Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD
Mid-latitude winter atmospheric variability in the South Indian Ocean and southwest Pacific Ocean regions of the circum-Antarctic are reconstructed using sea-salt aerosol concentrations measured in the high resolution Law Dome (DSS) ice core from East Antarctica. The sea-salt aerosol concentration d...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Springer
2004
|
Subjects: | |
Online Access: | http://hdl.handle.net/1959.13/26476 |
id |
ftunivnewcastnsw:uon:895 |
---|---|
record_format |
openpolar |
spelling |
ftunivnewcastnsw:uon:895 2023-05-15T13:54:57+02:00 Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD Goodwin, I. D. van Ommen, T. D. Curran, M. A. J. Mayewski, P. A. 2004 http://hdl.handle.net/1959.13/26476 eng eng Springer Climate Dynamics Vol. 22, Issue 8, p. 783-794 10.1007/s00382-004-0403-3 South Indian Ocean Pacific Ocean Antarctica sea-salt aerosol concentration atmospheric circulation patterns journal article 2004 ftunivnewcastnsw 2018-07-27T00:37:50Z Mid-latitude winter atmospheric variability in the South Indian Ocean and southwest Pacific Ocean regions of the circum-Antarctic are reconstructed using sea-salt aerosol concentrations measured in the high resolution Law Dome (DSS) ice core from East Antarctica. The sea-salt aerosol concentration data, as sodium (Na), were measured at approximately monthly resolution spanning the past 700 years. Analyses of covariations between Na concentrations in Law Dome ice, and mean sea-level pressure (MSLP) and wind field data were conducted to define the mid-latitude and sub-Antarctic atmospheric circulation patterns associated with variations in Na delivery. High Na concentrations in Law Dome snow are associated with increased meridional aerosol transport from mid-latitude sources. The seasonal average Na concentration for early winter (May, June, July (MJJ)) is strongly correlated to the mid-latitude MSLP field in the South Indian and southwest Pacific Oceans, and southern Australian regions. In addition, the average MJJ Na concentrations display a strong association with the stationary Rossby wave number 3 circulation, and are anti-correlated to the Southern Annular Mode (SAM) index of climate variability: high (low) Na concentrations occurring during negative (positive) SAM phases. This observed relationship is used to derive a proxy record for early-winter MSLP anomalies and the SAM in the South Indian and southwest Pacific Ocean regions over the period 1300–1995 AD. The proxy SAM index from 1300 to 1995 AD shows pronounced decadal-scale variability throughout. The period after 1500 AD is marked by a tendency toward slower variations and a weakly-positive mean SAM (enhanced westerlies in the 50° to 65°S zone) compared to the early part of the record. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica ice core NOVA: The University of Newcastle Research Online (Australia) Antarctic East Antarctica Indian Law Dome ENVELOPE(112.833,112.833,-66.733,-66.733) Pacific |
institution |
Open Polar |
collection |
NOVA: The University of Newcastle Research Online (Australia) |
op_collection_id |
ftunivnewcastnsw |
language |
English |
topic |
South Indian Ocean Pacific Ocean Antarctica sea-salt aerosol concentration atmospheric circulation patterns |
spellingShingle |
South Indian Ocean Pacific Ocean Antarctica sea-salt aerosol concentration atmospheric circulation patterns Goodwin, I. D. van Ommen, T. D. Curran, M. A. J. Mayewski, P. A. Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
topic_facet |
South Indian Ocean Pacific Ocean Antarctica sea-salt aerosol concentration atmospheric circulation patterns |
description |
Mid-latitude winter atmospheric variability in the South Indian Ocean and southwest Pacific Ocean regions of the circum-Antarctic are reconstructed using sea-salt aerosol concentrations measured in the high resolution Law Dome (DSS) ice core from East Antarctica. The sea-salt aerosol concentration data, as sodium (Na), were measured at approximately monthly resolution spanning the past 700 years. Analyses of covariations between Na concentrations in Law Dome ice, and mean sea-level pressure (MSLP) and wind field data were conducted to define the mid-latitude and sub-Antarctic atmospheric circulation patterns associated with variations in Na delivery. High Na concentrations in Law Dome snow are associated with increased meridional aerosol transport from mid-latitude sources. The seasonal average Na concentration for early winter (May, June, July (MJJ)) is strongly correlated to the mid-latitude MSLP field in the South Indian and southwest Pacific Oceans, and southern Australian regions. In addition, the average MJJ Na concentrations display a strong association with the stationary Rossby wave number 3 circulation, and are anti-correlated to the Southern Annular Mode (SAM) index of climate variability: high (low) Na concentrations occurring during negative (positive) SAM phases. This observed relationship is used to derive a proxy record for early-winter MSLP anomalies and the SAM in the South Indian and southwest Pacific Ocean regions over the period 1300–1995 AD. The proxy SAM index from 1300 to 1995 AD shows pronounced decadal-scale variability throughout. The period after 1500 AD is marked by a tendency toward slower variations and a weakly-positive mean SAM (enhanced westerlies in the 50° to 65°S zone) compared to the early part of the record. |
format |
Article in Journal/Newspaper |
author |
Goodwin, I. D. van Ommen, T. D. Curran, M. A. J. Mayewski, P. A. |
author_facet |
Goodwin, I. D. van Ommen, T. D. Curran, M. A. J. Mayewski, P. A. |
author_sort |
Goodwin, I. D. |
title |
Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
title_short |
Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
title_full |
Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
title_fullStr |
Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
title_full_unstemmed |
Mid latitude Winter climate variability in the South Indian and southwest Pacific regions since 1300 AD |
title_sort |
mid latitude winter climate variability in the south indian and southwest pacific regions since 1300 ad |
publisher |
Springer |
publishDate |
2004 |
url |
http://hdl.handle.net/1959.13/26476 |
long_lat |
ENVELOPE(112.833,112.833,-66.733,-66.733) |
geographic |
Antarctic East Antarctica Indian Law Dome Pacific |
geographic_facet |
Antarctic East Antarctica Indian Law Dome Pacific |
genre |
Antarc* Antarctic Antarctica East Antarctica ice core |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica ice core |
op_relation |
Climate Dynamics Vol. 22, Issue 8, p. 783-794 10.1007/s00382-004-0403-3 |
_version_ |
1766261151676497920 |