Effective diffusivity of sulfuric acid in Antarctic ice cores
Volcanic deposition of sulfuric acid in ice cores is important both for understanding past volcanic activity and for synchronizing ice core timescales. Sulfuric acid has a low eutectic point, so it can potentially exist in liquid at grain boundaries and veins, accelerating chemical diffusion. A high...
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00063888 2023-05-15T13:49:22+02:00 Effective diffusivity of sulfuric acid in Antarctic ice cores Fudge, Tyler J. Sauvage, Raphael Vu, Linh Hills, Benjamin H. Severi, Mirko Waddington, Edwin D. 2022-12 electronic https://doi.org/10.5194/egusphere-2022-1219 https://noa.gwlb.de/receive/cop_mods_00063888 https://egusphere.copernicus.org/preprints/egusphere-2022-1219/egusphere-2022-1219.pdf eng eng Copernicus Publications https://doi.org/10.5194/egusphere-2022-1219 https://noa.gwlb.de/receive/cop_mods_00063888 https://egusphere.copernicus.org/preprints/egusphere-2022-1219/egusphere-2022-1219.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/restrictedAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2022 ftnonlinearchiv https://doi.org/10.5194/egusphere-2022-1219 2022-12-12T00:12:45Z Volcanic deposition of sulfuric acid in ice cores is important both for understanding past volcanic activity and for synchronizing ice core timescales. Sulfuric acid has a low eutectic point, so it can potentially exist in liquid at grain boundaries and veins, accelerating chemical diffusion. A high effective diffusivity would allow post-depositional diffusion to obscure the climate history and the peak matching among older portions of ice cores. Here, we use records of sulfate from the EPICA Dome C (EDC) ice core to estimate the effective diffusivity of sulfuric acid in ice. We focus on EDC because multiple glacial-interglacial cycles are preserved, allowing analysis for long timescales and deposition in similar climates. We calculate the mean concentration gradient and the width of prominent volcanic events, and analyze the evolution of each with depth/age. We find the effective diffusivities for interglacials and glacial maximums to be 5 ± 2 × 10-9 m2 a-1, an order of magnitude lower than a previous estimate derived from the Holocene portion of EDC (Barnes et al., 2003). The effective diffusivity may be even smaller if artificial diffusion from the sampling is accounted for. Effective diffusivity is not obviously affected by the ice temperature until about -10 °C, 3000 m depth, which is also where anomalous sulfate peaks begin to be observed (Traversi et al., 2009). Low effective diffusivity suggests that sulfuric acid is not readily diffusing in liquid-like veins in the upper portions of the Antarctic ice sheet and that records may be preserved in deep, old ice if the ice temperature remains well below the pressure melting point. Article in Journal/Newspaper Antarc* Antarctic EPICA ice core Ice Sheet Niedersächsisches Online-Archiv NOA Antarctic The Antarctic |
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article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Fudge, Tyler J. Sauvage, Raphael Vu, Linh Hills, Benjamin H. Severi, Mirko Waddington, Edwin D. Effective diffusivity of sulfuric acid in Antarctic ice cores |
topic_facet |
article Verlagsveröffentlichung |
description |
Volcanic deposition of sulfuric acid in ice cores is important both for understanding past volcanic activity and for synchronizing ice core timescales. Sulfuric acid has a low eutectic point, so it can potentially exist in liquid at grain boundaries and veins, accelerating chemical diffusion. A high effective diffusivity would allow post-depositional diffusion to obscure the climate history and the peak matching among older portions of ice cores. Here, we use records of sulfate from the EPICA Dome C (EDC) ice core to estimate the effective diffusivity of sulfuric acid in ice. We focus on EDC because multiple glacial-interglacial cycles are preserved, allowing analysis for long timescales and deposition in similar climates. We calculate the mean concentration gradient and the width of prominent volcanic events, and analyze the evolution of each with depth/age. We find the effective diffusivities for interglacials and glacial maximums to be 5 ± 2 × 10-9 m2 a-1, an order of magnitude lower than a previous estimate derived from the Holocene portion of EDC (Barnes et al., 2003). The effective diffusivity may be even smaller if artificial diffusion from the sampling is accounted for. Effective diffusivity is not obviously affected by the ice temperature until about -10 °C, 3000 m depth, which is also where anomalous sulfate peaks begin to be observed (Traversi et al., 2009). Low effective diffusivity suggests that sulfuric acid is not readily diffusing in liquid-like veins in the upper portions of the Antarctic ice sheet and that records may be preserved in deep, old ice if the ice temperature remains well below the pressure melting point. |
format |
Article in Journal/Newspaper |
author |
Fudge, Tyler J. Sauvage, Raphael Vu, Linh Hills, Benjamin H. Severi, Mirko Waddington, Edwin D. |
author_facet |
Fudge, Tyler J. Sauvage, Raphael Vu, Linh Hills, Benjamin H. Severi, Mirko Waddington, Edwin D. |
author_sort |
Fudge, Tyler J. |
title |
Effective diffusivity of sulfuric acid in Antarctic ice cores |
title_short |
Effective diffusivity of sulfuric acid in Antarctic ice cores |
title_full |
Effective diffusivity of sulfuric acid in Antarctic ice cores |
title_fullStr |
Effective diffusivity of sulfuric acid in Antarctic ice cores |
title_full_unstemmed |
Effective diffusivity of sulfuric acid in Antarctic ice cores |
title_sort |
effective diffusivity of sulfuric acid in antarctic ice cores |
publisher |
Copernicus Publications |
publishDate |
2022 |
url |
https://doi.org/10.5194/egusphere-2022-1219 https://noa.gwlb.de/receive/cop_mods_00063888 https://egusphere.copernicus.org/preprints/egusphere-2022-1219/egusphere-2022-1219.pdf |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic EPICA ice core Ice Sheet |
genre_facet |
Antarc* Antarctic EPICA ice core Ice Sheet |
op_relation |
https://doi.org/10.5194/egusphere-2022-1219 https://noa.gwlb.de/receive/cop_mods_00063888 https://egusphere.copernicus.org/preprints/egusphere-2022-1219/egusphere-2022-1219.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/restrictedAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/egusphere-2022-1219 |
_version_ |
1766251246147076096 |