Cenozoic sea-level and cryospheric evolution from deep-sea geochemical and continental margin records

Kenneth G Miller; James V Browning; W John Schmelz; Robert E Kopp; Gregory S Mountain; James D Wright

doi:10.1126/sciadv.aaz1346

Cenozoic sea-level and cryospheric evolution from deep-sea geochemical and continental margin records

Sci Adv. 2020 May 15;6(20):eaaz1346. doi: 10.1126/sciadv.aaz1346. eCollection 2020 May.

Authors

Kenneth G Miller^{1

2}, James V Browning^{1

2}, W John Schmelz^{1

2}, Robert E Kopp^{1

2}, Gregory S Mountain^{1

2}, James D Wright^{1

2}

Affiliations

¹ Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ 08854, USA.
² Institute of Earth, Ocean, and Atmospheric Sciences, Rutgers University, New Brunswick, NJ 08901, USA.

Abstract

Using Pacific benthic foraminiferal δ¹⁸O and Mg/Ca records, we derive a Cenozoic (66 Ma) global mean sea level (GMSL) estimate that records evolution from an ice-free Early Eocene to Quaternary bipolar ice sheets. These GMSL estimates are statistically similar to "backstripped" estimates from continental margins accounting for compaction, loading, and thermal subsidence. Peak warmth, elevated GMSL, high CO₂, and ice-free "Hothouse" conditions (56 to 48 Ma) were followed by "Cool Greenhouse" (48 to 34 Ma) ice sheets (10 to 30 m changes). Continental-scale ice sheets ("Icehouse") began ~34 Ma (>50 m changes), permanent East Antarctic ice sheets at 12.8 Ma, and bipolar glaciation at 2.5 Ma. The largest GMSL fall (27 to 20 ka; ~130 m) was followed by a >40 mm/yr rise (19 to 10 ka), a slowing (10 to 2 ka), and a stillstand until ~1900 CE, when rates began to rise. High long-term CO₂ caused warm climates and high sea levels, with sea-level variability dominated by periodic Milankovitch cycles.

Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

Publication types

Review