@article {2541,
	title = {Climate-related response of dust flux to the central equatorial Pacific over the past 150 kyr},
	journal = {Earth and Planetary Science Letters},
	volume = {457},
	year = {2017},
	month = {Jan-01-2017},
	pages = {160 - 172},
	abstract = {High resolution paleoclimate records from low latitudes are critical for understanding the role of the tropics in transmitting and generating feedbacks for high-latitude climate change on glacial{\textendash}interglacial and millennial timescales. Here we present three new records of 230Thxs,0-normalized 232Th-derived dust fluxes from the central equatorial Pacific spanning the last 150 kyr at millennial-resolution. All three dust flux records share the {\textquotedblleft}sawtooth{\textquotedblright} pattern characteristic of glacial{\textendash}interglacial cycles in ice volume, confirming a coherent response to global climate forcing on long timescales. These records permit a detailed examination of millennial variability in tropical dust fluxes related to abrupt perturbations in oceanic and atmospheric circulation. Increases in dust flux in association with at least six of the longest Greenland stadials provide evidence that abrupt, high-latitude climate oscillations influenced the atmospheric aerosol load in the equatorial Pacific, with implications for both direct and indirect effects on the tropical energy balance. Our latitudinal transect of cores captures shifts in the position of the Intertropical Convergence Zone (ITCZ) in response to variations in the interhemispheric thermal gradient associated with cooling in Greenland and bipolar seesaw warming in Antarctica. These observations demonstrate that changes in the energy and hydrologic balance of the tropics were repeated features of the penultimate deglaciation, last glacial inception and last glacial cycle, and highlight the role of the tropical atmosphere as a dynamic and responsive component of Earth{\textquoteright}s climate system.},
	keywords = {abrupt climate change, dust, equatorial pacific, Intertropical Convergence Zone, stadial events},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2016.09.042},
	url = {https://doi.org/10.1016/j.epsl.2016.09.042},
	author = {Jacobel, A.W. and McManus, J.F. and Anderson, R.F. and Winckler, G.}
}
@article {2570,
	title = {Large deglacial shifts of the Pacific Intertropical Convergence Zone},
	journal = {Nature Communications},
	volume = {7},
	year = {2016},
	month = {Oct-01-2017},
	pages = {10449},
	abstract = {The position of the Intertropical Convergence Zone (ITCZ) is sensitive to changes in the balance of heat between the hemispheres which has fundamental implications for tropical hydrology and atmospheric circulation. Although the ITCZ is thought to experience the largest shifts in position during deglacial stadial events, the magnitude of shifts has proven difficult to reconstruct, in part because of a paucity of high-resolution records, particularly those including spatial components. Here we track the position of the ITCZ from 150 to 110 ka at three sites in the central equatorial Pacific at sub-millennial time resolution. Our results provide evidence of large, abrupt changes in tropical climate during the penultimate deglaciation, coincident with North Atlantic Heinrich Stadial 11 (\~{}136{\textendash}129 ka). We identify this event both as a Northern Hemisphere increase in aeolian dust and as a shift in the mean position of the ITCZ a minimum of 4{\textdegree} southwards at 160{\textdegree} W.},
	doi = {10.1038/ncomms10449},
	url = {http://www.nature.com/doifinder/10.1038/ncomms10449},
	author = {Jacobel, A. W. and McManus, J. F. and Anderson, R. F. and Winckler, G.}
}
@article {2542,
	title = {No iron fertilization in the equatorial Pacific Ocean during the last ice age},
	journal = {Nature},
	volume = {529},
	year = {2016},
	month = {Mar-01-2018},
	pages = {519 - 522},
	abstract = {The equatorial Pacific Ocean is one of the major high-nutrient, low-chlorophyll regions in the global ocean. In such regions, the consumption of the available macro-nutrients such as nitrate and phosphate is thought to be limited in part by the low abundance of the critical micro-nutrient iron1. Greater atmospheric dust deposition2 could have fertilized the equatorial Pacific with iron during the last ice age{\textemdash}the Last Glacial Period (LGP){\textemdash}but the effect of increased ice-age dust fluxes on primary productivity in the equatorial Pacific remains uncertain3, 4, 5, 6. Here we present meridional transects of dust (derived from the 232Th proxy), phytoplankton productivity (using opal, 231Pa/230Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound δ15N) from six cores in the central equatorial Pacific for the Holocene (0{\textendash}10,000 years ago) and the LGP (17,000{\textendash}27,000 years ago). We find that, although dust deposition in the central equatorial Pacific was two to three times greater in the LGP than in the Holocene, productivity was the same or lower, and the degree of nitrate consumption was the same. These biogeochemical findings suggest that the relatively greater ice-age dust fluxes were not large enough to provide substantial iron fertilization to the central equatorial Pacific. This may have been because the absolute rate of dust deposition in the LGP (although greater than the Holocene rate) was very low. The lower productivity coupled with unchanged nitrate consumption suggests that the subsurface major nutrient concentrations were lower in the central equatorial Pacific during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, we propose that the central equatorial Pacific data are consistent with more nutrient consumption in the Subantarctic Zone, possibly owing to iron fertilization as a result of higher absolute dust fluxes in this region7, 8. Thus, ice-age iron fertilization in the Subantarctic Zone would have ultimately worked to lower, not raise, equatorial Pacific productivity.},
	keywords = {Biogeochemistry, Palaeoceanography},
	issn = {0028-0836},
	doi = {10.1038/nature16453},
	url = {http://www.nature.com/doifinder/10.1038/nature16453},
	author = {Costa, K. M. and McManus, J. F. and Anderson, R. F. and Ren, H. and Sigman, D. M. and Winckler, G. and Fleisher, M. Q. and Marcantonio, F. and Ravelo, A. C.}
}
@article {482,
	title = {Modern CaCO3 preservation in equatorial Pacific sediments in the context of late-Pleistocene glacial cycles},
	journal = {Marine Chemistry},
	volume = {111},
	year = {2008},
	note = {id: 1936; PT: J; UT: WOS:000259418600004},
	pages = {30-46},
	abstract = {The CaCO3 content of marine sediments in many regions of the ocean has varied systematically with climate throughout the late-Pleistocene glacial cycles. Both biological productivity and carbonate preservation have been proposed to be the master variable regulating this variability. We have evaluated the preserved flux of CaCO3 in cores from the central equatorial Pacific Ocean (similar to 140 degrees W) using the Th-230-normalization technique. Neither barite fluxes nor Be-10/Th-230 ratios, both geochemical proxies for export production, correlate with CaCO3 fluxes, indicating that productivity is not the principal factor controlling CaCO3 accumulation in these sediments. Preserved fluxes of CaCO3 in central equatorial Pacific sediments correlate in time with the benchmark CaCO3 record from the Cape Basin (South Atlantic Ocean), supporting the view that changes in ocean chemistry (carbonate ion concentration) have controlled the pattern of CaCO3 preservation and accumulation at these sites. Modem CaCO3 preservation in equatorial Pacific sediments has dropped to levels nearly as low as those experienced at any time in the late Pleistocene. Similar changes occurred at the end of each of the late-Pleistocene interglacial periods, from which we infer that ocean carbonate chemistry has already undergone changes that are expected to precede the transition into the next ice age. However, during the late Pleistocene, the time interval between the decrease in CaCO3 preservation and the end of the interglacial has varied substantially from one interglacial to another (from similar to 2000 to similar to 15,000 years), so the late-Holocene decrease in CaCO3 preservation cannot be used to predict the end of the Holocene interglacial period. (C) 2007 Elsevier B.V. All rights reserved.},
	issn = {0304-4203},
	doi = {10.1016/j.marchem.2007.11.011},
	author = {Anderson, R. F. and Fleisher, M. Q. and Lao, Y. and Winckler, G.}
}
