Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough
Abstract We reviewed three sea surface temperature (SST) proxies in the Okinawa Trough (OT): alkenones, planktonic foraminiferal Mg/Ca, and planktonic foraminiferal assemblages. The seasonal and vertical distribution patterns of each proxy-related organism in the water column were reviewed to confir...
Main Authors: | , , |
---|---|
Format: | Review |
Language: | English |
Published: |
BioMed Central Ltd.
2015
|
Subjects: | |
Online Access: | http://www.progearthplanetsci.com/content/2/1/43 |
id |
ftbiomed:oai:biomedcentral.com:s40645-015-0074-1 |
---|---|
record_format |
openpolar |
spelling |
ftbiomed:oai:biomedcentral.com:s40645-015-0074-1 2023-05-15T17:37:08+02:00 Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough Kim, Ryoung Lee, Kyung Bae, Si 2015-12-01 http://www.progearthplanetsci.com/content/2/1/43 en eng BioMed Central Ltd. http://www.progearthplanetsci.com/content/2/1/43 Copyright 2015 Kim et al. Sea surface temperature Okinawa Trough Alkenone Planktonic foraminiferal Mg/Ca ratio Planktonic foraminiferal assemblages Review 2015 ftbiomed 2015-12-06T01:11:01Z Abstract We reviewed three sea surface temperature (SST) proxies in the Okinawa Trough (OT): alkenones, planktonic foraminiferal Mg/Ca, and planktonic foraminiferal assemblages. The seasonal and vertical distribution patterns of each proxy-related organism in the water column were reviewed to confirm the applicability of each proxy. In addition, current SSTs (Japan Oceanographic Data Center dataset from 1906 to 2003) were compared with core-top sediment temperatures reconstructed using the proxies. Temperatures calculated using the alkenone unsaturation index represent annual mean SSTs, and temperatures calculated using Mg/Ca of Globigerinoides ruber capture summer to autumn (June–November) SSTs. Core-top August SSTs calculated from planktonic foraminiferal assemblages corresponded well with the observed SSTs, but core-top February temperatures were ~3.6 °C warmer than the observed SSTs. SST proxy estimates from marine sediments dating back to the late Holocene (0–3 cal ky BP) and the last glacial maximum (18–21 cal ky BP) were compared. Comparisons between proxy SST estimates show that foraminiferal assemblage-based August SSTs were the warmest. Alkenone-based temperature estimates were lower than Mg/Ca-based temperature estimates, probably because the alkenone-based temperature represents the annual mean temperature, whereas the Mg/Ca-based temperature represents the summer–autumn mean temperature. February assemblage SSTs seem to be greatly affected by the statistical technique and/or database used. These results suggest that seasonality should be considered in past SST reconstruction using alkenone and Mg/Ca in the OT. The planktonic foraminiferal assemblage technique does not appear to be promising with respect to accurately reconstructing past SSTs (especially winter) in the OT. Habitat depth may not be an issue because both alkenone producers and G. ruber live at the upper surface mixed layer in the area. Glacial–interglacial changes in the surface hydrography of the OT reconstructed based on the SST and salinity proxies were also reviewed here. The surface hydrography of the OT has been influenced by changes in the Kuroshio Current and the East Asian monsoon system during the late Quaternary. Comparisons of the hydrography records from the OT with records of stalagmites in China, the Tropical Pacific, and the North Atlantic show that there is a teleconnection between them. Review North Atlantic BioMed Central Pacific |
institution |
Open Polar |
collection |
BioMed Central |
op_collection_id |
ftbiomed |
language |
English |
topic |
Sea surface temperature Okinawa Trough Alkenone Planktonic foraminiferal Mg/Ca ratio Planktonic foraminiferal assemblages |
spellingShingle |
Sea surface temperature Okinawa Trough Alkenone Planktonic foraminiferal Mg/Ca ratio Planktonic foraminiferal assemblages Kim, Ryoung Lee, Kyung Bae, Si Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
topic_facet |
Sea surface temperature Okinawa Trough Alkenone Planktonic foraminiferal Mg/Ca ratio Planktonic foraminiferal assemblages |
description |
Abstract We reviewed three sea surface temperature (SST) proxies in the Okinawa Trough (OT): alkenones, planktonic foraminiferal Mg/Ca, and planktonic foraminiferal assemblages. The seasonal and vertical distribution patterns of each proxy-related organism in the water column were reviewed to confirm the applicability of each proxy. In addition, current SSTs (Japan Oceanographic Data Center dataset from 1906 to 2003) were compared with core-top sediment temperatures reconstructed using the proxies. Temperatures calculated using the alkenone unsaturation index represent annual mean SSTs, and temperatures calculated using Mg/Ca of Globigerinoides ruber capture summer to autumn (June–November) SSTs. Core-top August SSTs calculated from planktonic foraminiferal assemblages corresponded well with the observed SSTs, but core-top February temperatures were ~3.6 °C warmer than the observed SSTs. SST proxy estimates from marine sediments dating back to the late Holocene (0–3 cal ky BP) and the last glacial maximum (18–21 cal ky BP) were compared. Comparisons between proxy SST estimates show that foraminiferal assemblage-based August SSTs were the warmest. Alkenone-based temperature estimates were lower than Mg/Ca-based temperature estimates, probably because the alkenone-based temperature represents the annual mean temperature, whereas the Mg/Ca-based temperature represents the summer–autumn mean temperature. February assemblage SSTs seem to be greatly affected by the statistical technique and/or database used. These results suggest that seasonality should be considered in past SST reconstruction using alkenone and Mg/Ca in the OT. The planktonic foraminiferal assemblage technique does not appear to be promising with respect to accurately reconstructing past SSTs (especially winter) in the OT. Habitat depth may not be an issue because both alkenone producers and G. ruber live at the upper surface mixed layer in the area. Glacial–interglacial changes in the surface hydrography of the OT reconstructed based on the SST and salinity proxies were also reviewed here. The surface hydrography of the OT has been influenced by changes in the Kuroshio Current and the East Asian monsoon system during the late Quaternary. Comparisons of the hydrography records from the OT with records of stalagmites in China, the Tropical Pacific, and the North Atlantic show that there is a teleconnection between them. |
format |
Review |
author |
Kim, Ryoung Lee, Kyung Bae, Si |
author_facet |
Kim, Ryoung Lee, Kyung Bae, Si |
author_sort |
Kim, Ryoung |
title |
Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
title_short |
Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
title_full |
Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
title_fullStr |
Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
title_full_unstemmed |
Sea surface temperature proxies (alkenones, foraminiferal Mg/Ca, and planktonic foraminiferal assemblage) and their implications in the Okinawa Trough |
title_sort |
sea surface temperature proxies (alkenones, foraminiferal mg/ca, and planktonic foraminiferal assemblage) and their implications in the okinawa trough |
publisher |
BioMed Central Ltd. |
publishDate |
2015 |
url |
http://www.progearthplanetsci.com/content/2/1/43 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
http://www.progearthplanetsci.com/content/2/1/43 |
op_rights |
Copyright 2015 Kim et al. |
_version_ |
1766136895281037312 |