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Short title: landprob

Inputs: DEM in metric projection, Source Landslide areas, H/L value as stopping parameter.
Outputs: pq_limi and all other parameters as described in Gruber et al., 2008 article in the Geomorphometry book.

Purpose and use:

Computes Landslide probabilities — generate landslide probabilities areas using a DEM according to Gruber et al 2008. &r landslide1 <sourcearea\_dem> {h/l stopping value}

Programming environment: Arc AML
Status of work: Public Domain
Reference: Geomorphometry: Concepts, Software, Applications Data set name: Baranja hill

Attachment:

landslide_probabilities.zip

Short title:flowMag.lsc

Inputs:A DEM (the Baranja Hill 25m DEM is used as an example).
Outputs:A raster containing flow magnitude values for the DEM and a raster containing drainage basins.

Purpose and use:

Script to calculate flow magnitude and drainage basins from a DEM. It demonstrates how recursive function calls in LandScript can be used to calculate zonal geomorphometric parameters using map algebra. To use this script, start LandSerf 2.3 or above and then open the LandScript editor (menu: Edit->LandSctipt Editor).
Part of this script appears in Chapter 14 of Hengl and Reuter (2008) [the Geomorphometry book]. This script runs slowly so is better as a demonstration of how recursive function calls can be made in LandScript rather than a production quality flow magnitude calculator.

Programming environment:Landserf
Status of work:Public Domain
Reference: Geomorphometry: Concepts, Software, Applications
Data set name: Baranja hill

Attachment:

flowMag.lsc_.zip

Short title:importData.lsc

Inputs:Baranja Hill data (DEM25m.asc, DEM25srtm.asc, orthophoto.asc).
Outputs:LandSerf files of the input files plus a difference map of the two DEMs.

Purpose and use:

LandScript to import Baranja Hill data and convert to LandSerf format. This script is also included in Chapter 14 of Hengl and Reuter (2008) [the Geomorphometry book]

Programming environment:Landserf
Status of work:Public Domain
Reference: Geomorphometry: Concepts, Software, Applications
Data set name: Baranja hill

Attachment:

importData.lsc_.zip

Short title: characteristicScale.lsc

Inputs: A DEM (the Baranja Hill 25m DEM is used as an example). The name of the parameter to measure and the minimum and maximum window sizes over which to measure it.
Outputs: Two rasters, one containing the measured parameter, the other the window size at which the parameter is most extreme.

Purpose and use:

Finds the scale at which a geomorphometric parameter is most extreme for each cell in a DEM. Part of this script appears in Hengl and Reuter (2008) [the Geomorphometry book].
Script to measure surface parameter at characteristic scales. It is designed to incorporate scale-based analysis into surface parameterisation. It measures the given parameter (e.g. slope, profile curvature etc.) at a range of scales, and finds the scale at which that parameter is most extreme. Can be used to explore scale sensitivity of a surface.

Programming environment: Landserf
Status of work: Public Domain
Reference: Geomorphometry: Concepts, Software, Applications
Data set name: Baranja hill

Attachment:

characteristicScale.lsc_.zip

Maunga Whau (Mt Eden) is one of about 50 volcanos in the Auckland volcanic field. This data set gives topographic information for Maunga Whau on a 10 m by 10 m grid. A matrix with 87 rows and 61 columns, rows corresponding to grid lines running east to west and columns to grid lines running south to north.

Perspective view - volcano

Available layers:

- volcano_maungawhau.asc — the 10 m DEM digitized from the topo map;

Grid definition:

ncols: 61
nrows: 87
xllcorner: 2667400
yllcorner: 6478700
cellsize: 10 m

proj4:+init=epsg:27200

Lineage:

Digitized from a topographic map by Ross Ihaka. These data should not be regarded as accurate.

\> data(volcano)
>library(spatstat)
>LLC <- data.frame(E=174.761345, N=-36.879784)
>coordinates(LLC) <- ~E+N
>proj4string(LLC) <- CRS("+proj=longlat +datum=WGS84")
>LLC.NZGD49 <- spTransform(LLC, CRS("+init=epsg:27200"))
>volcano.r <- as.im(list(x=seq(from=2667405, length.out=61, by=10),
+     y=seq(from=6478705, length.out=87, by=10), 
+     z=t(volcano)\[61:1,\]))
>volcano.sp <- as(volcano.r, "SpatialGridDataFrame")
>proj4string(volcano.sp) <- CRS("+init=epsg:27200")
# str(volcano.sp)
# spplot(volcano.sp, at=seq(min(volcano.sp$v), max(volcano.sp$v),5),
+    col.regions=topo.colors(45))
>write.asciigrid(volcano.sp, "volcano\_maungawhau.asc", na.value=-1)

Data owner: LINZ
Location:Volcano Maungawhau, Auckland, New Zealand
36° 50’ 50.586” S,174° 45’ 56.646” E
See map: Google Maps

Attachment:
volcano_maungawhau.zip