Pollution levels in the early 1900s also represented a 10-fold increase from preindustrial levels.Continuous, monthly and annually averaged pollution records taken from the Greenland ice core dating from 1772-2003 produced the results.Gallo was right when he mentioned that compression would destroy the "rings." I believe some dating of ice cores is done via a O16/O14 ratio, but I am not sure.That ratio may be good only to indicate the climate at the time of snowfall.At any rate, the main challenge I am aware of to standard ice core dating has to do with the fact that we really don't know if layers before known time were caused by many different storms in a few years or one season layering a year.We know what we see now, and many extrapolate backwards from that.
Detailed measurements from a Greenland ice core showed pollutants from burning coal--the toxic heavy metals cadmium, thallium and lead--were much higher than expected.
The Arctic amplification phenomenon refers to the faster rate of warming in the Arctic compared to places farther south.
Arctic amplification has been linked to a spike in the number of persistent ...
"But it turns out pollution in southern Greenland was higher 100 years ago when North American and European economies ran on coal, before the advent of cleaner, more efficient coal burning technologies and the switch to oil and gas-based economies," Mc Connell said.
In fact, the research showed pollutants were two to five times higher at the beginning of the previous century than today.