Questions tagged [slope]

Use this tag when asking questions related to slope analysis.

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Finding areas with specific slope criteria

I am new to ArcGIS. I clipped a slope raster based on 3 MULTIPART features, and need to find areas where the slope is less than 10 degrees. How do I get fields into a raster layer to then select what ...
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Negative slope in QGIS

How do I use the QGIS slope function to calculate slope and differentiate between uphill and downhill, and produce both positive and negative slopes?
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Calculate slope along line feature for line segments of equal elevation?

I would like to calculate the surface slope of a glacier in the Swiss alps. In ArcGIS Pro this can be done using the Add Surface Information Tool. The output is a data table with the slope for each ...
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Using ArcGIS path distance tool and vertical factor to estimate fuel used by automobile

I am attempting to use the Path Distance tool (either in ArcMap 10.7 or ArcGIS Pro 2.8) to estimate the amount of fuel vehicles need to drive across the landscape. I have the typical gas mileage/fuel ...
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QGIS Raster Hillshade Classic Drawing Texture

I found this drawing of a valley and really like the texture of it. I suppose this is a sort of hachure map drawn with dots. I was wondering if it was possible to recreate something similiar in QGIS (...
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Problem with gdaldem slope -> result is off by some degrees

We are currently having some issues with gdaldem slope. We'd like to create a slope map of a geotiff, but the result seems to be some degrees off to what it actually should be. Our input geotiff is in ...
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Failing to correctly refer to raster layer in Raster calculator (ERROR 000539) using ArcGIS Pro

Here is my function in Raster Calculator: Tan((Raster("MCE: TWI\Slope"))*1,570796/90) MCE: TWI\Slope is the location for my Slope-layer. Looks simple, but I keep getting the error 000539. It ...
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Calculating change of slope angle within given slope interval using ArcGIS Pro

I need to find areas of rapid slope change greater than 10º within a slope interval of 28º < slope < 55º. I created a slope layer from the DEM and then CON (spatial analysis) to isolate the ...
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''pixelatted'' ''griddy'' result from slope function (QGIS) [duplicate]

I use the SRTM downloader to download my DEM's, then it happens very often that when I create a slopemap there are weird artefacts in the slope map. Something I do before making the slopemap is ...
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5 votes
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Draw buffer around points considering slope in QGIS

I generated random points on a map. Around each point I would like to draw a circular buffer which considers the slope in that area, and within these circular buffers I would monitor tree height in ...
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Calculating area of polygon with consideration of slope in QGIS [duplicate]

I would like to know if there is an easy/efficient way in which you can calculate the area of a polygon considering the irregular slope underneath the polygon. I would like to know a solution in QGIS.
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Raster calculator does not show right result ( only show true)

I am using ArcGIS 10.5. From a DEM, I have created a new raster showing slope using the slope tool. The colour scheme was automatically classified into 9 tiers. What I want to do is query this raster ...
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Raster Calculator in processing scripts crashes using PyQGIS

I am currently writing a processing script for QGIS that goes as follows: Takes in a digital elevation model (DEM) tiff file, a shapefile mask of the study area, and a slope cutoff value in percent ...
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Correct measure unity for slope and aspect in order to work in QGIS with "r.sun.insoltime"

I'm using QGIS 3.10 and I should create a raster that shows the hours of sunlight referring to a given day for my province. r.sun.insoltime (Fig. 1, sorry it's in Italian but I traslate) to work asks ...
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Correct format for slope and aspect in order to work in QGIS with "r.sun.insoltime" [closed]

I'm using QGIS 3.10 and I should create a raster that shows the hours of sunlight referring to a given day for my province. r.sun.insoltime (Fig. 1, sorry it's in Italian but I traslate) to work asks ...
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5 votes
1 answer
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QGIS slope output problems

I've been trying to calculate slope in percentage for a project I'm working on but keep running into this issue Whenever I calculate slope using the designated Slope tool or the r.slope.aspect tool I ...
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Weighting the flow accumulation raster by the slope raster in QGIS

I am trying to represent de equation of Mahoney et al. (2018) https://www.sciencedirect.com/science/article/abs/pii/S0022169418302877 Where Si is the slope in the cell i, ΣSup is is the sum of the ...
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gdal_proximity not working if -maxdist is GEO even if raster is projected

I have a boolean raster layer where 1 are cells with slope higher than 15 degrees, and 0 lower. If I run a gdal_proximity command like gdal_proximity input.tif output.tif -distunits GEO -maxdist 20, ...
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Bad result when extract slope from HGT using GDAL

I'm trying to generate a slope tif from a HGT DEM file from SRTM. I'm following this posts: https://blog.mastermaps.com/2012/06/creating-hillshades-with-gdaldem.html https://blog.mastermaps.com/2012/...
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3 votes
1 answer
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Calculate 3D area with an DEM in QGIS

I have a lot of my projects that are located in mountains. When I draw my polygones, I can easily calculate $area, of course. But in many cases, I underestimate the surface of my polygons due to the ...
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Finding slope of polygon using ArcMap

I am using ArcMap and I am trying to find the slope of a polygon. I have a polygon of Cyprus which consists of all parcels of land. Then I have the DEM for Cyprus from where I can find the slope. From ...
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2 votes
2 answers
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Relation between Solar Radiation and Elevation: Satellite Data

I used DSR (Downward Shortwave Radiation) data from MCD18A1 product and GHI (Global Horizontal Irradiation) data from SOLARGIS to create solar maps: Using this elevation map: I see that the solar ...
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1 vote
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Converting a degree slope raster to a percent slope raster, without a DEM, using raster calculator

I've been given a raster of degree slope which I need to convert to percent slope. As the original DEM is not available and those who provided the raster want me to work with this one, I have to ...
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A way to add Terrain type coefficient (as a raster) in functions of movecost package R?

Im using movecost R package, it allows to add changes in Terrain Type factor as a coefficient (N). I need this to vary between the several terrain types in my study area. So, can N be a raster with a ...
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Plotting polyline trail using slope raster with least change in slope and ArcMap [duplicate]

How do I plot a trail in ArcMap so that it runs from point A to point B? This is part of a larger model I am working on that takes various variables into account and creates a cost layer that I then ...
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3 votes
1 answer
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Highlighting slope in QGIS

I created the slope layer in QGIS through "Raster > Analysis > Slope" and then used the function in GRASS r.slope.aspect, but how do I highlight a slope of 0° degrees to 60° degrees? I ...
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Understanding Analyse > Slope function of QGIS

Playing around with QGIS I discovered the tool 'Analyse > Slope' and I wondered what it actually tells me. Is it an additional information to let's say contourlines, which already provide info on ...
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How does QGIS calculate slope?

There are several ways to calculate slope in qgis using a DEM layer, but how does it actually work? My results show pixels with a slope of 40°+, this seems like a lot (in my DEM, one pixel is 25*25 m)....
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GDAL Slope function not working with SRTM DEM data?

I'm a QGIS rookie trying to generate slope data for research projects in South Africa. I've managed to download DEM data from Bing Aerial maps using the SRTM-downloader but cant get the GDAL slope ...
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Calling help for ArcPy function from within IDE

In IDLE (for Python v2.7.2 within my ESRI path), when I type: help(arcpy.gp.Slope_sa) I get: Help on function <lambda> in module arcpy.geoprocessing._base: <lambda> lambda *args which ...
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Statistical difference in DEM-height compared to a specific point(feature)

Recently I've been struggling when trying to compare surrounding points of a DEM to a specific one (a feature in my case. A castle to be precise). I want to find out how steep a slope in an area ...
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3 votes
1 answer
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Calculating average slope and compass point of polygons in QGIS 3.18

I am using QGIS to rank about 800 PV areas according to their potential. I have a vector (.shp) layer with certain areas in polygons (inc. attribute table, every polygon has it's own ID). Now I would ...
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Calculating slope between two points

I want to know slope value between two point with lat and long coordinates. I can also get DEM values at lat long location for both points. What should I do next in order to calculate slope?
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Error 99999 All raster processes fail in ArcGIS

I'm using ArcMap 10.8.1 and wanted to e.g. do a slope calculation on a Digital Elevation Model. Now I´m getting Error 999999 which usually refers to a bug or some unexpected error. First I thought it´...
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Dynamic Slope Calculation on ArcGIS Online Web Application

I have a DEM raster layer in our own GIS portal. It is then included in a web map online from which a web application is created. I am looking for a way that would allow users to calculate slope by ...
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Changing length of Shortest_Line for CAD-like slope pattern using QGIS

I haven't found a tool/plugin that could do this, but I am almost there. Here is what I want to do: I want to create a slope like the ones from CAD programs, but I don't have and don't need a DEM. It'...
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5 votes
2 answers
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Determining homogenity of flatroofs based on digital surface model / slope layer using QGIS

For the city of Berlin I have a digital elevation model as a 1x1 raster dataset from what I counted the slopes and I have shapefile data containing the outlines of buildings. My goal is to find ...
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r.slope.aspect grass gis datum format on dx and dy analysis

I'm performing terrain analysis due to photovoltaic installation on QGIS with r.slope.aspect plugin. I'm interested in evaluate differently N-S slope and E-W slope based on the PV system I would ...
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Calculate slope/gradient along streams (lines) segments in R

I would like to calculate the slope for stream segments in R. The stream network has been derived from the DEM. I have split the stream segments into equal parts of 100m (or less) and I have the DEM (...
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3 votes
1 answer
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Generating vector slope maps using GDAL

I have a DEM file that I created a slope map of using gdaldem slope. This works fine and if I view and colorize it, I can now see how steep a hill is but now I'd love to create a shapefile out of that....
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1 vote
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Exporting slope values from DEM-derived rasters to CSV from QGIS [closed]

I want to export the slope values with their corresponding latitude and longitude into a CSV file. There's a DEM of a region having an irregular shape (not square). I have to generate the slope rate ...
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1 vote
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Extracting Factors Causally Related to Landslides from DEMs (SRTM) [closed]

I have the SRTM dataset, and I've managed to write some python code to show elevation and slope heatmaps. The code runs fine, and the elevation data is reliable (I checked some points from the web), ...
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2 votes
1 answer
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"Raster map not found" error using GRASS r.walk

I'm using GRASS' r.walk for the first time, and I'm trying calculate the best path between two different points. I have a DEM (from SRTM) and a slope map derived from that same DEM. Both are in the ...
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How to calculate the slope of my polygons using DEM

I downloaded elevation data (DEM) of my study area from NASA and I converted it to slope. How do I calculate the slope of each farm at my study area? I have a shapefile containing the polygons of the ...
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1 vote
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Implementing drainage ditch in QGIS

In QGIS, I am trying to simulate some measures against erosion. One measure would be to install a drainage ditch at a contour line, where the slope goes from e.g. >30% to <30%. What I've tried ...
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Creating SLOPE from .ERS file using ArcMap

Working with ArcGIS Desktop 10.8. I have a .ERS file, it is a georeferenced image and the pixel value is a sea depth value. The depth varies from 0 to -2600 m. I am trying to create a SLOPE (degree) ...
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How to calculate and store (ArcMap) slope on huge mosaic dataset?

I have a huge raster dataset stored in a geoDB (DHM with 2m resolution for all of Switzerland), uncompressed size ~75 GB. I want to use the ArcMap Slope tool (or another tool would also work) to ...
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1 vote
1 answer
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Calculating Slope from DEM in QGIS

I have a world DEM raster in QGIS in EPSG:4326 with elevation units in meters. I'm trying to get a raster of the slope of the terrain, and I'm doing so using the "Slope" tool under "...
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Getting slope from DEM.tif using Spatial Analyst

I have a DEM.tif file and I want to get the slope. I know I use the Slope tool from Spatial Analyst. But, I'm confused which output_measurement to choose from (i.e degrees or percent rise). Basically, ...
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Combine slope info with Landsat for classification in Google Earth Engine

I wanted to add slope data as a band to filtered Landsat data. I used ee.Image.cat to "merge" two images. I can see added band in a merged image, but when I perform the classification (which ...
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