El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South
Paleoclimate archives, such as high-resolution ice core records, provide a means to investigate past climate variability. Until recently, the Law Dome (Dome Summit South site) ice core record remained one of few millennial-length high-resolution coastal records in East Antarctica. A new ice core dri...
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Copernicus GmbH
2023
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ftanucanberra:oai:openresearch-repository.anu.edu.au:1885/292247 2023-06-18T03:38:02+02:00 El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South Crockart, Camilla K Vance, Tessa Fraser, Alexander D Abram, Nerilie Criscitiello, Alison S Curran, Mark A J Favier, Vincent Gallant, Ailie J. E. Kittel, Christoph Kjaer, Helle Astrid Klekociuk, Andrew R 2023-05-30T03:59:49Z application/pdf http://hdl.handle.net/1885/292247 https://doi.org/10.5194/cp-17-1795-2021 https://openresearch-repository.anu.edu.au/bitstream/1885/292247/3/cp-17-1795-2021.pdf.jpg en_AU eng Copernicus GmbH http://purl.org/au-research/grants/arc/DP180102522 1814-9324 http://hdl.handle.net/1885/292247 doi:10.5194/cp-17-1795-2021 https://openresearch-repository.anu.edu.au/bitstream/1885/292247/3/cp-17-1795-2021.pdf.jpg © Author(s) 2021. https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License Climate of the Past Journal article 2023 ftanucanberra https://doi.org/10.5194/cp-17-1795-2021 2023-06-05T22:15:44Z Paleoclimate archives, such as high-resolution ice core records, provide a means to investigate past climate variability. Until recently, the Law Dome (Dome Summit South site) ice core record remained one of few millennial-length high-resolution coastal records in East Antarctica. A new ice core drilled in 2017/2018 at Mount Brown South, approximately 1000 km west of Law Dome, provides an additional high-resolution record that will likely span the last millennium in the Indian Ocean sector of East Antarctica. Here, we compare snow accumulation rates and sea salt concentrations in the upper portion (similar to 20 m) of three Mount Brown South ice cores and an updated Law Dome record over the period 1975-2016. Annual sea salt concentrations from the Mount Brown South site record preserve a stronger signal for the El Nino-Southern Oscillation (ENSO; austral winter and spring, r = 0.533, p < 0.001, Multivariate El Nino Index) compared to a previously defined Law Dome record of summer sea salt concentrations (November-February, r = 0.398, p = 0.010, Southern Oscillation Index). The Mount Brown South site record and Law Dome record preserve inverse signals for the ENSO, possibly due to longitudinal variability in meridional transport in the southern Indian Ocean, although further analysis is needed to confirm this. We suggest that ENSO-related sea surface temperature anomalies in the equatorial Pacific drive atmospheric teleconnections in the southern mid-latitudes. These anomalies are associated with a weakening (strengthening) of regional westerly winds to the north of Mount Brown South that correspond to years of low (high) sea salt deposition at Mount Brown South during La Nina (El Nino) events. The extended Mount Brown South annual sea salt record (when complete) may offer a new proxy record for reconstructions of the ENSO over the recent millennium, along with improved understanding of regional atmospheric variability in the southern Indian Ocean, in addition to that derived from Law Dome. Camilla K. ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica ice core Australian National University: ANU Digital Collections Antarctic East Antarctica Austral Pacific Indian Law Dome ENVELOPE(112.833,112.833,-66.733,-66.733) South Ice ENVELOPE(-29.867,-29.867,-81.950,-81.950) Mount Brown ENVELOPE(86.000,86.000,-68.617,-68.617) Climate of the Past 17 5 1795 1818 |
institution |
Open Polar |
collection |
Australian National University: ANU Digital Collections |
op_collection_id |
ftanucanberra |
language |
English |
description |
Paleoclimate archives, such as high-resolution ice core records, provide a means to investigate past climate variability. Until recently, the Law Dome (Dome Summit South site) ice core record remained one of few millennial-length high-resolution coastal records in East Antarctica. A new ice core drilled in 2017/2018 at Mount Brown South, approximately 1000 km west of Law Dome, provides an additional high-resolution record that will likely span the last millennium in the Indian Ocean sector of East Antarctica. Here, we compare snow accumulation rates and sea salt concentrations in the upper portion (similar to 20 m) of three Mount Brown South ice cores and an updated Law Dome record over the period 1975-2016. Annual sea salt concentrations from the Mount Brown South site record preserve a stronger signal for the El Nino-Southern Oscillation (ENSO; austral winter and spring, r = 0.533, p < 0.001, Multivariate El Nino Index) compared to a previously defined Law Dome record of summer sea salt concentrations (November-February, r = 0.398, p = 0.010, Southern Oscillation Index). The Mount Brown South site record and Law Dome record preserve inverse signals for the ENSO, possibly due to longitudinal variability in meridional transport in the southern Indian Ocean, although further analysis is needed to confirm this. We suggest that ENSO-related sea surface temperature anomalies in the equatorial Pacific drive atmospheric teleconnections in the southern mid-latitudes. These anomalies are associated with a weakening (strengthening) of regional westerly winds to the north of Mount Brown South that correspond to years of low (high) sea salt deposition at Mount Brown South during La Nina (El Nino) events. The extended Mount Brown South annual sea salt record (when complete) may offer a new proxy record for reconstructions of the ENSO over the recent millennium, along with improved understanding of regional atmospheric variability in the southern Indian Ocean, in addition to that derived from Law Dome. Camilla K. ... |
format |
Article in Journal/Newspaper |
author |
Crockart, Camilla K Vance, Tessa Fraser, Alexander D Abram, Nerilie Criscitiello, Alison S Curran, Mark A J Favier, Vincent Gallant, Ailie J. E. Kittel, Christoph Kjaer, Helle Astrid Klekociuk, Andrew R |
spellingShingle |
Crockart, Camilla K Vance, Tessa Fraser, Alexander D Abram, Nerilie Criscitiello, Alison S Curran, Mark A J Favier, Vincent Gallant, Ailie J. E. Kittel, Christoph Kjaer, Helle Astrid Klekociuk, Andrew R El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
author_facet |
Crockart, Camilla K Vance, Tessa Fraser, Alexander D Abram, Nerilie Criscitiello, Alison S Curran, Mark A J Favier, Vincent Gallant, Ailie J. E. Kittel, Christoph Kjaer, Helle Astrid Klekociuk, Andrew R |
author_sort |
Crockart, Camilla K |
title |
El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
title_short |
El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
title_full |
El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
title_fullStr |
El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
title_full_unstemmed |
El Nino-Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South |
title_sort |
el nino-southern oscillation signal in a new east antarctic ice core, mount brown south |
publisher |
Copernicus GmbH |
publishDate |
2023 |
url |
http://hdl.handle.net/1885/292247 https://doi.org/10.5194/cp-17-1795-2021 https://openresearch-repository.anu.edu.au/bitstream/1885/292247/3/cp-17-1795-2021.pdf.jpg |
long_lat |
ENVELOPE(112.833,112.833,-66.733,-66.733) ENVELOPE(-29.867,-29.867,-81.950,-81.950) ENVELOPE(86.000,86.000,-68.617,-68.617) |
geographic |
Antarctic East Antarctica Austral Pacific Indian Law Dome South Ice Mount Brown |
geographic_facet |
Antarctic East Antarctica Austral Pacific Indian Law Dome South Ice Mount Brown |
genre |
Antarc* Antarctic Antarctica East Antarctica ice core |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica ice core |
op_source |
Climate of the Past |
op_relation |
http://purl.org/au-research/grants/arc/DP180102522 1814-9324 http://hdl.handle.net/1885/292247 doi:10.5194/cp-17-1795-2021 https://openresearch-repository.anu.edu.au/bitstream/1885/292247/3/cp-17-1795-2021.pdf.jpg |
op_rights |
© Author(s) 2021. https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License |
op_doi |
https://doi.org/10.5194/cp-17-1795-2021 |
container_title |
Climate of the Past |
container_volume |
17 |
container_issue |
5 |
container_start_page |
1795 |
op_container_end_page |
1818 |
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