Late Holocene reexpansion of the Laurentide Ice Sheet
Nicolás E. Young, Gifford H. Miller, Martha Raynolds, Helga Bueltmann, Scott J. Lehman, Jonathan H. Raberg, Kylie Seward, Simon L. Pendleton, John T. Andrews, Patrick J. Webber, Joerg M. SchaeferDuring interglaciations, the Laurentide Ice Sheet (LIS), which is the largest of the Pleistocene ice sheets, retreats to Arctic Canada, where it achieves a minimum configuration. The reexpansion of the LIS following this minimum marks the start of the next glaciation. Here, we show that the last remaining remnant of the most recent LIS, Barnes Ice Cap (Baffin Island, Canada), achieved its minimum interglacial dimensions after ~3.6 thousand years ago, before reexpanding ~2000 years ago, marking the onset of the next glaciation. The new LIS reached maximum dimensions in ~1960 CE, after which anthropogenic summer warming resulted in a negative mass balance, ice margin recession, and the termination of the next glaciation. The demise of the next glaciation, despite the ongoing decline in summer insolation, illustrates the influence of anomalous greenhouse gas forcing on climate.