Figure 4
From: Canadian Arctic sea ice reconstructed from bromine in the Greenland NEEM ice core
Calibration of the NEEM Br enrichment (Brenr) signal to current and past sea ice extent in the NEEM aerosol entrainment area (Canadian Archipelago, Hudson Bay, Baffin Bay).
Three climate scenarios are evaluated, full glacial (Brenr = 2.5, 20.6–30.7 ky b2k), late Holocene (Brenr = 10.6, 0.03–3.03 ky b2k) and early Holocene (Brenr = 15.6, 9.0–11.5 ky b2k). For each scenario, we employ the maxima and minima of sea ice extent observed between 1979 and 2013 and range of first-year sea ice variability, for calibration. Bromine enrichment is plotted on a logarithmic scale to provide the best linear fit of Arctic temperature variability represented by the NGRIP δ18O profile. 1σ error bars represent the variability observed for the three climate intervals evaluated.
