GIS Technical Annexes for DRR CCA

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M ANUAL

FOR

M AINSTREAMING DRR/CCA

IN

P ROVINCIAL D EVELOPMENT

AND

47

P HYSICAL F RAMEWORK P LANS

Specify value as the field

Input raster to be converted

Untick the simplify polygon option

13.You can dissolve your dataset, create a new field (text with 50 characters) and manually type the PEIS text description for future reference. Create a raster layer in ArcGIS for liquefaction and earthquake induced landslide map Similar to the PEIS map, the liquefaction and earthquake induced landslide map can also be converted to vector but differs in the reclassification of pixel values. The succeeding steps are applicable for converting liquefaction and earthquake induced landslide exceedance values to a polygon shapefile format. 1. The conversion of grd format REDAS maps for liquefaction and Ear thquake induced landslide exceedance values follow a similar procedure. The difference will be that unique exceedance values will be retained. First impor t the lique_1.grd or EIL_1.grd file using the MakeNetCDF Raster Layer.

specify filename and location

2. Convert the raw raster file to an imagine image raster (use lique1.img and EIL_1.img). 3. Change the symbology of the *.img file by going to the table of contents > right click the layer (lique1.img or EIL_1.img) > properties > symbology tab. 4. In the symbology tab,click classified > change the number of classes to four (4) > click classify. You will notice a classification calibration window. 5. In the Method drop down menu, select Manual > navigate to the break values window pane > highlight and select the first value > type in -0.25 (this will create a group with values less than or equal to -0.25 representing the high exceedance value range)> highlight the second value > type in -0.15 (this will create a group with values more than -0.25 but less than -0.15 representing the moderate exceedance value range) > highlight the third value and type in


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