Glacial‐interglacial dynamics of the eastern equatorial Pacific cold tongue‐Intertropical Convergence Zone system reconstructed from oxygen isotope records

record mean late Holocene (LH)-Last Glacial Maximum (LGM) d 18 O amplitudes ranging between 1.0 and 1.3%. We estimate that mean sea surface temperatures (SST) in this region during the LGM were on average 1.5 ± 0.5� C lower than the LH. Larger d 18 O amplitudes are observed in sites north of the equator, indicating a spatial pattern of reduced meridional SST gradient across the equator during the LGM. This result is supported by comparison of Mg/Ca SST reconstructions from two sites straddling the equator. We interpret the reduction of this gradient during the LGM as evidence for a less intense cold tongue-Intertropical Convergence Zone (ITCZ) frontal system, a more southerly position of the ITCZ, and weaker southeast equatorial trades in the EEP. INDEXTERMS: 1620 Global Change: Climate dynamics (3309); 3339 Meteorology and Atmospheric Dynamics: Ocean/atmosphere interactions (0312, 4504); 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology; 4231 Oceanography: General: Equatorial oceanography; 4267 Oceanography: General: Paleoceanography; KEYWORDS: cold tongue, ITCZ, oxygen isotopes, tropical Pacific

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