LANDFIRE Seamlines Explained


Two maps showing seam lines

Some lines may drive you crazy, but there is an explanation ...

If you’ve spent much time working with maps, whether you work with 1:24,000 paper quads or digital data in a GIS, you have probably encountered items that just don’t make sense. A cartographic enthusiast (nerd?) would call these “mapping artifacts.” One particularly irksome artifact, common in maps created from satellite imagery, including LF products, is abrupt linear changes or "lines" often referred to as "seam lines."

The hard boundary these lines create in ecological data, like vegetation cover type, are a real burr under the saddle of both the mapper and the map user. In this brief article Kori Blankenship of the TNC-LANDFIRE team explores and explains some common sources of lines in LF products and how LF scientists work to minimize them.