the impact element for all buildings made of concrete for example if m21 type 1 Figure 7 RISK ASSESSMENT AND EVALUATION Editor 2 v Task Create New Feature 7 Target Buildings Attributes Figure 7 VULNERABILITY LEVEL 31 9 5 32 Press enter Now all buildings made of concrete have an impact element value equivalent to 1 m 1 Save your edits Click on editor button and choose Save Edits Repeat all from line a choosing the subsequent building material at line f When all building materials have been considered it could remain only some buildings with
26. table reports in the field HAZARD the hazard level value for each polygon Steps required 1 Open ArcGis ArcMap 9 0 Import all shape files present the Building risk tutorial Shapefile folder and the aerial photo located in the Aerial Photo folder of the CD Rom 2 Open the Arc Toolbox RISK LEVEL 71 3 Double click on Analysis Tools 4 Double click on Overlay 5 Double click on Intersect The Intersect window appears 6 Inthe Input Features box select the buildings layer and the hazard layer 7 nthe Output Feature Class box select the folder in which you want the output shape file of the intersection to be saved Figure 18 72 RISK ASSESSMENT AND EVALUATION RISK LEVEL 73 74 Click OK new polygons shape called buildings Intersect appears in your layer s list Figure 19 This shape file is the intersection between buildings shape file and hazard map shape file His attributes table contains both buildings fields and hazard fields Figure 20 RISK ASSESSMENT AND EVALUATION B risk tut mxd ArcView Edit Insert Selection Tools Window Heb Georeferencing Y Layer geo thailand pretsunami v S Construction used 4 X d 14565 uu een Editor x 9 1x o 5 5 Pilot Area a L hazard ma
27. ulnerable parameter The same method allows to calculate the risk level for all others vulnerable parameters RISK LEVEL 69 41 TUTORIAL Creating built environment risk map Now we are going to list all the steps required to create a built environment risk map of the study area using the ArcGis ArcMap 9 0 software by ESHI This tutorial starts from the results given above The main aim is to assign to each building a risk level value as an integer number between 1 minimum risk and 5 maximum risk The CD Rom included with the manual contains all the files needed to perform this tutorial Starting data The risk level of each building is given by the product between vulnerability level and hazard level so data required for creating a buildings risk map are e The buildings shape file obtained resulting from the building vulnerability tutorial In the attribute table of this shape file there is a field called BV MAX reporting the vulnerability 70 RISK ASSESSMENT AND EVALUATION level of each building of the pilot area This shape is located in the Building risk tutorial Shapefile folder with the name of buildings Hazard map of the pilot area Hazard map is a polygons shape file called hazard map located in the Building risk tutorial Shapefile folder Every polygon represents an area with constant maximum water level reached during the Tsunami of December 26 2004 The buildings attribute
28. vulnerability map 60 3 S 65 ME s 69 4 1 TUTORIAL Creating a built environment risk 70 1 TSUNAMI VULNERABILITY AND RISK ANALYSIS 1 1 Introduction The tsunami event occurred on 26th December 2004 in South Eastern Asia caused more than 200 000 casualties along the coasts of Indonesia Thailand Malaysia India Sri Lanka and other countries facing the Indian Ocean Tsunami was initiated by an extremely high magnitude earthquake 9 3 on the Richter scale localized a few kilometers eastward of the Sumatra coasts along the subductive system characterized by the Sunda Arc Because of the presence of this active tectonic margin a new Tsunami event can not be excluded in the future TSUNAMI VULNERABILITY AND RISK ANALYSIS 1 In order to better face any future occurrence of Tsunamis the SAVE module of the CRATER project focuses on the risk analysis method In the last years a number of International and National associations such as UNDP United Nations Development Program NOAA National Oceanic and Atmospheric Administration U S and FEMA Federal Emergency Management Agency U S suggested guidelines for extreme natural events risk analysis CRATER project started from these guidelines and from data gathered after the Tsunami of 26 December 2004 One of the main aims of the CRATER project was to create a complete tool for Tsunami risk analysis
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