This dataset is an time-serie of Sentinel-2 Analysis Ready Data (ARD)- derived Anthocyanin Reflectance Index (ARI) computed from Sentinel-2 data. ARI is is a reflectance measurement, sensitive to vegetation pigment content using the forumla ARI = (1/b3) - (1/b5). See Gitelson et al. (2009) DOI: 10.3732/ajb.0800395.

Anthocyanins are pigments common in higher plants, causing their red, blue and purple coloration. They provide valuable information about the physiological status of plants, as they are considered indicators of various types of plant stresses. The reflectance of anthocyanin is highest around 550nm. However, the same wavelengths are reflected by chlorophyll as well. To isolate the anthocyanins, the 700nm spectral band, that reflects only chlorophyll and not anthocyanins, is subtracted.

ARI values for the examined trees in this original article ranged in values from 0 to 0.2.

Values are provided as integer and multiplied by 1000

Metrics: annual (_annual) and seasonal (_spring; _summer; _autumn; _winter) mean (_nanmean), standard dev (_nanstd), min (_nanmin), max (_nanmax), median (_nanmedian), and amplitude (_range)

Data format: GeoTiff