West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability?
Western Antarctica has been experiencing significant warming for at least the past fifty years. While higher Net Surface Mass Balance (SMB) over West Antarctica during this period of warming is expected, SMB reconstructions from ice cores reveal a more complex pattern during the period of warming. T...
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ftbrighamyoung:oai:scholarsarchive.byu.edu:etd-5381 2023-07-23T04:15:43+02:00 West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? Carpenter, McLean Kent 2014-03-01T08:00:00Z application/pdf https://scholarsarchive.byu.edu/etd/4382 https://scholarsarchive.byu.edu/context/etd/article/5381/viewcontent/etd6775.pdf unknown BYU ScholarsArchive https://scholarsarchive.byu.edu/etd/4382 https://scholarsarchive.byu.edu/context/etd/article/5381/viewcontent/etd6775.pdf http://lib.byu.edu/about/copyright/ Theses and Dissertations Climate Variability West Antarctica Surface Mass Balance Ice Core Geology text 2014 ftbrighamyoung 2023-07-03T22:22:45Z Western Antarctica has been experiencing significant warming for at least the past fifty years. While higher Net Surface Mass Balance (SMB) over West Antarctica during this period of warming is expected, SMB reconstructions from ice cores reveal a more complex pattern during the period of warming. The mechanisms giving rise to SMB variability over the West Antarctic Ice Sheet (WAIS) are not well understood due to lack of instrumental data. The Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO) are believed to contribute to WAIS SMB variability but the assumption has not been rigorously tested. SMB during years where SAM and ENSO are in extreme phases is compared to average SMB from the period 1979-2010. Additionally, atmospheric circulation anomalies are used to assess what circulation patterns accompany extreme modes of climate during the same period. The results suggest that significantly lower SMB occurs when SAM is in an extremely positive phase or ENSO is in an extremely negative phase. Additionally, atmospheric circulation anomalies show that certain circulation patterns accompany extreme modes of climate, which contribute to SMB variability over the WAIS. Ultimately, the location of low and high pressure cells is the best predictor for extreme accumulation events over the WAIS. These results are verified by assessing observed net SMB trends from a network of firn cores located from the central WAIS. Seven new firn cores are added to improve the spatial network of regional net SMB measurements. Reconstructed net SMB is calculated from new firn core records, and compared to the existing cores. The new suite of preliminary firn core records show the same significant decreasing trend that is observed in existing cores. This represents a negative region-wide SMB trend that is likely in part due to trends in SAM and ENSO. Text Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica Brigham Young University (BYU): ScholarsArchive Antarctic West Antarctic Ice Sheet West Antarctica |
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Brigham Young University (BYU): ScholarsArchive |
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Climate Variability West Antarctica Surface Mass Balance Ice Core Geology |
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Climate Variability West Antarctica Surface Mass Balance Ice Core Geology Carpenter, McLean Kent West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
topic_facet |
Climate Variability West Antarctica Surface Mass Balance Ice Core Geology |
description |
Western Antarctica has been experiencing significant warming for at least the past fifty years. While higher Net Surface Mass Balance (SMB) over West Antarctica during this period of warming is expected, SMB reconstructions from ice cores reveal a more complex pattern during the period of warming. The mechanisms giving rise to SMB variability over the West Antarctic Ice Sheet (WAIS) are not well understood due to lack of instrumental data. The Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO) are believed to contribute to WAIS SMB variability but the assumption has not been rigorously tested. SMB during years where SAM and ENSO are in extreme phases is compared to average SMB from the period 1979-2010. Additionally, atmospheric circulation anomalies are used to assess what circulation patterns accompany extreme modes of climate during the same period. The results suggest that significantly lower SMB occurs when SAM is in an extremely positive phase or ENSO is in an extremely negative phase. Additionally, atmospheric circulation anomalies show that certain circulation patterns accompany extreme modes of climate, which contribute to SMB variability over the WAIS. Ultimately, the location of low and high pressure cells is the best predictor for extreme accumulation events over the WAIS. These results are verified by assessing observed net SMB trends from a network of firn cores located from the central WAIS. Seven new firn cores are added to improve the spatial network of regional net SMB measurements. Reconstructed net SMB is calculated from new firn core records, and compared to the existing cores. The new suite of preliminary firn core records show the same significant decreasing trend that is observed in existing cores. This represents a negative region-wide SMB trend that is likely in part due to trends in SAM and ENSO. |
format |
Text |
author |
Carpenter, McLean Kent |
author_facet |
Carpenter, McLean Kent |
author_sort |
Carpenter, McLean Kent |
title |
West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
title_short |
West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
title_full |
West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
title_fullStr |
West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
title_full_unstemmed |
West Antarctic Surface Mass Balance: Do Synoptic Scale Modes of Climate Contribute to Observed Variability? |
title_sort |
west antarctic surface mass balance: do synoptic scale modes of climate contribute to observed variability? |
publisher |
BYU ScholarsArchive |
publishDate |
2014 |
url |
https://scholarsarchive.byu.edu/etd/4382 https://scholarsarchive.byu.edu/context/etd/article/5381/viewcontent/etd6775.pdf |
geographic |
Antarctic West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Antarctic West Antarctic Ice Sheet West Antarctica |
genre |
Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica |
op_source |
Theses and Dissertations |
op_relation |
https://scholarsarchive.byu.edu/etd/4382 https://scholarsarchive.byu.edu/context/etd/article/5381/viewcontent/etd6775.pdf |
op_rights |
http://lib.byu.edu/about/copyright/ |
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