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Historical trend analysis of phenology dates across the Western US from 1982 to 2016

December 1, 2021

These data represent key phenology trends across the western United States from 1982-2016. Using two remote sensing datasets, CMGLSP and VIPPHEN-EVI2, trends were calculated for four phenology variables: Start of Season (SOS), Peak Instantaneous Rate of Green-Up Date (PIRGd), Peak of Season (POS), and End of Season (EOS). The Theil-Sen slope and standard deviation were applied to the phenology metrics to evaluate how phenology dates and variation in those dates have changed through time. The Mann-Kendall test was also applied to give an indication of trend significance. Lastly, we include the mean and standard deviation of each metric across the time period.