Archive for the ‘Topography’ Category

Stunning Maps of World Topography [In 3 Lines of R]

Friday, February 7th, 2014

Stunning Maps of World Topography by James Chesire.

From the post:

Robin Edwards, a researcher at UCL CASA, has created these stunning topographic maps using the high resolution elevation data provided by the British Oceanographic Data Centre. The transitions from black (high areas) to blue (low areas) give the maps a slightly ethereal appearance to dramatic effect.

The maps are truly impressive.

BTW, the maps really required “3 lines of R.”

Topological maps or topographic maps?

Friday, December 27th, 2013

Topological maps or topographic maps? by Dave Richeson.

From the post:

While surfing the web the other day I read an article in which the author refers to a “topological map.” I think it is safe to say that he meant to write “topographic map.” This is an error I’ve seen many times before.

A topographic map is a map of a region that shows changes in elevation, usually with contour lines indicating different fixed elevations. This is a map that you would take on a hike.

A topological map is a continuous function between two topological spaces—not the same thing as a topographic map at all!

I thought for sure that there was no cartographic meaning for topological map. It turns out, however, that there is.

A topological map is a map that is only concerned with relative locations of features on the map, not on exact locations. A famous example is the graph that we use to solve the Bridges of Königsberg problem.

A useful reminder.

Although I would use even topological maps of concepts, establishing relative locations, with caution. Concepts have no universal metric and therefore placement on a topological map is largely arbitrary.

OpenTopography Project

Friday, December 14th, 2012

OpenTopograpy: A Portal to High-Resolution Topography Data and Tools

Which ironically has its “spotlight” on:

Discover Lidar Data Hosted by NCALM and USGS from OpenTopography

Which is summarized in the “spotlight” as:

The OpenTopography Find Data page is updated to display not only OpenTopography hosted-data, but also provides linkages to data hosted at the NCALM Data Distribution Center and USGS Center for Lidar Coordination and Knowledge (CLICK). The goal of this collaboration is to make it easier for lidar users to discover and link to online sources of data regardless of host.

Non-self referential and/or paid links that lead to additional content of interest to the reader.

If enough people did that, why we would have a useful WWW.

PS: Introduction to LiDAR video by the Idaho State University Geoscience Department