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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6
votes
1answer
2k views

Calculate Topographic wetness index in SAGA

i am currently working on a project which involves the quantification of the wetness in certain areas. However it produces quite different results from what i expected. I'll describe the steps i have ...
1
vote
1answer
411 views

ArcGIS Online Topo Maps

ArcView 10.1 does not have this kind of topo map to "Add Data". Where do I find this type of topo map, preferably free. ArcGIS online does not seem to offer this type of topo, unless I am not seeing ...
9
votes
3answers
885 views

What are common methods for converting raster digital elevation data to vector contours?

In researching this I have found many references to the opposite, creating elevation data from contours, but nothing regarding contour creation. Preferably, I am looking for open source solutions like ...
4
votes
1answer
633 views

USGS Topographic Map Online API

I am creating a website for a non-profit organization and would like to plot points on a map similar to this: http://www.arcgis.com/home/item.html?id=931d892ac7a843d7ba29d085e0433465 I am currently ...
3
votes
4answers
3k views

Add UTM labels to grid in qgis

I try to use qgis to create a custom topographic map for outdoor use: UTM, 1:50000. What these maps usually have is a 1km x 1km grid, which at the bottom is labeled with a shorthand for the ...
4
votes
1answer
837 views

Terraserver replacment - source for US Topo maps?

Now that Terraserver has been shut down (or at least that's how it appears), is there an alternative WMS server for US topo maps? Probably too much to hope to find one that provides vector layers ...
0
votes
1answer
239 views

Plotting Smith and Sandwell global seafloor topography grids

Does anybody have any experience with plotting Smith & Sandwell 2-minute Mercator-projected grids in ArcGIS? I've downloaded one in two formats: ers and img. I've found tools for processing .img ...
5
votes
1answer
379 views

How to restrict or block certain paths in NetworkX graphs?

I am trying to calculate shortest path between 2 points using Dijkstra and A Star algorithms (in a directed NetworkX graph). At the moment it works fine and I can see the calculated path but I would ...
3
votes
1answer
1k views

Map Grid Index / Reference for Canadian Topo Map

Does anyone know where I can find some kml at different resolutions to show the grid reference for the Canadian topographic maps (CanTopo and toporama). Much like is displayed on the map here: ...
8
votes
4answers
2k 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 ...
4
votes
3answers
699 views

Australian Topo Map GeoTIFFs

Does anyone know if Australian topo map GeoTIFFs are made available anywhere (preferably for free)? LINZ makes them available in New Zealand - http://www.linz.govt.nz/topography/topo-maps/index.aspx ...