Stable Biological Production in the Eastern Equatorial Pacific Across the Plio‐Pleistocene Transition (∼3.35–2.0 Ma)
نویسندگان
چکیده
Upwelling within the Eastern Equatorial Pacific (EEP) Ocean is a key factor for Earth's climate because it supports >10% of present-day biological production. The dynamics upwelling in EEP across Plio-Pleistocene transition—an interval particularly relevant understanding near-future warming due to Anthropocene-like atmospheric carbon-dioxide levels—have been intensively studied region east East Rise. In contrast, changes equatorial regime open west this oceanographic barrier have received markedly less attention. We therefore provide new proxy records from Drilling Program Site 849 located open-ocean regime. Our target (∼3.35–2.0 Ma) covers transition characterized by intensification Northern Hemisphere Glaciation (iNHG). use benthic δ18O values generate new, high-resolution age model 849, and sand-accumulation rates together with δ13C evaluate net export Although showing temporary substantial glacial-interglacial variations, our indicate stability production on secular timescales iNHG. suggest following processes controlled long-term evolution primary productivity at 849. First, nutrient high latitudes EEP; second, successive shoaling nutricline during interval; third, simultaneous reduction dust-borne iron input.
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ژورنال
عنوان ژورنال: Paleoceanography and paleoclimatology
سال: 2021
ISSN: ['2572-4517', '2572-4525']
DOI: https://doi.org/10.1029/2020pa003965