Merging late Holocene molecular organic and foraminiferal-based geochemical records of sea surface temperature in the Gulf of Mexico
Richey, Julie N.
Hollander, David J.
Flower, Benjamin P.
Eglinton, Timothy I.
MetadataShow full item record
A molecular organic geochemical proxy (TEX86) for sea surface temperature (SST) is compared with a foraminifera-based SST proxy (Mg/Ca) in a decadal-resolution marine sedimentary record spanning the last 1000 years from the Gulf of Mexico. We assess the relative strengths of the organic and inorganic paleoceanographic techniques for reconstructing high-resolution SST variability during recent climate events, including the Little Ice Age (LIA) and the Medieval Warm Period (MWP). SST estimates based on the molecular organic proxy TEX86 show a similar magnitude and pattern of SST variability to foraminiferal Mg/Ca-SST estimates but with some important differences. For instance, both proxies show a cooling (1°C–2°C) of Gulf of Mexico SSTs during the LIA. During the MWP, however, Mg/Ca-SSTs are similar to near-modern SSTs, while TEX86 indicates SSTs that were cooler than modern. Using the respective SST calibrations for each proxy results in TEX86-SST estimates that are 2°C–4°C warmer than Mg/Ca-SST throughout the 1000 year record. We interpret the TEX86-SST as a summer-weighted SST signal from the upper mixed layer, whereas the Mg/Ca-SST better reflects the mean annual SST. Downcore differences in the SST estimates between the two proxies (ΔT = TEX86 − Mg/Ca) are interpreted in the context of varying seasonality and/or changing water column temperature gradients.
Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 26 (2011): PA1209, doi:10.1029/2010PA002000.
Showing items related by title, author, creator and subject.
Exploring typhoon variability over the mid-to-late Holocene : evidence of extreme coastal flooding from Kamikoshiki, Japan Woodruff, Jonathan D.; Donnelly, Jeffrey P.; Okusu, Akiko (2009-01)Sediment cores from two coastal lakes located on the island of Kamikoshiki in southwestern Japan (Lake Namakoike and Lake Kaiike) provide evidence for the response of a backbarrier beach system to episodic coastal ...
Compound-specific radiocarbon dating of the varved Holocene sedimentary record of Saanich Inlet, Canada Smittenberg, R. H.; Hopmans, Ellen C.; Schouten, Stefan; Hayes, John M.; Eglinton, Timothy I.; Sinninghe Damste, Jaap S. (American Geophysical Union, 2004-05-01)The radiocarbon contents of various biomarkers extracted from the varve-counted sediments of Saanich Inlet, Canada, were determined to assess their applicability for dating purposes. Calibrated ages obtained from the marine ...
Abrupt changes of temperature and water chemistry in the late Pleistocene and early Holocene Black Sea Bahr, Andre; Lamy, Frank; Arz, Helge W.; Major, Candace O.; Kwiecien, Olga; Wefer, Gerold (American Geophysical Union, 2008-01-12)New Mg/Ca, Sr/Ca, and published stable oxygen isotope and 87Sr/86Sr data obtained on ostracods from gravity cores located on the northwestern Black Sea slope were used to infer changes in the Black Sea hydrology and water ...