Description: The distribution of rockweed macroalgae was determined through a combination of remote sensing and field work in the Summer – Fall 2024. Preliminary rockweed distribution was calculated in Google Earth Engine with 2015 Leaf-off aerial imagery of New Hampshire (4-band) and National Agriculture Imagery Program (2012 – 2016, 4 – band). Manual thresholds of the non-difference brown algae index, non-difference water index, ratio of Red – Blue bands, and elevation (NAVD88 m) were used to differentiate rockweed from open water, bare mud, salt marsh, and overhanging tree canopy in the intertidal zone. Field inspections of the preliminary classification were conducted by boat along all tidal rivers in the estuary to remove erroneous classification of salt marsh and overhang tree canopy. See McKown et al., 2025 for detailed project description.
Service Item Id: d0f65d7f418541b3bae689608678083e
Copyright Text: James McKown, Coastal Habitat Restoration Team, Jackson Estuarine Laboratory, University of New Hampshire