@article {2079, title = {Decadal timescale shift in the 14C record of a central equatorial Pacific coral}, journal = {Radiocarbon}, volume = {45}, year = {2003}, note = {id: 1130}, month = {2003}, pages = {91-99}, author = {Grottoli, A. G. and Gille, S. T. and Druffel, E. R. M. and Dunbar, R. B.} } @conference {1768, title = {Radiocarbon in a Fanning Island coral: Inter-decadal variability in waters upwelling in the central equatorial Pacific from 1922-1955}, booktitle = {ALSO/AGU Ocean Sciences Meeting}, year = {2002}, note = {id: 658}, month = {2002}, address = {Honolulu, HI}, author = {Grottoli, A. G. and Gille, S. T. and Druffel, E. R. M. and Dunbar, R. B.} } @article {2154, title = {Carbon Isotope Ratios of Organic Compound Fractions Separated From Sinking Particulate Organic Matter at a Deep Sea Station in the Northeast Pacific}, journal = {EOS}, year = {2001}, note = {id: 256}, month = {2001}, author = {Druffel, E. R. and Grottoli, A. G. and Gille, S. T. and Dunbar, R. B.} } @article {340, title = {The history of South American tropical precipitation for the past 25,000 years}, journal = {Science}, volume = {291}, year = {2001}, note = {id: 369; Baker, P A Seltzer, G O Fritz, S C Dunbar, R B Grove, M J Tapia, P M Cross, S L Rowe, H D Broda, J P New York, N.Y. Science. 2001 Jan 26;291(5504):640-3.}, pages = {640-3}, abstract = {Long sediment cores recovered from the deep portions of Lake Titicaca are used to reconstruct the precipitation history of tropical South America for the past 25,000 years. Lake Titicaca was a deep, fresh, and continuously overflowing lake during the last glacial stage, from before 25,000 to 15,000 calibrated years before the present (cal yr B.P.), signifying that during the last glacial maximum (LGM), the Altiplano of Bolivia and Peru and much of the Amazon basin were wetter than today. The LGM in this part of the Andes is dated at 21,000 cal yr B.P., approximately coincident with the global LGM. Maximum aridity and lowest lake level occurred in the early and middle Holocene (8000 to 5500 cal yr B.P.) during a time of low summer insolation. Today, rising levels of Lake Titicaca and wet conditions in Amazonia are correlated with anomalously cold sea-surface temperatures in the northern equatorial Atlantic. Likewise, during the deglacial and Holocene periods, there were several millennial-scale wet phases on the Altiplano and in Amazonia that coincided with anomalously cold periods in the equatorial and high-latitude North Atlantic, such as the Younger Dryas.}, issn = {0036-8075 (Print) 0036-8075 (Linking)}, doi = {10.1126/science.291.5504.640}, author = {Baker, P. A. and Seltzer, G. O. and Fritz, S. C. and Dunbar, R. B. and Grove, M. J. and Tapia, P. M. and Cross, S. L. and Rowe, H. D. and Broda, J. P.} } @article {870, title = {Late quaternary climate and hydrology of tropical South America inferred from an isotopic and chemical model of Lake Titicaca, Bolivia and Peru}, journal = {Quaternary Research}, volume = {56}, year = {2001}, note = {452lzTimes Cited:50Cited References Count:46}, month = {Jul}, pages = {1-9}, abstract = {A simple mass balance model provides insight into the hydrologic, isotopic, and chemical responses of Lake Titicaca to past climatic changes. Latest Pleistocene climate of the Altiplano is assumed to have been 20\% wetter and 5 degreesC colder than today, based on previous modeling. Our simulation of lacustrine change since 15,000 cal yr B.P. is forced by these modeled climate changes. The latest Pleistocene Lake Titicaca was deep, fresh, and overflowing. The latest Pleistocene riverine discharge from the lake was about 8 times greater than the modern average, sufficient to allow the expansion of the great paleolake Tauca on the central Altiplano. The lake delta O-18 value averaged about -13 parts per thousand SMOW (the modern value is about -4.2 parts per thousand). The early Holocene decrease in precipitation caused Lake Titicaca to fall below its outlet and contributed to a rapid desiccation of paleolake Tauca. Continued evaporation caused the 100-m drop in lake level, but only a slight(1-2 parts per thousand) increase (relative to modern) in delta O-18 Of early Holocene lake waters. This Holocene lowstand level of nearly 100 m was most likely produced by a precipitation decrease, relative to modern, of about 40\%, The lake was saline as recently as 2000 cal yr B.P. The timing of these hydrologic changes is in general agreement with calculated changes of insolation forcing of the South American summer monsoon, (C) 2001 University of Washington.}, issn = {0033-5894}, doi = {10.1006/qres.2001.2244}, author = {Cross, S. L. and Baker, P. A. and Seltzer, G. O. and Fritz, S. C. and Dunbar, R. B.} } @article {2146, title = {Radiocarbon in a Fanning Island Coral: Inter-decadal Variability in Waters Upwelling in the Central Equatorial Pacific from 1922 - 1955}, journal = {EOS}, year = {2001}, note = {id: 1399}, month = {2001}, author = {Grottoli, A. G. and Gille, S. T. and Druffel, E. R. M. and Dunbar, R. B.} } @article {2196, title = {Identification of Seasonal-to-Decadal Timescale Variations in the Zonal Currents of the Central Equatorial Pacific Prior to 1955 Using A14C in Coral}, journal = {EOS}, volume = {81}, year = {2000}, note = {id: 254}, month = {2000}, abstract = {F767}, author = {Grottoli, A. G. and Druffel, E. R. M. and Gille, S. T. and Dunbar, R. B.} } @conference {1651, title = {Identification of seasonal-to-decadal timescale variations in the zonal currents of the central equatorial Pacific}, booktitle = {International Coral Reef Symposium}, year = {2000}, note = {id: 1401}, month = {2000}, address = {Bali}, author = {Grottoli, A. G. and Druffel, E. R. M. and Gille, S. T. and Dunbar, R. B.} }