November, 2011


GIS Data

False Color/Near Infrared Landsat Imagery 1975-2005False Color/Near Infrared Landsat Imagery 1975-2005

Landsat Satellite Imagery

450 terrabytes of Landsat imagery from the European Space Agency’s archives has been opened up to the public for free.  The agency’s archives covers 30 years of Landsat data.  Data that can be requested for free from ESA’s archives includes: Archived Landsat-4 Thematic Mapper (TM) data in December 1982 Archived […]

GIS Learning

What is the Public Land Survey and Why Do We Still Use It?

What is the Public Land Survey and Why Do We Still Use It?

Have you ever wondered why on legal documents your house is not listed with your address but rather by parcel location?  If you have ever seen something akin to the southwest corner of the northeast corner of the northwest corner of Section 21, Township 4, that coordinate system is the […]

GIS Learning

Updates on Mark Bosworth ( #findmarkbosworth ) and Atanas Entchev ( #freeatanas )

Updates on Mark Bosworth ( #findmarkbosworth ) and Atanas Entchev ( #freeatanas )

Ongoing efforts to help two geospatial professionals haven’t netted positive results.  Still, there are actions that every GIS colleague can extend to help. Mark Bosworth, an Oregonian who may have brain cancer that has affected his cognitive abilities, has been missing since September 16 when he disappeared while volunteering with […]

GIS Software

Creating Maps for Wikipedia and Printed Materials with ShareMap.org

Creating Maps for Wikipedia and Printed Materials with ShareMap.org

The availability of simple online mapping tools (such as what Google Maps offers) allows those with limited geospatial technical knowlege to design simple maps via  a web browser without using any external professional tools. These tools open up mapping to anybody who wanted to create a map of their neighborhood, […]

GIS Software

TdhGIS – Free Software for Vector Based Analysis

TdhGIS – Free Software for Vector Based Analysis

TdhGIS is a free GIS software application for Linux and Windows operating systems for spatial analysis of vector based geographic data.  The software can also be used as a shapefile viewer and editor.  Tim Hirrel is the developer of TdhGIS which was developed using C++, wxWidgets and SQLite.  Hirrel, water resources […]