Sea surface acidification events in the Andaman Sea associated with the last Toba volcanic activity - Archive ouverte HAL Access content directly
Journal Articles Global and Planetary Change Year : 2024

Sea surface acidification events in the Andaman Sea associated with the last Toba volcanic activity

Abstract

To date, little is known about the impact of super-eruptions on ocean biogeochemistry. Using boron isotopes ratios measured on planktonic foraminifera in the marine sediment core BAR94–25, we provide a high-resolution pH record in the Andaman Sea (North of Sumatra), spanning Marine Isotopic Stage 5 to 3. This transition encompasses the super-eruption of the Toba volcano, 74,000 years ago, making it possible to decipher the potential impact of the super-eruption emissions on the ocean pH for the first time. Our results show that inferred foraminiferal pH values generally follow those predicted by glacial-interglacial CO2 variations. However, several abrupt pH drops coincide with Toba ash deposition. This suggests the occurrence of acidification events possibly related to Toba volcanic sulphur emission episodes. These pH drops are followed by anomalous pH increases, possibly relating to localised increases in seawater alkalinity following the alteration of large ash deposits on land.
Embargoed file
Embargoed file
0 4 15
Year Month Jours
Avant la publication
Saturday, November 30, 2024
Embargoed file
Saturday, November 30, 2024
Please log in to request access to the document

Dates and versions

hal-04581580 , version 1 (30-05-2024)

Identifiers

Cite

Ana Alves, Matthieu Paulhac Buisson, Pascale Louvat, Claire Rollion-Bard, Franck Bassinot, et al.. Sea surface acidification events in the Andaman Sea associated with the last Toba volcanic activity. Global and Planetary Change, 2024, 237, pp.104460. ⟨10.1016/j.gloplacha.2024.104460⟩. ⟨hal-04581580⟩
90 View
1 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More