The study and mapping of land surfaces, including relief (relative positions and elevations) and the position of natural and constructed features.

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9
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5answers
3k views

How to aquire a topographical map of Britain?

First of all, let me say that I know next to nothing about GISs. I'm trying to find / make / aquire a topographical map of britain. I want to use it as a height map in Dwarf Fortress so it needs to ...
2
votes
0answers
40 views

3D topographic progress compensation by the least squares method

I'm looking for an explanation of the least squares method used in the case of a correction of 3D point network. We have reference points with known coordinates XYZ. We calculate intermediate points ...
1
vote
1answer
103 views

How to combine depth and topography .asc file?

I have a .asc file produced from a hydraulic model. The .asc file contains depth data of flood inundation. I want to superpose the depth asc file with my topography .asc file so I can identify where ...
1
vote
0answers
321 views

Finding Color Palettes?

Anybody can help me to find the three color palettes of the following map?
3
votes
1answer
221 views

Correcting for local topography in calculating TRI from DEM in ArcGIS

I'm currently investigating the use of different equipment in calculating TRI from elevation data using ArcGIS. From the methods available (http://gis4geomorphology.com/roughness-topographic-position/)...
1
vote
1answer
161 views

How to display steep slopes with the use of Contours?

I am using Arc Map 10.1. I have downloaded contour data as a shapefile. Is there any way to use the contours to display steep slopes so 15%-25% or 25% and greater.
1
vote
0answers
105 views

How can I enhance a topo map I am making as a Christmas gift? [closed]

I am using ArcGIS for Desktop 10.2. I am making a topo map for my girlfriend's brother as a Christmas gift. He is one who will appreciate a good map that was "drawn" in 1958. I know you can ...
2
votes
1answer
1k views

European Mountains Shapefile Data Sources

I am trying to locate a GIS freely downloadable shapefile (preferably polygon) of European main mountain chains (not an elevation data), eg Alps, Carpathian Mountains. I tried variuos sources , ...
2
votes
0answers
62 views

Creating QGIS multi-layer Topo Map of Lorraine Region of France?

I have a project I'm working on where I need a QGIS multi-layer Topo Map go the Lorraine Region of France between Metz and Nancy as a starting point, but I don't know where to start. What I need is a ...
3
votes
1answer
798 views

What is Google's source for topographic data?

I'm looking for as detailed as possible topographic data for a certain area and have found information displayed by Google Maps to be far more detailed than what is provided by 7.5 minute maps (from ...
4
votes
2answers
185 views

Software for amateur topographic surveys

I'm interested in doing rough topographic surveys using my tripod-mounted Brunton transit compass for azimuth readings and laser rangefinder (and maybe an optical level), so obviously going to be much ...
1
vote
1answer
167 views

Learning about bathymetry?

Besides reading about bathymetry, I would like to work on some hands-on training that I can learn about bathymetry. Is there any good bathymetry out there that I can get some training with the ...
2
votes
1answer
1k views

Detailed topographical map of Istanbul

I need to acquire a very detailed topographic map of Istanbul, Turkey without any markers. Do you know such sources who provides these kind of maps? I tried to Google it, but the results were far ...
1
vote
2answers
394 views

Mercator vs. Web Mercator for Large Scale Topographic Maps

I have 8 terabytes of imagery that is in either lon/lat or UTM projection that I will be using for the basis of large scale topographic maps. I have been studying the differences between Mercator and ...
2
votes
1answer
108 views

How can I properly clip a shape file to get the section I want using QGIS?

I've tried the other "how to clip" instructions here, but consistently get an empty shapefile from the clip. QGIS Version: 2.4.0-Chugiak OS: MacOS 10.10 Input File: San Diego (South Map) 1999 Topo (...
3
votes
1answer
65 views

Looking for detailed relief tiles

A few days ago I stumbled over a map which had beautifully rendered, detailed topographic tiles of the whole world. It was similar to google-physical with a strong contrast (shadow/light) and contour-...
2
votes
0answers
798 views

Find Average Elevation - ArcGIS Desktop

I am working with 2 shapefiles. One contains the boundaries of a city, the other contains polylines representing the topographic features of the area. Essentially, the polylines make a topographic map....
0
votes
1answer
156 views

How to insert “Topo North Arrow” using ArcObject

Does anyone know how to insert "Topo NorthArrow" using ArcObject C# SDK? There is no example or snippet. I am not sure if it is even available through SDK. Thanks in advance.
3
votes
1answer
4k views

Plotting elevation maps and shaded relief images from latitude, longitude, and elevation pairs

I have a set of latitude, longitude, and elevation pairs (roughly a grid of such values, though it is not uniform), and I'd like to be able to plot an elevation map and perhaps also a shaded relief ...
1
vote
1answer
110 views

Why do different USGS Topo maps show different elevations for the same control point?

So I have been investigating the area around Jerome and Clarkdale Arizona using different USGS Topographic map sources of the same scale, but different time periods, and find that in some cases, the ...
3
votes
0answers
117 views

Where do I find official summit elevations found on USGS topo maps?

I'm creating topo maps for my day hikes guides for national parks. I've already done one for Glacier National Park. When I was working on summits, I downloaded the data for Montana from GNIS and when ...
4
votes
1answer
822 views

Topographic Index - Why is upslope contributing area divided by downslope contour width and not upslope contour width?

In the Topographic Index calculation, a is the upslope contributing area per unit contour length. Is the "unit contour length" calculated from examining the contour widths of the downslope cells that ...
2
votes
1answer
172 views

How to disassociate roughness from slope

How to measure topographic roughness irrespective of slope in ArcGIS? I have used many methods to generate roughness layers, including TRI, VRM (which is supposed to be less correlated with slope), ...
5
votes
2answers
216 views

Why are poles missing from GIS topographic data?

Why are poles data missing from most topographic resources ? Data from 60⁰ to 90⁰ lat frequently missing from topographic GIS data. Example with SRTM4.1: Common sense or deduction lead me to think ...
2
votes
0answers
279 views

How to develop an elevation profile tool with high precision? [closed]

Similar to the Google Earth elevation profile tool, also similar to this: http://www.geocontext.org/publ/2010/04/profiler/en/?send_comment=success#comments I want to be able to use my own set of ...
3
votes
3answers
104 views

Ontario Topographic and Property Data

Looking for Ontario topographic data and property line data; willing to purchase the latter. Shapefiles or file geodatabase files would be optimal. In terms of topographic data, I am looking for: ...
2
votes
2answers
929 views

GDAL Conversion of US Topo GeoPDFs

I've used GDAL_translate with "--config GDAL_PDF_LAYERS" option to convert US Topo GeoPDFs to GeoTIFF and it works great for creating collarless topos based on the new format. However, I can't get it ...
3
votes
1answer
208 views

data source for worldwide cross-sections of topographic and bathymetric for woodworking art project?

i am a decent r programmer and statistician, i am able to work with data sets pretty well. i am less familiar with GIS tools, but if given a shapefile i can certainly plot political borders and ...
4
votes
1answer
604 views

How to create a buffer on a linestring with varying or increasing/decreasing width

I want to buffer rivers/streams for a topographic map. I'm using a PostgreSQL/PostGIS database. Usually, I create buffer with ST_Buffer with a constant width. For example, the width of a river buffer ...
1
vote
1answer
170 views

Is there a public CanTopo Web Map Tile Service (WMS / WMTS) available?

Does anyone know of a public CanTopo WMS / WMTS available anywhere? I'm assuming CanTopo is more modern / up-to-date than Toporama? Alternatively, what would be your suggestions for the most pain ...
1
vote
1answer
163 views

Overlap between Google Earth and Topographic OSM

First, I have Google Earth and Garmin BaseCamp with OSM maps. I would be satisfied if the solution is only available on one of these software. A third software that combine both view can be ...
2
votes
2answers
194 views

What USGS maps exist in the 7.5' × 15' metric 1:25,000 series?

While browsing through the library, I discovered that USGS has, in fact, produced some metric maps at 1:25,000. One example is Thendara (NY), 43075-F1-TM-025. As far as I can tell, those maps are ...
2
votes
0answers
17 views

Are there any NTS index maps showing the most recent update?

For the Canadian National Topographic System, are there any index maps available that do not only show map numbers throughout the country, but also the most recently available update for each map? As ...
1
vote
0answers
281 views

What steps does SAGA GIS take when calculating Topographic Wetness, specifically when handling depression filled (by ArcMap) DEM

I am a grad student involved with hydrological modeling. In the model I work on, we are calculating the Topographic Index (TI; without transmissivity - or set to 1) using Quinn's MFD algorithm. We do ...
2
votes
1answer
6k views

Can Compound Topographic Index (CTI) / Topographic Wetness Index (TWI) produce negative values?

I am calculating Topographic Wetness Index for a study area using SRTM DEM (90 and 30m). I've seen several versions of TWI (CTI). I have been using: TWI = ln(As +1 / tanB) where As = ...
2
votes
1answer
81 views

Tiling ArcGIS Desktop Historic Maps

I'm using ArcGIS 10.2 Desktop on a Windows platform. I have georeferenced about a dozen USGS topographic raster maps from around 1900. Each georeferenced map is an now an .mxd file. To the best ...
1
vote
3answers
1k views

Topography: How to get the x,y,z coordinates of highest or lowest point/pixel of a raster GIS?

Given a .tiff topographic raster image with mountains and deep sea, I am looking for the x,y,z specifics of the highest or lowest point. The x,y,z values being: altitude (z-coordinate) latitude (y-...
3
votes
1answer
963 views

Mapping points from total station data in Angle, Horizontal Distance, Vertical Distance

I am working on creating a contour map from total station topo points in ArcGIS 10. The points were collected using H angle, HD, VD instead of XYZ points. I need to create points from these ...
3
votes
0answers
161 views

How to compute surface of raster or any point using ARCGIS?

I have a raster image whose values are a digital elevation model of terrain. I need to know the surface type (topographic characterization) of particular points along transects of this DEM. How to ...
2
votes
0answers
667 views

Why does Topo to raster tool stall in ArcMap 10.1?

I'm having the following problem - An 8 mile by 4 mile set of 2 foot contours. Whenever I start the topo to raster tool, I get a constant loop of the tool running. And running, and running, and ...
1
vote
2answers
574 views

Where can I programmatically download SRTM_V4.1 data?

SRTM v4 is an effort by the folks at CIAT-CSI to scrub, polish, and remove gaps in the raw SRTM data released by NASA (SRTM 3). One userfriendly interface : http://dwtkns.com/srtm/ provides *...
1
vote
1answer
57 views

Rough edges on tiles in QGIS

I'm loading four .ASC files into QGIS, each containing topographical data about a tile of 10 x 10 km. On the map, this data is displayed as black/white and different shades of gray. My problem is that ...
0
votes
1answer
46 views

file type needed to add layer containing contour lines

What file format is usable/recognized by qgis to add contour lines to a map? I'm working with Linux Mint 15, and qgis 1.7.5
9
votes
3answers
361 views

What does this style of line on Topographic maps indicate

If I was reading the purpose of this stackexchange site right, I could also ask general map questions. Not necessarily regarding software. Anyways, I was wondering if someone could inform me what ...
2
votes
1answer
2k views

Polygonize.py outputs into a single file or simple merge?

Given an unique raster topographic file at start, I want to get vector polygons for elevations thresholds 1m, 200m, 500m, 1000m, 2000m into a single shp file. I first slice my raster into 5 (or more) ...
2
votes
1answer
514 views

Gdal_polygonize: How to filter pixels above a given value (elevation)?

Given a topographic GIS raster of one country: Given an elevation threshold n = 50 (meters) How to polygonize pixels when z >= n ? gdal_polygonize.py is not clear on this point. It states This ...
0
votes
1answer
2k views

How to conditionnally assign a new value to pixels of a raster image?

Given a topographic GIS raster of one country crop.tif: Given a know pixel value such as elevation (z) is +73 : $ gdallocationinfo crop.tif 1 1 -valonly > 73 Given an elevation threshold n = 50 ...
1
vote
2answers
634 views

Gdal: How iterate through all pixels of a raster image?

Given a topographic raster image. How to iterate through all pixels of this raster image ? Solution preferably with gdal, in console. Some other libraries/script could be installed. Related: ...
1
vote
1answer
862 views

Gdal: How to get a pixel's value from raster image?

Given a topographic raster image. Given a pixel's coordinate in pixel/lines or geocoordinate. How to get it's pixel value ?
2
votes
0answers
887 views

Topography: How to convert raster into vector layers?

(nb:This project is part of the #Wikipedia #wikimaps project) 1. Question: How to create vector topographic maps from raster image ? How to convert raster topographic image into closed vector ...