Intensified aridity over the Indo-Pacific Warm Pool controlled by ice-sheet expansion during the Last Glacial Maximum
(2022) In Global and Planetary Change 217.- Abstract
The magnitude, direction and cause of precipitation changes across the Indo-Pacific Warm Pool (IPWP) during the Last Glacial Maximum (LGM) remain elusive. In particular, it is still inconclusive whether tropical or extra-tropical factors controlled such precipitation changes. Determining the spatio-temporal distribution of precipitation in the IPWP during the LGM is a valid strategy to address this issue, but the existing precipitation records are dominantly from maritime continents and marginal seas, with few data from pelagic oceans. In order to fill this gap, we analyzed the oxygen isotopic compositions of single Ethmodiscus rex diatom frustules (δ18OE. rex) from a sediment core (WPD-03) consisting of laminated... (More)
The magnitude, direction and cause of precipitation changes across the Indo-Pacific Warm Pool (IPWP) during the Last Glacial Maximum (LGM) remain elusive. In particular, it is still inconclusive whether tropical or extra-tropical factors controlled such precipitation changes. Determining the spatio-temporal distribution of precipitation in the IPWP during the LGM is a valid strategy to address this issue, but the existing precipitation records are dominantly from maritime continents and marginal seas, with few data from pelagic oceans. In order to fill this gap, we analyzed the oxygen isotopic compositions of single Ethmodiscus rex diatom frustules (δ18OE. rex) from a sediment core (WPD-03) consisting of laminated diatom mats (LDMs) in the eastern Philippine Sea (EPS). δ18OE. rex was controlled mainly by sea-surface salinity variation and, thus, can reflect open-ocean precipitation changes across the IPWP. Our precipitation proxy records, in combination with existing published data, reveal spatial patterns of precipitation change that indicate overall drying across the IPWP during the LGM. Based on a comparison of paleoclimatic records with modeling results, we propose that extra-tropical factors (ice-sheet size) controlled precipitation variability in the IPWP during the LGM through a combination of zonal shifts of ENSO and meridional migration of the ITCZ. Strong aridity during the LGM prevented formation of a subsurface barrier layer and, hence, allowed accessing of sufficient nutrients to surface waters, stimulating blooms of E. rex and subsequent formation of LDMs in the IPWP. These findings suggest an important role for high-latitude climate in the tropical hydrological cycle during the LGM.
(Less)
- author
- organization
- publishing date
- 2022-10
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Diatom blooms, High-latitude forcing, Model simulation, Sea-surface salinity, Tropical hydroclimate, Tropical West Pacific
- in
- Global and Planetary Change
- volume
- 217
- article number
- 103952
- publisher
- Elsevier
- external identifiers
-
- scopus:85138463656
- ISSN
- 0921-8181
- DOI
- 10.1016/j.gloplacha.2022.103952
- language
- English
- LU publication?
- yes
- id
- 77723db9-011e-44fc-ab2c-6b1fb06189b2
- date added to LUP
- 2022-12-27 14:05:37
- date last changed
- 2023-05-10 11:09:56
@article{77723db9-011e-44fc-ab2c-6b1fb06189b2,
abstract = {{<p>The magnitude, direction and cause of precipitation changes across the Indo-Pacific Warm Pool (IPWP) during the Last Glacial Maximum (LGM) remain elusive. In particular, it is still inconclusive whether tropical or extra-tropical factors controlled such precipitation changes. Determining the spatio-temporal distribution of precipitation in the IPWP during the LGM is a valid strategy to address this issue, but the existing precipitation records are dominantly from maritime continents and marginal seas, with few data from pelagic oceans. In order to fill this gap, we analyzed the oxygen isotopic compositions of single Ethmodiscus rex diatom frustules (δ<sup>18</sup>O<sub>E. rex</sub>) from a sediment core (WPD-03) consisting of laminated diatom mats (LDMs) in the eastern Philippine Sea (EPS). δ<sup>18</sup>O<sub>E. rex</sub> was controlled mainly by sea-surface salinity variation and, thus, can reflect open-ocean precipitation changes across the IPWP. Our precipitation proxy records, in combination with existing published data, reveal spatial patterns of precipitation change that indicate overall drying across the IPWP during the LGM. Based on a comparison of paleoclimatic records with modeling results, we propose that extra-tropical factors (ice-sheet size) controlled precipitation variability in the IPWP during the LGM through a combination of zonal shifts of ENSO and meridional migration of the ITCZ. Strong aridity during the LGM prevented formation of a subsurface barrier layer and, hence, allowed accessing of sufficient nutrients to surface waters, stimulating blooms of E. rex and subsequent formation of LDMs in the IPWP. These findings suggest an important role for high-latitude climate in the tropical hydrological cycle during the LGM.</p>}},
author = {{Xiong, Zhifang and Zhai, Bin and Algeo, Thomas J. and Lu, Zhengyao and Li, Tiegang and Meyer, Hanno and Jiang, Fuqing and Zhang, Peng and Qin, Bingbin and Gong, Xun and Wang, Zhenyan and Jia, Qi}},
issn = {{0921-8181}},
keywords = {{Diatom blooms; High-latitude forcing; Model simulation; Sea-surface salinity; Tropical hydroclimate; Tropical West Pacific}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Global and Planetary Change}},
title = {{Intensified aridity over the Indo-Pacific Warm Pool controlled by ice-sheet expansion during the Last Glacial Maximum}},
url = {{http://dx.doi.org/10.1016/j.gloplacha.2022.103952}},
doi = {{10.1016/j.gloplacha.2022.103952}},
volume = {{217}},
year = {{2022}},
}