The Western Equatorial Pacific (WEP) warm pool, with surface temperatures >28
In the early Pleistocene, global temperature cycles predominantly varied with ~41‐kyr (obliquity‐scale) periodicity. Atmospheric greenhouse gas concentrations likely played a role in these climate cycles; marine sediments provide an indirect geochemical means to estimate early Pleistocene CO2. Here we present a boron isotope‐based record of continuous high‐resolution surface ocean pH and inferred atmospheric CO2changes. Our results show that, within a window of time in the early Pleistocene (1.38–1.54 Ma), pCO2varied with obliquity, confirming that, analogous to late Pleistocene conditions, the carbon cycle and climate covaried at ~1.5 Ma. Pairing the reconstructed early Pleistocene pCO2amplitude (92 ± 13 μatm) with a comparably smaller global surface temperature glacial/interglacial amplitude (3.0 ± 0.5 K) yields a surface temperature change to CO2radiative forcing ratio of
- PAR ID:
- 10460193
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Paleoceanography and Paleoclimatology
- Volume:
- 33
- Issue:
- 11
- ISSN:
- 2572-4517
- Page Range / eLocation ID:
- p. 1270-1291
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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