Rapid sea-level rise caused by the collapse of large ice sheets is a threat to human societies. In the last deglacial period, the rate of global sea-level rise peaked at more than 4 cm yr⁻¹ during Meltwater Pulse 1A, which coincided with the Bølling warming event some 14,650 years ago. However, the sources of the meltwater have proven elusive, and the contribution from Eurasian ice sheets has been considered negligible. Here, we present a regional carbon-14 calibration curve for the Norwegian Sea and recalibrate marine ¹⁴C dates linked to the Eurasian Ice Sheet retreat. We find that marine-based sectors of the Eurasian Ice Sheet collapsed at the Bølling transition and lost an ice volume of 4.5–7.9 m sea-level equivalents (SLE) over 500 years. During peak melting, 3.3–6.7 m SLE of ice was lost, potentially explaining up to half of Meltwater Pulse 1A. A mean meltwater flux of 0.2 Sv over 300 years was injected into the Norwegian Sea and the Arctic Ocean at a time when proxy evidence suggests vigorous Atlantic meridional overturning circulation. Our reconstruction shows that massive marine-based ice sheets can collapse in as little as 300–500 years.

大冰盖坍塌引起的海平面迅速上升对人类社会构成了威胁。在上一个冰期期间，全球海平面上升速率在1A融水脉冲期间达到了超过4 cm yr ^-1，这与大约14650年前的伯灵变暖事件相吻合。但是，已证明融水的来源难以捉摸，欧亚冰盖的贡献被认为是微不足道的。在这里，我们介绍了挪威海的区域碳14标定曲线，并重新标定了海洋¹⁴与欧亚冰原撤退相关的C个日期。我们发现，欧亚冰原的海基部分在伯灵过渡期坍塌，在500年中损失了4.5-7.9 m海平面当量（SLE）。在峰值融化过程中，丢失了3.3–6.7 m SLE的冰，这可能解释了多达1A的融水脉冲。在代理人证据表明大西洋子午翻转活跃的时候，在300年中平均融水流量为0.2 Sv注入了挪威海和北冰洋。我们的重建表明，巨大的海洋冰盖可能在300-500年内坍塌。