Tag: USGS
USGS Map Services for The National Map
There are several map services that USGS supports. These allow you to view nationwide data from The National Map in your GIS software. To use these in ArcGIS – select Add Data button then choose GIS Server from the list, then “add ArcGIS Server” To add the tiled map cache (these are background topographic map images, including [...]
Timelapse Satellite Imagery – View Changes on Earth over Time
The series of Landsat satellites has been collecting global imagery continuously since 1972. A total of eight satellites and millions of pictures (and trillions of pixels) has resulted in a hugh amount of imagery which, when compiled, visualizes the massive amount of global change over the past thirty+ years. Landsat satellites capture imagery of the [...]
SDTS – GIS Data Standard
SDTS stands for Spatial Data Transfer Standard. SDTS was a standard for transferring earth-referenced spatial data across disparate computer programs. The U.S. Geological Survey (USGS) released SDTS after twelve years of development and testing in 1992 and was subsequently approved as Federal Information Processing Standard (FIPS) Publication 173, known as FIPSPUB 173-1, 1994. The FIPS version has been superceded [...]
Free GIS Books
Building a collection of reference and academic texts on GIS can be costly. There are some free online source materials that can be a valuable contribution, especially if your book budget is nonexistent. Most of these free GIS books are available in downloadable PDF format and can be read from a computer or on an [...]
Mapping Access to Safe Water
World Water Day is held on March 22 each year as a way to bring global attention to the world’s freshwater resources. Started by the United Nations, the theme for this year’s World Water Day is Water and Food Security. Access to clean water is not just necessary for hydration, but is needed to produce [...]
