Arctic tundra functional types by classification of single-date and AVHRR bi-weekly NDVI composite datasets

Maps of functional vegetation types are often used to extrapolate in situ m easurements of biogeochemical fluxes to make regional-scale or biomescale e stimates. The objective of this study was to determine the optimal spectral -radiometric and temporal features derived from single-date and seasonal ti me series NOAA AVHRR imagery for classifying three Arctic tundra functional types. A single-date, three-band (VIS, NIR and NDVI) input yielded a map w ith the highest agreement (86.1% for supervised and 87.8% for unsupervised approaches) compared to a reference map. The map generated with the convent ional maximum value NDVI for 10 semi-monthly periods through the growing se ason was in 82.7% agreement.