Figure 3.

Holocene climate forcing. (a) Reconstructed Greenland temperature. (b) Reconstructed and modeled Greenland temperatures over the Holocene from various climate model experiments. Experiments without volcanic and solar forcing that exhibit long-term trends similar to that of full forcing are not shown for the sake of simplicity. (c) Modeled NH average temperatures with full forcing (blue) and without volcanic forcing (green) both relative to the average of the past 1000 years from the full forcing run. (d) Modeled high (60–90°N), middle (30–60°N), and low (0–30°N) latitude average temperatures. (e) Annual insolation at 72°N (orange)⁶³ and solar activity (red)³¹, GHG (blue; include CO₂, CH₄, and N₂O, Methods) and volcanic forcing as raw (black) and 101-year RMs (green) (Methods). Note that the raw volcanic forcing has a different scale. Values are relative to averages of the past 1,000 years. Model outputs are from individual runs and smoothed by 21-year RMs. Blue shades are the Greenland cold episodes as in Fig. 2.