Figure 1. Melt against age (upper panel) and July insolation against age
(lower panel) for the GISP2 site. Years containing melt features are shown by
thin dotted lines. The heavier textured line is the 100-a running mean
of melt frequency (number of melt features per 100 years), and the heavy
black line is the 1000-a running mean. The lower panel shows
deviation of July insolation from
modern values in calories/cm2/day,
from Berger (1978; 1979); positive
values indicate more insolation than today. Data from: Alley, R.B. and S. Anandakrishnan.
Variations in melt-layer frequency in the GISP2 ice core:
implications for Holocene summer temperatures in central Greenland. Annals
of Glaciology 21, 64-70 (1995)
