Planktonic foraminifera abundances and isotopes of Late Quaternary sediments off New Zealand ...

• Main Authors: Weaver, Philip PE, Carter, Lionel, Neil, Helen L
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1998
• Subjects: Planktonic foraminifera
• Online Access: https://dx.doi.org/10.1594/pangaea.866903; https://doi.pangaea.de/10.1594/PANGAEA.866903

A series of cores from east of New Zealand have been examined to determine the paleoceanographic history of the late Quaternary in the SW Pacific using planktonic foraminiferal data. Distinct shifts of species can be seen between glacial and interglacial times especially south of Chatham Rise east of South Island. Foraminiferal fragmentation ratios and benthic/planktonic foraminiferal ratios both show increased dissolution during glacials, especially isotope stage 2 to the south of Chatham Rise. The present-day Subtropical Convergence appears to be tied to the Chatham Rise at 44°S, but during glacial times this rise separated cold water to the south from much warmer water to the north, with an associated strong thermal gradient across the rise. We estimate that this gradient could have presented as much as an 8°C temperature change across 4° of latitude during the maximum of the last ice age. There is only weak evidence of the Younger Dryas cool event, but there is a clear climatic optimum between 8 and 6.4 ... : Supplement to: Weaver, Philip PE; Carter, Lionel; Neil, Helen L (1998): Response of surface water masses and circulation to Late Quaternary climate change east of New Zealand. Paleoceanography, 13(1), 70-83 ...