Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records
The East Asian Monsoon (EAM) exhibits a significant variability on timescales ranging from tectonic to centennial as inferred from loess, speleothem and marine records. However, the relative contributions and plausible driving forces of the monsoon variability at different timescales remain controve...
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ftdoajarticles:oai:doaj.org/article:58fb79f94bbf473ab1adb5ee0095101b 2023-05-15T17:35:22+02:00 Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records Y. Li N. Su L. Liang L. Ma Y. Yan Y. Sun 2015-08-01T00:00:00Z https://doi.org/10.5194/cp-11-1067-2015 https://doaj.org/article/58fb79f94bbf473ab1adb5ee0095101b EN eng Copernicus Publications http://www.clim-past.net/11/1067/2015/cp-11-1067-2015.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 1814-9324 1814-9332 doi:10.5194/cp-11-1067-2015 https://doaj.org/article/58fb79f94bbf473ab1adb5ee0095101b Climate of the Past, Vol 11, Iss 8, Pp 1067-1075 (2015) Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 article 2015 ftdoajarticles https://doi.org/10.5194/cp-11-1067-2015 2022-12-31T02:54:53Z The East Asian Monsoon (EAM) exhibits a significant variability on timescales ranging from tectonic to centennial as inferred from loess, speleothem and marine records. However, the relative contributions and plausible driving forces of the monsoon variability at different timescales remain controversial. Here, we spectrally explore time series of loess grain size and speleothem δ 18 O records and decompose the two proxies into intrinsic components using the empirical mode decomposition method. Spectral results of these two proxies display clear glacial and orbital periodicities corresponding to ice volume and solar cycles, and evident millennial signals which are in pace with Heinrich rhythm and Dansgaard–Oeschger (DO) cycles. Five intrinsic components are parsed out from loess grain size and six intrinsic components from speleothem δ 18 O records. Combined signals are correlated further with possible driving factors including the ice volume, insolation and North Atlantic cooling from a linear point of view. The relative contributions of components differ significantly between loess grain size and speleothem δ 18 O records. Coexistence of glacial and orbital components in the loess grain size implies that both ice volume and insolation have distinctive impacts on the winter monsoon variability, in contrast to the predominant precessional impact on the speleothem δ 18 O variability. Moreover, the millennial components are evident in loess grain size and speleothem δ 18 O records with variances of 13 and 17 %, respectively. A comparison of the millennial-scale signals of these two proxies reveals that abrupt changes in the winter and summer monsoons over the last 260 kyr share common features and similar driving forces linked to high-latitude Northern Hemisphere climate. Article in Journal/Newspaper North Atlantic Directory of Open Access Journals: DOAJ Articles Climate of the Past 11 8 1067 1075 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
topic |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
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Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 Y. Li N. Su L. Liang L. Ma Y. Yan Y. Sun Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
topic_facet |
Environmental pollution TD172-193.5 Environmental protection TD169-171.8 Environmental sciences GE1-350 |
description |
The East Asian Monsoon (EAM) exhibits a significant variability on timescales ranging from tectonic to centennial as inferred from loess, speleothem and marine records. However, the relative contributions and plausible driving forces of the monsoon variability at different timescales remain controversial. Here, we spectrally explore time series of loess grain size and speleothem δ 18 O records and decompose the two proxies into intrinsic components using the empirical mode decomposition method. Spectral results of these two proxies display clear glacial and orbital periodicities corresponding to ice volume and solar cycles, and evident millennial signals which are in pace with Heinrich rhythm and Dansgaard–Oeschger (DO) cycles. Five intrinsic components are parsed out from loess grain size and six intrinsic components from speleothem δ 18 O records. Combined signals are correlated further with possible driving factors including the ice volume, insolation and North Atlantic cooling from a linear point of view. The relative contributions of components differ significantly between loess grain size and speleothem δ 18 O records. Coexistence of glacial and orbital components in the loess grain size implies that both ice volume and insolation have distinctive impacts on the winter monsoon variability, in contrast to the predominant precessional impact on the speleothem δ 18 O variability. Moreover, the millennial components are evident in loess grain size and speleothem δ 18 O records with variances of 13 and 17 %, respectively. A comparison of the millennial-scale signals of these two proxies reveals that abrupt changes in the winter and summer monsoons over the last 260 kyr share common features and similar driving forces linked to high-latitude Northern Hemisphere climate. |
format |
Article in Journal/Newspaper |
author |
Y. Li N. Su L. Liang L. Ma Y. Yan Y. Sun |
author_facet |
Y. Li N. Su L. Liang L. Ma Y. Yan Y. Sun |
author_sort |
Y. Li |
title |
Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
title_short |
Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
title_full |
Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
title_fullStr |
Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
title_full_unstemmed |
Multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in Chinese loess and speleothem records |
title_sort |
multiscale monsoon variability during the last two climatic cycles revealed by spectral signals in chinese loess and speleothem records |
publisher |
Copernicus Publications |
publishDate |
2015 |
url |
https://doi.org/10.5194/cp-11-1067-2015 https://doaj.org/article/58fb79f94bbf473ab1adb5ee0095101b |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Climate of the Past, Vol 11, Iss 8, Pp 1067-1075 (2015) |
op_relation |
http://www.clim-past.net/11/1067/2015/cp-11-1067-2015.pdf https://doaj.org/toc/1814-9324 https://doaj.org/toc/1814-9332 1814-9324 1814-9332 doi:10.5194/cp-11-1067-2015 https://doaj.org/article/58fb79f94bbf473ab1adb5ee0095101b |
op_doi |
https://doi.org/10.5194/cp-11-1067-2015 |
container_title |
Climate of the Past |
container_volume |
11 |
container_issue |
8 |
container_start_page |
1067 |
op_container_end_page |
1075 |
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1766134516093550592 |