Crown polygons associated with canopy foliage samples are in a different projection compared to other remote sensing and spatial data from NEON
May 29, 2024
Since NEON started delineating crown polygons during canopy foliage sampling, these polygon shapefiles have been delivered in the WGS1984 projection (e.g., in decimal degrees). On the other hand, all other NEON remote sensing and spatial data are projected on the UTM grid (in meters). For the 2024 sampling season and onward, NEON will project field-delineated crown polygons in the UTM grid before sharing them as part of Plant Foliar Traits.
Regarding existing crown polygons, NEON will update the projections according to the following timeline:
Crown polygons collected in 2023 will be updated by the end of August 2024. These are not yet in a data release and users downloading provisional data will be able to see the changes immediately
Crown polygons collected in 2020-2022 will be updated in the fall of 2024, but since these data are in static data releases the updates will not appear until RELEASE-2025 is available in January 2025
Until the updates are made, note that there is nothing wrong with the polygons, it is simply an issue of mismatched units. When using a Geographic Information System like ArcGIS or similar, the software likely re-projects the polygons when loaded alongside NEON remote sensing or other spatial data. However, if using a programming software such as R, users will need to specify the UTM grid for the polygons to properly align with NEON remote sensing data.
Please use the Contact Us form for further inquiries; please select DP1.10026.001 in the Data Product dropdown list and include the term "Crown polygon projection" in the body of your request.
