One of the lessons drawn from comparing Greenland to Antarctica and many other
places is that some of the temperature changes (the ice - age cycling) are very widespread and shared among most records, but other of the temperature changes (sometimes called millennial, or abrupt, or Younger - Dryas - type) are antiphased between Greenland and the south, and still other temperature changes may be unrelated between different
places (one
anomalously cold year in Greenland does not tell you the temperature anomaly in Australia or Peru).