Terrestrial chronologies from southern Greenland provide a detailed deglacial history of the Greenland Ice Sheet (GIS). The northern GIS margin history, however, is less established. Here we present surface exposure ages from moraines associated with two large outlet glaciers, Petermann and Humboldt, in the northwestern sector of the GIS. These...
The mass accumulation rates of sedimentary components (carbonate, organic carbon, opal, barite, reactive phosphate, iron, terrigenous minerals, etc.) are used in many paleoceanographic reconstructions to learn about temporal and spatial changes in surficial Earth processes including wind stress and direction, oceanic circulation, weathering rates, marine productivity and ecosystem structure, climate...
We constructed biogenic mass accumulation rate (MAR) time series for eastern Pacific core transects across the equator at ~105˚and ~85˚W and along the equator from 80˚to 140˚W. We used empirical orthogonal function (EOF) analysis to extract spatially coherent patterns of CaCO₃deposition for the last 150 kyr. EOF mode 1 (51%...
The sensitivity of the tropics to climate change, particularly the amplitude of glacial‐to‐interglacial changes in sea surface temperature (SST), is one of the great controversies in paleoclimatology. Here we reassess faunal estimates of ice age SSTs, focusing on the problem of no‐analog planktonic foraminiferal assemblages in the equatorial oceans that...
Benthic foraminiferal δ¹³C data from site 502 in the Caribbean Sea (sill depth 1800 m) indicate that throughout the past 2.6 m.y., glacial δ¹³C values in the middepth Atlantic were higher during glaciations than interglaciations. This is interpreted as indicating a greater proportion of Upper North Atlantic Deep Water (UNADW)...
We evaluate the reliability of statistical estimates of sea surface temperature (SST) derived from planktonic foraminiferal faunas using the modern analog method and the Imbrie‐Kipp method. Global core top faunas provide a calibration data set, while modern sediment trap faunas are used for validation. Linear regression of core top predicted...
Sea surface temperature (SST) and salinity of the Western Pacific Warm Pool (WPWP) reflect global climate effects such as the El Niño–Southern Oscillation phenomenon. However, reconstructions of past changes in the WPWP from the geologic record vary depending on the specific proxy record used. Here we develop a multiproxy record...
More than 7 km of long and relatively continuous sediment sequences
from 11 sites in the southeast and equatorial Pacific were recovered
during Leg 202 for the study of the Earth’s climate and biogeochemical
systems on scales that range from tectonic (millions of
years) to orbital (tens to hundreds of...
Ocean Drilling Program (ODP) Leg 138 was designed to study the late Neogene paleoceanography of the equatorial Pacific Ocean at time scales of thousands to millions of years. Crucial to this objective was the acquisition of continuous, high-resolution sedimentary records. It is well known that between successive advanced piston corer...
Sediment spectral reflectance measurements were generated aboard the JOIDES Resolution during Ocean Drilling Program Leg 162 shipboard operations. The large size of the raw data set (over 1.3 gigabytes) and limited computer hard disk storage space precluded detailed analysis of the data at sea, although broad band averages were used...