Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events
We performed an Empirical Orthogonal Function (EOF) analysis to assess the intraseasonal variability of 5–60 day band-pass filtered Antarctic sea-ice concentration in austral winter using a 20-year daily dataset from 1995 to 2014. Zonal wave number 3 dominated in the Antarctic, especially so across...
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2017-10-01
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| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143017000491/type/journal_article |
| _version_ | 1811155891117883392 |
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| author | KENJI BABA JAMES RENWICK |
| author_facet | KENJI BABA JAMES RENWICK |
| author_sort | KENJI BABA |
| collection | DOAJ |
| description | We performed an Empirical Orthogonal Function (EOF) analysis to assess the intraseasonal variability of 5–60 day band-pass filtered Antarctic sea-ice concentration in austral winter using a 20-year daily dataset from 1995 to 2014. Zonal wave number 3 dominated in the Antarctic, especially so across the west Antarctic. Results showed the coexistence of stationary and propagating wave components. A spectral analysis of the first two principal components (PCs) showed a similar structure for periods up to 15 days but generally more power in PC1 at longer periods. Regression analysis upon atmospheric fields using the first two PCs of sea-ice concentration showed a coherent wave number 3 pattern. The spatial phase delay between the sea-ice and mean sea-level pressure patterns suggests that meridional flow and associated temperature advection are important for modulating the sea-ice field. EOF analyses carried out separately for El Niño, La Niña and neutral years, and for Southern Annular Mode positive, negative and neutral periods, suggest that the spatial patterns of wave number 3 shift between subsets. The results also indicate that El Niño-Southern Oscillation and Southern Annular Mode affect stationary wave interactions between sea-ice and atmospheric fields on intraseasonal timescales. |
| first_indexed | 2024-04-10T04:41:12Z |
| format | Article |
| id | doaj.art-d90d8710a2ed49cb9cfc9ab30e7a99f6 |
| institution | Directory Open Access Journal |
| issn | 0022-1430 1727-5652 |
| language | English |
| last_indexed | 2024-04-10T04:41:12Z |
| publishDate | 2017-10-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj.art-d90d8710a2ed49cb9cfc9ab30e7a99f62023-03-09T12:40:28ZengCambridge University PressJournal of Glaciology0022-14301727-56522017-10-016383884610.1017/jog.2017.49Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM eventsKENJI BABA0JAMES RENWICK1College of Agriculture, Food and Environment Sciences, Rakuno Gakuen University, Ebetsu, Hokkaido, Japan School of Geography, Environment and Earth Sciences, Victoria University of Wellington, New ZealandSchool of Geography, Environment and Earth Sciences, Victoria University of Wellington, New ZealandWe performed an Empirical Orthogonal Function (EOF) analysis to assess the intraseasonal variability of 5–60 day band-pass filtered Antarctic sea-ice concentration in austral winter using a 20-year daily dataset from 1995 to 2014. Zonal wave number 3 dominated in the Antarctic, especially so across the west Antarctic. Results showed the coexistence of stationary and propagating wave components. A spectral analysis of the first two principal components (PCs) showed a similar structure for periods up to 15 days but generally more power in PC1 at longer periods. Regression analysis upon atmospheric fields using the first two PCs of sea-ice concentration showed a coherent wave number 3 pattern. The spatial phase delay between the sea-ice and mean sea-level pressure patterns suggests that meridional flow and associated temperature advection are important for modulating the sea-ice field. EOF analyses carried out separately for El Niño, La Niña and neutral years, and for Southern Annular Mode positive, negative and neutral periods, suggest that the spatial patterns of wave number 3 shift between subsets. The results also indicate that El Niño-Southern Oscillation and Southern Annular Mode affect stationary wave interactions between sea-ice and atmospheric fields on intraseasonal timescales.https://www.cambridge.org/core/product/identifier/S0022143017000491/type/journal_articleatmosphere/ice/ocean interactionsclimate changesea ice |
| spellingShingle | KENJI BABA JAMES RENWICK Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events Journal of Glaciology atmosphere/ice/ocean interactions climate change sea ice |
| title | Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events |
| title_full | Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events |
| title_fullStr | Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events |
| title_full_unstemmed | Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events |
| title_short | Aspects of intraseasonal variability of Antarctic sea ice in austral winter related to ENSO and SAM events |
| title_sort | aspects of intraseasonal variability of antarctic sea ice in austral winter related to enso and sam events |
| topic | atmosphere/ice/ocean interactions climate change sea ice |
| url | https://www.cambridge.org/core/product/identifier/S0022143017000491/type/journal_article |
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