Ice Age Temperatures and Geochemistry

Whether the last ice age was unusually chilly is more than merely historical curiosity. Such information is used to bench mark the computer models that are used to estimate future greenhouse warming. In his Perspective, Bard discusses recent efforts to use geochemical data to calculate past climate behavior. Data from noble gases in groundwater and trace elements in corals, for example, can indicate past sea surface temperatures. This can be compared with general circulation models, a comparison that shows good progress in modeling and also highlights where improvements can be made. According to the author, these advances have been made possible by the extensive exchanges of information between the data measurement and the modeling communities.

[1]  J. Duplessy,et al.  Evidence for changes in the North Atlantic Deep Water linked to meltwater surges during the Heinrich events , 1997 .

[2]  W. Broecker,et al.  Paleotemperatures in the Southwestern United States Derived from Noble Gases in Ground Water , 1992, Science.

[3]  P. Webster,et al.  Late Quaternary Ice Age Climates of Tropical Australasia: Interpretations and Reconstructions , 1978, Quaternary Research.

[4]  Richard G. Fairbanks,et al.  Tropical Temperature Variations Since 20,000 Years Ago: Modulating Interhemispheric Climate Change , 1994, Science.

[5]  R. Schneider,et al.  Late Quaternary surface circulation in the east equatorial South Atlantic: Evidence from Alkenone sea surface temperatures , 1995 .

[6]  W. Broecker,et al.  Evidence for massive discharges of icebergs into the North Atlantic ocean during the last glacial period , 1992, Nature.

[7]  Stefan Rahmstorf,et al.  Simulation of modern and glacial climates with a coupled global model of intermediate complexity , 1998, Nature.

[8]  E. Mosley‐Thompson,et al.  Late Glacial Stage and Holocene Tropical Ice Core Records from Huascar�n, Peru , 1995, Science.

[9]  Sandy P. Harrison,et al.  Monsoon changes for 6000 years ago: Results of 18 simulations from the Paleoclimate Modeling Intercomparison Project (PMIP) , 1999 .

[10]  E. Bard,et al.  TROPICAL SEA-SURFACE TEMPERATURES DURING THE LAST GLACIAL PERIOD : A VIEW BASED ON ALKENONES IN INDIAN OCEAN SEDIMENTS , 1998 .

[11]  S. Emerson,et al.  Foraminiferal magnesium in Globeriginoides sacculifer as a paleotemperature proxy , 1998 .

[12]  J. Vogel,et al.  Dissolved Gas Paleotemperatures and 18O Variations Derived from Groundwater Near Uitenhage, South Africa , 1986, Quaternary Research.

[13]  E. Bard,et al.  Interhemispheric synchrony of the last deglaciation inferred from alkenone palaeothermometry , 1997, Nature.

[14]  W. Broecker.  Oxygen Isotope Constraints on Surface Ocean Temperatures , 1986, Quaternary Research.

[15]  G. Bond,et al.  Iceberg Discharges into the North Atlantic on Millennial Time Scales During the Last Glaciation , 1995, Science.

[16]  T. Stocker,et al.  Rapid transitions of the ocean's deep circulation induced by changes in surface water fluxes , 1991, Nature.

[17]  Elsa Cortijo,et al.  Millennial‐scale iceberg discharges in the Irminger Basin during the Last Glacial Period: Relationship with the Heinrich events and environmental settings , 1998 .

[18]  K. Lambeck,et al.  Refining the eustatic sea-level curve since the Last Glacial Maximum using far- and intermediate-field sites , 1998 .

[19]  S. Drenkard,et al.  A tracer study of the Floridan Aquifer in southeastern Georgia: Implications for groundwater flow and paleoclimate , 1997 .

[20]  J. W. Beck,et al.  INTCAL98 Radiocarbon Age Calibration, 24,000–0 cal BP , 1998, Radiocarbon.