(Table 1) Alkenone concentration, UK'37 index and derived sea surface temperatures for ODP Site 167-1020, supplement to: Kreitz, Scott F; Herbert, Timothy D; Schuffert, Jeffrey D (2000): Alkenone paleothermometry and orbital-scale changes in sea-surface temperature at Site 1020 northern California margin. In: Lyle, M; Koizumi, I; Richter, C; Moore, TC Jr (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 167, 1-9


Uk'37 sea-surface temperature (SST) estimates obtained at ~2.5-k.y. resolution from Ocean Drilling Program Site 1020 show glacial-interglacial cyclicity with an amplitude of 7°-10°C over the last 780 k.y. This record shows a similar pattern of variability to another alkenone-based SST record obtained previously from the Santa Barbara Basin. Both records show that oxygen isotope Stage (OIS) 5.5 was warmer by ~3°C relative to the present and that glacial Uk'37 temperatures warm in advance of deglaciation, as inferred from benthic d18O records. The alkenone-based SST record at Site 1020 is longer than previously published work along the California margin. We show that warmer than present interglacial stages have occurred frequently during the last 800 k.y. Alkenone concentrations, a proxy for coccolithophorid productivity, indicate that sedimentary marine organic carbon content has also varied significantly over this interval, with higher contents during interglacial periods. A baseline shift to warmer SST and greater alkenone content occurs before OIS 13.We compare our results with those from previous multiproxy studies in this region and conclude that SST has increased by ~5°C since the last glacial period (21 ka). Our data show that maximum alkenone SSTs occur simultaneously with minimum ice volume at Site 1020, which is consistent with data from farther south along the margin. The presence of sea ice in the glacial northeast Pacific, the extent of which is inferred from locations of ice-rafted debris, provides further support for our notion of cold surface water within the northern California Current system, averaging 7°-8°C cooler during peak glacial conditions. The cooling of surface water during glacial stages most likely did not result from enhanced upwelling because alkenone concentrations and terrestrial redwood pollen assemblages are consistently lower during glacial periods. Sediment depth is given in mcd.

DOI https://doi.org/10.1594/PANGAEA.793496
Related Identifier https://doi.org/10.2973/odp.proc.sr.167.213.2000
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.793496
Creator Kreitz, Scott F; Herbert, Timothy D; Schuffert, Jeffrey D
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2000
Rights Creative Commons Attribution 3.0 Unported
OpenAccess true
Language English
Resource Type Supplementary Dataset
Format text/tab-separated-values
Size 1528 data points
Discipline Earth System Research
Spatial Coverage (-126.434 LON, 41.008 LAT); North Pacific Ocean
Temporal Coverage Begin 1996-06-08T00:00:00Z
Temporal Coverage End 1996-06-12T00:00:00Z