Questions tagged [terrain]
The vertical and horizontal dimension of land surface
238
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Making world map with terrain colours in QGIS
In QGIS I would like to create a world map that has terrain colours (e.g., deserts or vegetation), as in the attached map (Gehring et al. 2022), particularly for the African continent.
How should I ...
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Some iterative way to compute heading and GPS projection at the same time?
I have the following situation:
An off-road machine has a GPS antenna that is not at the center of the rear axle (this point is my path-tracking-control point). Let's say it's 3 meters from the rear ...
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Converting GeoTIFF Elevation Data to 3D ZXY Tiles
I have a GeoTIFF file which includes elevation data. I visualized the TIFF by pyplot:
from osgeo import gdal
import matplotlib.pyplot as plt
import numpy as np
from mpl_toolkits.mplot3d import Axes3D
#...
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Creating 3D surface / terrain in ArcGIS Pro WITHOUT 3D extensions?
I understand GIS principles, but I am a new user to ArcGIS Pro.
I am currently looking to create a terrain type model / surface in 3D, using a georeferenced .ASC file containing ground heights.
Is ...
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Creating topographic "layer cake" map a.k.a. Tanaka contour in QGIS
I'm wondering if there is any way to create a map similar to the image below. Basically, it would be the contours extruded, add a singleband pseudocolor ramp as the color on top, and be able to ...
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How to perform terrain correction in Google Earth Engine
How can I perform the terrain correction as the shadows from the mountains severely affect the land use classification results. The random forest model picks the shadows as the water bodies.
Here is ...
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Why doesn't a 1-pixel buffer around the edges of Mapbox's Terrain-RGB tiles show up?
I am reading the documentation of Mapbox's Terrain-RGB tiles. It says:
Buffered tiles. Each map tile includes a 1-pixel buffer around the
edges to enable tile interpolation in uses cases like terrain ...
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XYZ points for terrain models in different resolutions from a PostGIS server
I have a grid of points in a PostGIS DB. This grid is in the resolution 1m and its around 100.000 Points large. Getting these points from the db works for me.
For example like this:
SELECT *
FROM ...
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Units of slope output
I am calculating the slope from the DGM file which is of 1m spatial resolution.
The default CRS is ETRS89 33N 25833 for that particular piece of land in Germany, kustriner vorland.
In what units are ...
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Google Earth Engine - slope
I am trying to use the pre-built function of GEE for calculating the slope of the terrain, but I cannot really understand how the function works, since the documentation is also not really helpful.
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Creating a heightmap from hillshade/radar data?
So there are several threads explaining how to create a hillshade map from DEM. Does anyone know of a method to do the opposite? Essentially all I have is unidirectional radar data which functions ...
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Service area depending on slope in QGIS
I am trying to create isochrons of walking depending on slope in QGIS. I am using the Service Area function and I have a slope assigned for each road. But I don't know how to determine the direction ...
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Most detailed surface map that can be produced from LiDAR data in ArcMap
I want to find old military trenches or at least to get an idea where they were, so that I can go to those areas and survey them.
I know the basic method of conversion from .lasd to elevation raster ...
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Polygons from a raster within an elevation range
In the image below I have generated some isolines starting from the terrain model and I have filtered them within a certain elevation range 800 - 1500m of elevation in QGIS.
But I would like to make ...
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Import a Map from gokml.net to QGIS
I want to import this map into QGIS:
http://gokml.net/maps#ll=48.093157,12.355834&z=6&t=t&s=14
It's the only way I found to display the Google Terrain Map without streets and labels.
If ...
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Convert a raster to show count of cells of a given relationship to each cell
Is there a tool (QGIS preferably), that will look at every raster cell, and compare it to neighbouring (1km) cells and populate the value with a value based on relationship.
Example (and indeed the ...
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Correspondence of 0m elevation height of a digital elevation model (Copernicus DEM) to mean sea level
I want to model future coastal flooding caused by sea-level rise under the latest IPCC scenarios at global scale. To this end, I use the Copernicus Digital Elevation Model (Copernicus DEM: https://...
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QGIS: Average of digital terrain model for a certain polygon
In one layer I have a lot of different polygons, which represent different areas. In addition I have downloaded a digital terrain model, which shows different slope percentages. All of this works, but ...
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What is the difference between TIN vs MESH vs TERRAIN in the context of GIS?
I couldn't seem to fully understand the differences between TIN, MESH, and TERRAIN dataset formats in GIS.
Per Wikipedia
a triangulated irregular network (TIN)1 is a representation of a
continuous ...
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How to determine the area size of a terrain for which I want to calculate its roughness
I want to calculate the wind speed on the ground for a specific location. In order to do so I will use the log wind profile. One of the input variables of this formula is the surface/terrain roughness....
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Terrain creation error using a GeoTIFF file with HEC-RAS 6.2 - "object reference not set to instance of object"
I am attempting to import a TIFF file created in QGIS, into HEC-RAS. I have a projection file as the SRS definition for HEC-RAS, which is derived from a shapefile that lines up with the spatial extent ...
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Band used for deformation estimation using In-SAR
Which polarization of SAR data (C-band - Sentinel-1A) shall I use to get a better deformation map of a mountain terrain - VV or HH?
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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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Error calculating aspect from DEM in R using raster/terra
I have a DEM file gathered using R. The raster and terra packages both have a function to calculate aspect, called terrain(). When using the terrain() function and the units="degrees" ...
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Converting aspect/direction raster from geographic degrees to arithmetic radians
I have a raster/grid representing e.g. terrain aspect or flow direction, coded in geographic degrees (0-360°, clockwise from the north). I would like to convert it in arithmetic radians (0-2π, ...
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Creating TIFF from Contour Lines
I need to quickly create a TIFF terrain (shades of grey terrain) from contour lines, or rather to create a GeoTIFF. In the past, I extracted vertexes from the contour lines and used that to create new ...
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Generate GLTF/OBJ models from quantized mesh (terrain) in CesiumJS?
I’m exploring ways to generate gltf / obj models from terrain mesh. My goal is to show 3d cut-fill volume calculation, something like the following -
I realized that I don’t need to DEM to generate ...
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How to query height of a given lat long coordinate from server side?
I need to some calculation with terrain surface, I use cesium but it works slow.
Cesium has a method sampleTerrainMostDetailed, it gives me height of given coordinates but it calculates height on ...
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Creating Contour Lines in QGIS 3.16 with a distance of 0,10 m
I would like to create Isohypses (Shape) ("Create contour lines") with a distance of 0,10m in a Digital Terrain Model (Shape File).
While processing the command, there are some errors poping ...
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Plan curvature in QGIS
I am trying to obtain plan curvature from a DEM. So far I have tried two methods from SAGA and GrassGIS plugins, however both do not seem to work and give errors.
Do you have a workaround suggestion?
...
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Using Watershed Basin from SAGA in QGIS
I have a weird phenomenon going on in QGIS.
I want to derive a channel network and also the catchment areas using "watershed basin" from SAGA. In the end I want to have the flow direction ...
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How to interpret Terrain Ruggedness Index according to Wilson et al. (2007)?
Is there a categorical scale used to interpret values from the Terrain Ruggedness Index as calculated by Wilson et al. (2007), which is used in the raster library in R?
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Interpreting Ruggedness Index calculated from SRTM Tiles
I am looking for help interpreting the values from Ruggedness Index calculations.
I downloaded SRTM tiles using the SRTM Downloader plugin in QGIS. Then I calculated ruggedness from SRTM tiles in QGIS ...
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Intersection of an arbitrarily oriented 3D plane with a terrain DEM
In a nutshell
I'd like to compute the intersection of a 3D plane (defined by 3 points) and a terrain (given as a raster DEM GeoTIFF), and more particularly the part between two lines of that plane.
...
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Calculating direct solar radiation using QGIS and GRASS
I am using QGIS 3.16.8 and GRASS 7.8.5.
I would like to compare two places in my study area climatically. Since both are only a few 100 metres away, I assume that they only differed in terms of slope ...
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Reproducing terrain ruggedness index from the original paper example [closed]
I am not able to reproduce the terrain ruggedness index for the example used in the original Riley et. al paper.
The example is as follows:
When I try to reproduce the numbers in MS Excel I get ...
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How to calculate the terrain profile in Profile Tools plugin
Now, I'm trying to calculate terrain slope(°) using pyqgis using below process.
Along the specific lines which I want to know the terrain profile, I generated the points using 'qgis:pointsalonglines'....
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An error occurred when using the terrain function in the production of Shiny dashboard
I am new to the 'shiny' package. I just try to produce an aspect map from the existing DEM data using the Shiny dashboard for training purposes. However, I faced the below warning in R and error in ...
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Grid from SAGA natural neighbor results in black grid
I'm new in QGIS and I'm following tutorials mainly on YouTube so I created a path in Google Earth then exported to kml which is converted to txt via GPS visualizer.
When added delimited layer it shows ...
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Why do I get negative values for the topographic position index (TPI)?
I run into issues, when trying to calculate the topographic position index (TPI).
I get values ranging from -13 to 17. And the resulting layer looks a bit odd, too:
If I understand it correctly, this ...
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Free or FOSS Elevation API for Heightmaps (image files) instead of elevation points
I'm coming from a Blender background, in which simple FOSS extensions exist (like BlenderGIS) that download SRTM/Aster Elevation Data and make a terrain based on this. I'd like to make something ...
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How to get elevation raster data at custom scales for a specific region?
I'm new to GIS and trying to obtain elevation data for a specific region, transformed to raster data with a custom cell size of 10 meters.
My first attempt was to download a TBDEM dataset from USGS ...
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How do I overlay vector data over a 3D terrain basemap?
I would like to create a map that is similar to the one found here: https://www.reddit.com/r/MapPorn/comments/lpo557/geological_map_of_north_america/ .
I'm thinking that you could replicate this with ...
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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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Terrain Ruggedness Index (TRI) calculated in QGIS is approx 4 times that calculated in GDAL
When I calculate TRI using QGIS and GDAL tools for the same elevation DEM, I get results that are comparable between the two except that the absolute values in QGIS are approximately 4x that in GDAL. ...
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Selecting Terrain Dataset by elevation in ArcGIS Pro
I have added the Terrain Dataset to my project in ArcGIS Pro. I would like to select the areas which have an elevation above some threshold.
Eventually, I want to use this selection as a clipping mask ...
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NA values as result from Grass functions (r.slope.aspect, r.sim.water) in R
As the result from r.slope.aspect I get a raster with only NA values. r.param.scale works, but doesnt generate dx and dy maps, which I both need for r.sim.water function.
Code snippet 1 (initialize ...
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Using Aspect tool in QGIS
For my bachelor thesis in biology I´m working with QGIS 3.14 (Pi) and tried to create a layer where the slope aspect/expositon/exposure is presented. I´ve got a DTM1 on hands. There is this function ...
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Terrain aspect similarity
I have a point data set with terrain aspect at the location of the points, measured in degrees. I want to compute the similarity of aspect between the points, e.g. 70° is similar to 90°. This is ...
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Lidar Dataset for Toe and Crest Detection
I have read a paper on Terrain Toe and Crest Feature Detection and Labelling forAutonomous Mining and started working on building the code for this. But I am unable to find the dataset used in the ...
