Fig. 2: Proxy records for the Arctic sea ice and pan-Arctic river environment during the Holocene.

a Global sea level³⁶ and solar insolation in late summer at 75° N⁵¹. b–d Solar insolation in early summer at 75°N⁵¹ and reconstructions of sea ice change in the East Siberian Sea (this study), the Laptev Sea¹⁸, and the Chukchi Sea¹⁰. The smooth lines represent the binomial expression of the data to obtain the Holocene orbital tendency. Reconstructions of Russian pan-Arctic river heat discharge in e the East Siberian Sea (this study) and f the Laptev Sea^49,63. g Pollen-based reconstructions for the Russian Arctic temperature and precipitation in the summer season from the Dolgeo (solid black line)²² and CH-12 (dotted black line) stations²⁰. h Reconstruction of Siberian permafrost thawing^45,46. i Summaries of air temperature in mid- and high-latitude regions²¹ and the westerly dominated central (solid purple line) and summer monsoon dominated eastern Asian (dotted purple line) moisture in summer¹⁹ based on hundreds of sedimentary records. The green band represents the mid-Holocene during 7.5–4.0 ka. Sed. Rate, MAR, and brGDGTs indicate the sedimentation rate, mass accumulation rate, and branched glycerol dialkyl glycerol tetraethers, respectively. See the reconstruction for the past 9000 years in Supplementary Fig. 9.