How did temperature vary from year to year in the study period, 2012 - 2017?
Which years were the hottest… The coldest?

Calculate the GDD0 accumulated over each year at all stations. At station, rank the years from hottest (most GDD0 accumulated = 1), to coldest (least GDD0 accumulated = 6). Create a tally of how many times each rank is assigned to each year, and visualize it.

Histogram for each year…

At each station… which year had highest gdd0? (i.e… accumulated the most heat)

…How about the lowest?