Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA.
Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA. Department of Earth and Environmental Sciences, Columbia University, 61 Route 9W, Palisades, NY 10964, USA.
Science. 2014 Jul 18;345(6194):318-22. doi: 10.1126/science.1249770. Epub 2014 Jun 26.
The mid-Pleistocene transition (MPT) marked a fundamental change in glacial-interglacial periodicity, when it increased from ~41-thousand-year to 100-thousand-year cycles and developed higher-amplitude climate variability without substantial changes in the Milankovitch forcing. Here, we document, by using Nd isotopes, a major disruption of the ocean thermohaline circulation (THC) system during the MPT between marine isotope stages (MISs) 25 and 21 at ~950 to 860 thousand years ago, which effectively marks the first 100-thousand-year cycle, including an exceptional weakening through a critical interglacial (MIS 23) at ~900 thousand years ago. Its recovery into the post-MPT 100-thousand-year world is characterized by continued weak glacial THC. The MPT ocean circulation crisis facilitated the coeval drawdown of atmospheric CO2 and high-latitude ice sheet growth, generating the conditions that stabilized 100-thousand-year cycles.
中更新世过渡期（MPT）标志着冰川间冰期周期性的根本变化，当时它从约 41000 年周期增加到 100000 年周期，并在米兰科维奇强迫没有实质性变化的情况下发展出更高振幅的气候变化。在这里，我们通过使用 Nd 同位素记录了在大约 950 到 860 万年前的 MPT 期间海洋热盐环流（THC）系统的重大中断，这有效地标志着第一个 100000 年周期，包括大约 900 万年前异常减弱的关键间冰期（MIS 23）。它恢复到 MPT 后的 100000 年世界的特点是继续减弱的冰川 THC。MPT 海洋环流危机促进了同期大气 CO2 的减少和高纬度冰盖的增长，为稳定 100000 年周期创造了条件。
