A fuss over Greenland melting all over has erupted in recent days. Yesterday I had an idea looked, decided to say nothing. More fuss, so here it is.
I grabbed one of the Greenland ice core datasets, GISP2 in this case.
What I am doing is novel off the wall. Data GISP2 Visual Stratigraphy.
This gives a crude visual goodness on the presence of summer, “indication of summer observed”. My thinking here is a summer surface melt will either make a layer highly visible or mushed into invisible. Don’t care which.
A number 0 1 2.5 3 is not very useful, or is it? Wack it through a low pass since this is a valid form of modulation.
The data gets worse as we go back in time, no surprise.
Low pass at 50 years, some ringing, doesn’t matter.
Take the spectra 700AD onwards. (avoid the big zero)
This tends to support a regular something, ballpark of “I have quoted the longest-term average frequency of ~150 years (exactly 153 from the paper) over the past 10,000. Since this is an ice core record that frequency is for the location of Summit only. The frequency ranges from ~80 to 250 years over different sections of the GISP2 ice core”