Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years
Antarctica is well known to be highly susceptible to atmospheric and oceanic warming. However, due to the lack of long-term and in situ meteorological observations, little is known about the magnitude of the warming and the meteorological conditions in the intersection region between the Antarctic P...
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ftcopernicus:oai:publications.copernicus.org:tc70811 2023-05-15T13:55:28+02:00 Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years Hoffmann, Kirstin Fernandoy, Francisco Meyer, Hanno Thomas, Elizabeth R. Aliaga, Marcelo Tetzner, Dieter Freitag, Johannes Opel, Thomas Arigony-Neto, Jorge Göbel, Christian Florian Jaña, Ricardo Rodríguez Oroz, Delia Tuckwell, Rebecca Ludlow, Emily McConnell, Joseph R. Schneider, Christoph 2020-03-09 application/pdf https://doi.org/10.5194/tc-14-881-2020 https://tc.copernicus.org/articles/14/881/2020/ eng eng doi:10.5194/tc-14-881-2020 https://tc.copernicus.org/articles/14/881/2020/ eISSN: 1994-0424 Text 2020 ftcopernicus https://doi.org/10.5194/tc-14-881-2020 2020-07-20T16:22:22Z Antarctica is well known to be highly susceptible to atmospheric and oceanic warming. However, due to the lack of long-term and in situ meteorological observations, little is known about the magnitude of the warming and the meteorological conditions in the intersection region between the Antarctic Peninsula (AP), the West Antarctic Ice Sheet (WAIS) and the East Antarctic Ice Sheet (EAIS). Here we present new stable water isotope data ( δ 18 O , δ D , d excess) and accumulation rates from firn cores in the Union Glacier (UG) region, located in the Ellsworth Mountains at the northern edge of the WAIS. The firn core stable oxygen isotopes and the d excess exhibit no statistically significant trend for the period 1980–2014, suggesting that regional changes in near-surface air temperature and moisture source variability have been small during the last 35 years. Backward trajectory modelling revealed the Weddell Sea sector, Coats Land and Dronning Maud Land (DML) to be the main moisture source regions for the study site throughout the year. We found that mean annual δ 18 O ( δ D ) values in the UG region are negatively correlated with sea ice concentrations (SICs) in the northern Weddell Sea but not influenced by large-scale modes of climate variability such as the Southern Annular Mode (SAM) and the El Niño–Southern Oscillation (ENSO). Only mean annual d -excess values show a weak positive correlation with the SAM. On average annual snow accumulation in the UG region amounts to 0.245 m w.e. a −1 in 1980–2014 and has slightly decreased during this period. It is only weakly related to sea ice conditions in the Weddell Sea sector and not correlated with SAM and ENSO. We conclude that neither the rapid warming nor the large increases in snow accumulation observed on the AP and in West Antarctica during the last decades have extended inland to the Ellsworth Mountains. Hence, the UG region, although located at the northern edge of the WAIS and relatively close to the AP, exhibits rather stable climate characteristics similar to those observed in East Antarctica. Text Antarc* Antarctic Antarctic Peninsula Antarctica DML Dronning Maud Land East Antarctica Ice Sheet Sea ice Union Glacier Weddell Sea West Antarctica Copernicus Publications: E-Journals Antarctic Antarctic Peninsula Coats Land ENVELOPE(-27.500,-27.500,-77.000,-77.000) Dronning Maud Land East Antarctic Ice Sheet East Antarctica Ellsworth Mountains ENVELOPE(-85.000,-85.000,-78.750,-78.750) The Antarctic Union Glacier ENVELOPE(-82.500,-82.500,-79.750,-79.750) Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica The Cryosphere 14 3 881 904 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Antarctica is well known to be highly susceptible to atmospheric and oceanic warming. However, due to the lack of long-term and in situ meteorological observations, little is known about the magnitude of the warming and the meteorological conditions in the intersection region between the Antarctic Peninsula (AP), the West Antarctic Ice Sheet (WAIS) and the East Antarctic Ice Sheet (EAIS). Here we present new stable water isotope data ( δ 18 O , δ D , d excess) and accumulation rates from firn cores in the Union Glacier (UG) region, located in the Ellsworth Mountains at the northern edge of the WAIS. The firn core stable oxygen isotopes and the d excess exhibit no statistically significant trend for the period 1980–2014, suggesting that regional changes in near-surface air temperature and moisture source variability have been small during the last 35 years. Backward trajectory modelling revealed the Weddell Sea sector, Coats Land and Dronning Maud Land (DML) to be the main moisture source regions for the study site throughout the year. We found that mean annual δ 18 O ( δ D ) values in the UG region are negatively correlated with sea ice concentrations (SICs) in the northern Weddell Sea but not influenced by large-scale modes of climate variability such as the Southern Annular Mode (SAM) and the El Niño–Southern Oscillation (ENSO). Only mean annual d -excess values show a weak positive correlation with the SAM. On average annual snow accumulation in the UG region amounts to 0.245 m w.e. a −1 in 1980–2014 and has slightly decreased during this period. It is only weakly related to sea ice conditions in the Weddell Sea sector and not correlated with SAM and ENSO. We conclude that neither the rapid warming nor the large increases in snow accumulation observed on the AP and in West Antarctica during the last decades have extended inland to the Ellsworth Mountains. Hence, the UG region, although located at the northern edge of the WAIS and relatively close to the AP, exhibits rather stable climate characteristics similar to those observed in East Antarctica. |
format |
Text |
author |
Hoffmann, Kirstin Fernandoy, Francisco Meyer, Hanno Thomas, Elizabeth R. Aliaga, Marcelo Tetzner, Dieter Freitag, Johannes Opel, Thomas Arigony-Neto, Jorge Göbel, Christian Florian Jaña, Ricardo Rodríguez Oroz, Delia Tuckwell, Rebecca Ludlow, Emily McConnell, Joseph R. Schneider, Christoph |
spellingShingle |
Hoffmann, Kirstin Fernandoy, Francisco Meyer, Hanno Thomas, Elizabeth R. Aliaga, Marcelo Tetzner, Dieter Freitag, Johannes Opel, Thomas Arigony-Neto, Jorge Göbel, Christian Florian Jaña, Ricardo Rodríguez Oroz, Delia Tuckwell, Rebecca Ludlow, Emily McConnell, Joseph R. Schneider, Christoph Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
author_facet |
Hoffmann, Kirstin Fernandoy, Francisco Meyer, Hanno Thomas, Elizabeth R. Aliaga, Marcelo Tetzner, Dieter Freitag, Johannes Opel, Thomas Arigony-Neto, Jorge Göbel, Christian Florian Jaña, Ricardo Rodríguez Oroz, Delia Tuckwell, Rebecca Ludlow, Emily McConnell, Joseph R. Schneider, Christoph |
author_sort |
Hoffmann, Kirstin |
title |
Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
title_short |
Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
title_full |
Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
title_fullStr |
Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
title_full_unstemmed |
Stable water isotopes and accumulation rates in the Union Glacier region, Ellsworth Mountains, West Antarctica, over the last 35 years |
title_sort |
stable water isotopes and accumulation rates in the union glacier region, ellsworth mountains, west antarctica, over the last 35 years |
publishDate |
2020 |
url |
https://doi.org/10.5194/tc-14-881-2020 https://tc.copernicus.org/articles/14/881/2020/ |
long_lat |
ENVELOPE(-27.500,-27.500,-77.000,-77.000) ENVELOPE(-85.000,-85.000,-78.750,-78.750) ENVELOPE(-82.500,-82.500,-79.750,-79.750) |
geographic |
Antarctic Antarctic Peninsula Coats Land Dronning Maud Land East Antarctic Ice Sheet East Antarctica Ellsworth Mountains The Antarctic Union Glacier Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Antarctic Antarctic Peninsula Coats Land Dronning Maud Land East Antarctic Ice Sheet East Antarctica Ellsworth Mountains The Antarctic Union Glacier Weddell Weddell Sea West Antarctic Ice Sheet West Antarctica |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica DML Dronning Maud Land East Antarctica Ice Sheet Sea ice Union Glacier Weddell Sea West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica DML Dronning Maud Land East Antarctica Ice Sheet Sea ice Union Glacier Weddell Sea West Antarctica |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-14-881-2020 https://tc.copernicus.org/articles/14/881/2020/ |
op_doi |
https://doi.org/10.5194/tc-14-881-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
3 |
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881 |
op_container_end_page |
904 |
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1766262096139386880 |