Brief description
In recent years the term 'enhanced greenhouse effect' has become well known in modern society and yet aspects of this possible 'future climate' are poorly understood. The characteristics of the geological record provide a basis to understand this possible future climate through the examination of alternating glacial (cold) and interglacial (warm) stages. Understanding the variability of sea-surface temperature and biological processes in the water column provides insight into general circulation of present and paleo-ocean currents. From core MD032607 the annual mean SST (Tmean) indicates a temperature range of 9oC±0.84oC between Marine Isotope Stage (MIS) 6 to MIS 5, representing the largest sea surface temperature (SST) transition from a glacial to interglacial. The results also suggest that there is more stratification in the water column during interglacial periods as opposed to glacials. Conversely, temperatures gradients are reduced during the Last Glacial Maximum (LGM) and MIS 6 suggesting a well mixed homogenised mixed layer.Lineage
Maintenance and Update Frequency: notPlanned
Statement: Sea-surface temperatures (SST) were estimated from planktonic foraminifera assemblage data. The most precise variable of SST is mean annual temperature, followed by Tmax, then Tmin. All variables have a root mean squared error of prediction of less than 1 degree C. Most of the SST estimates are reasonably precise, given that the samples have good analogues in the AUSMAT-F4 database. Typically, the glacial periods are less precise than the interglacials. Time periods with reduced quality of SST estimates are ~66k BP and 132-144k BP.
Parameters: Age of core (yrs BP), mean water temperature (oC), maximum water temperature (oC), minimum water temperature (oC), depth of mixed layer (m), temperature at 50m, 100m and 150m (oC).
Statement: Sea-surface temperatures (SST) were estimated from planktonic foraminifera assemblage data using the modern analogue technique (MAT), in conjunction with the AUSMAT-F4 database. Each SST estimate was calculated as the mean of the best 10 analogues from the global database.
Notes
CreditThe Australian National University (ANU)
Credit
Funded by The National Oceans Office (NOO)
Funded by The National Oceans Office (NOO)
Credit
Funded by The Australian Research Council (ARC)
Funded by The Australian Research Council (ARC)
Credit
Funded by The French Polar Institute
Funded by The French Polar Institute
Credit
Funded by The Australian Insitute of Nuclear Science and Engineering (AINSE)
Funded by The Australian Insitute of Nuclear Science and Engineering (AINSE)
Credit
Funded by The Murray Darling Basin Commission
Funded by The Murray Darling Basin Commission
Purpose
To investigate the dynamics of the Leeuwin Current. The hope was to determine synchronity between different cores and to indicate whether the Leeuwin Current was absent or reduced during glacial periods and enhanced or unchanged during interglacial periods.
To investigate the dynamics of the Leeuwin Current. The hope was to determine synchronity between different cores and to indicate whether the Leeuwin Current was absent or reduced during glacial periods and enhanced or unchanged during interglacial periods.
Issued: 22 03 2007
Data time period: 2003-01-01 to 2003-01-01
text: westlimit=137; southlimit=-40; eastlimit=137.5; northlimit=-39.5
text: uplimit=2034; downlimit=2034
Subjects
EARTH SCIENCE |
OCEAN TEMPERATURE |
OCEANS |
Water Temperature |
age_of_core |
depth |
oceans |
sea_surface_temperature |
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Other Information
(ANU_Spooner_MD032607_4_data.xls)
global : 1bca5f00-07fd-11dc-92a7-00188b4c0af8
Identifiers
- global : c22219c0-07fc-11dc-92a7-00188b4c0af8
