a.Clipping rasters to the study area

165.a.1Creating a polygon of the DEM area

1. 
   Select Vector
   

167.Select Polygon from layer extent and fill in the parameters as indicated in Table 8..

Table 8. Input parameters for Polygon from layer extent for creating polygon of the study area

Parameter	Input
Input layer	png_dem_UTM (load onto canvas first)
Output polygon shapefile	study_area.shp (in base_data)
Add result to canvas	Check box indicated

167.a.1Rainfall

1. 
   Select Raster
   

169.Select Clipper and fill in the parameters as indicated in Table 8..

Table 8. Input parameters for Clipper used to clip rainfall raster to study area

Parameter	Input
Input file (raster)	Rainfall_sim_UTM.tif
Output file	rf_study_area.tif (in processing)
No data value	255 (and check box indicated)
Clipping mode	Mask layer (Check box indicated)
Mask layer	study_area
Load onto canvas when finished	Check box indicated

gdalwarp -dstnodata 255 -q -cutline C:/Training/base_data/study_area.shp -crop_to_cutline -of GTiff C:\Training\base_data\rainfall_sim_UTM.tif C:/Training/processing/rf_study_area.tif

170.Press OK.

170.a.1Geology

1. 
   Select Raster
   

171.Select Extraction

172.Select Clipper and fill in the parameters as indicated in Table 8..

Table 8. Input parameters for Clipper used to clip geology raster to study area

Parameter	Input
Input file (raster)	geology_sim_UTM.tif
Output file	geo_study_area.tif (in processing)
No data value	255 (and check box indicated)
Clipping mode	Mask layer (Check box indicated)
Mask layer	study_area
Load onto canvas when finished	Check box indicated

gdalwarp -dstnodata 255 -q -cutline C:/Training/base_data/study_area.shp -crop_to_cutline -of GTiff C:\Training\base_data\geology_sim_UTM.tif C:/Training/processing/geo_study_area.tif

173.Press OK.

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