The USGS has collected some amazingly useful digital images. The problem is that some of the data is accessed via FTP sites or Web sites that are little more than alphabetical lists. Others are found in graphical web mapping interfaces that are perhaps the best proof of why the move to Web-based software is detrimental to usability and our society’s technical capabilities.

A further problem is that our tax dollars have already paid for the collection of this data, yet the USGS seems intent on making most of it available only for fees to be determined by the private companies that have access to the best data.

For this project, I need a color aerial photo of the Bayfront Park, and terrain data for the 4 kilometers surrounding the park (for RF propagation).

Confusingly, the USGS has numerous methods for downloading this data, including The National Map, the National Atlas, the EarthExplorer, and the Seamless Data Distribution System, with no clear indication of which system is the best for any particular purpose or data type. And with all of them, there is very little information about what each type of data offers; at least not presented in a way that is quick and easy to digest.

What is extremely troubling is that the USGS is about to delete vast amounts of data from its online database—the entire Digital Elevation Models (DEM) and Digital Line Graphs (DLG) data sets. While these are ostentiably being replaced by newer, better data, the removal of historical data is always troubling, not all current software can handle the new SDTS data format, and there is some question as to whether the newer data—specifically, the NED data set—is as good as the older data.

In the following posts, I’ll comment on how easy it is to download data in useful data formats from these sites.