Data/hora: 15/06/2024 14:14:50

Provedor de dados: 	5	
País: 	France	
Título: 	Reduced-dimension reconstruction of the equatorial Pacific SST and zonal wind fields over the past 10,000years using Mg/Ca and alkenone records	
Autores: 	Gill, Emily C.; Rajagopalan, Balaji; Molnar, Peter; Marchitto, Thomas M.	
Data: 	2016-07	
Ano: 	2016	
Palavras-chave: 	Sea surface temperatures; ENSO; Holocene; Multiproxy field reconstruction; Equatorial Pacific; Reduced-dimension.	
Resumo: 	We develop a multiproxy, reduced-dimension methodology to blend magnesium-calcium (Mg/Ca) and alkenone (U 37k) paleo sea surface temperature (SST) records from the eastern and western equatorial Pacific, to recreate snapshots of full field SSTs and zonal winds from 10 to 2ka B.P. in 2000year increments. Single-proxy reconstructions (Mg/Ca only versus U 37K only) reveal differences in the timing and duration of maximum cooling across the east-central equatorial Pacific. The largest zonal temperature differences (average west Pacific SST minus average east Pacific SST) occur at 6ka B.P. for the Mg/Ca-only reconstruction (0.61 degrees C) and at 10 and 4ka for the U 37K-only reconstruction (0.55 degrees C and 0.47 degrees C, respectively). Disagreements between SST trends suggested by each proxy call for methods that can resolve the common patterns between each and have motivated the work presented in this study. In combining inferences from these proxies, we treat both Mg/Ca and U 37K reconstructions of SST as annual average values, but we recognize that they may be sensitive to different seasons. In the multiproxy reconstruction, the zonal SST difference is largest at 10ka (0.26 degrees C), with coldest SST anomalies of approximate to-0.9 degrees C in the eastern equatorial Pacific and concurrent easterly maximum zonal wind anomalies of 7ms(-1) throughout the central Pacific. From 10 to 2ka, the entire equatorial Pacific warms, but at a faster rate in the east than the west, and the average central Pacific easterly winds weaken gradually to approximately 2ms(-1). These patterns are broadly consistent with previous inferences of reduced El Nino-Southern Oscillation variability associated with a La Nina-like state during the early to middle Holocene.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	https://archimer.ifremer.fr/doc/00421/53232/54785.pdf

DOI:10.1002/2016PA002948

https://archimer.ifremer.fr/doc/00421/53232/	
Editor: 	Amer Geophysical Union	
Formato: 	application/pdf	
Fonte: 	Paleoceanography (0883-8305) (Amer Geophysical Union), 2016-07 , Vol. 31 , N. 7 , P. 928-952	
Fonte: 	2016. American Geophysical Union. All Rights Reserved.

info:eu-repo/semantics/openAccess

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