Evolution of Central Pacific Sea Surface Temperatures Over the Last 150 ka

Abstract:

Few records of tropical Pacific sea surface temperatures (SSTs) extend through the penultimate interglacial and glacial, Marine Isotope Stages 5 and 6. The records that do exist are largely located along the eastern and western margins, leaving uncertainties about the spatial patterns of SST change. As such, additional records from the central basin may improve our understanding of the tropical Pacific ocean-atmosphere response to greenhouse gas and orbital forcing on glacial timescales. Here we present new SST reconstructions over the last ~150,000 years from Mg/Ca in Globigerninoides ruber from cores collected along the Line Islands ridge (0-7 N, 155-162 W). Initial results indicate that the magnitude of SST change across Termination II is similar to that across Termination I at core site 37BB (7 N). In addition to our new data, we also compile the existing G. ruber Mg/Ca and oxygen isotope records throughout the tropics (20 N to 20 S) to explore the spatial and temporal patterns in surface temperature and oxygen isotope changes throughout the last glacial cycle.