Quaternary climate change

In modem sediments particular assemblages of species are characteristic of particular environmental conditions. Therefore it is possible to use species assemblages in ancient sediments to infer past sea-surface temperatures and other variables, and these techniques provide a wealth 

The two most common isotopes of oxygen are and 0, and the two natural isotopes of hydrogen are and or D (deuterium). If a sample of carbonate contains Cis moles of and Ci6 moles of then define the heavy light ratio as Ris = Cia/Cie- Similarly, natural water molecules are mostly of three types H O, H] 0, and HD O. For a given sample of water, call the number of moles of each W, W g, and Wq, respectively. Then define the heavyriight ratios as ki8 = Wig/VV and Rp = WqIW. For either water or carbonate, the 5 are defined as deviations of these ratios from standard values for these ratios (call the ratios of the standards Sig and Sq)  

For water, the standard ratios are approximately the average ratios for modern seawater (these standards are called SMOW, or Standard Mean Ocean Water), so and 5D both equal zero for modern seawater (if a standard other than SMOW is used, this will not be true). S values are typically very small numbers and so are usually multiplied by 1000, in which case the units are per mil.  

Much of the variation in these time series for the past 700 kyr can be described by a combination of a 100 kyr cycle plus additional cycles with periods of 20 and 40 kyr. This result immediately suggests that the ice-age cycles are caused by variations in the amount and seasonality of solar radiation reaching the Earth (insolation), because the 20, 40, and 100 kyr periods of climate history match the periods of cyclic variations in Earth s orbit and axial tilt, line hypothesis that these factors control climate was proposed by Milutin Milankovitch in the early part of the 20th century and is widely known as Milankovitch Theory. It is now generally accepted that the Milankovitch variations are the root cause of the important 20 and 40 kyr climate cycles. The 100 kyr cycle, however, proves to be a puzzle. The magnitude of the insolation variation at this periodicity is relatively trivial, but the 100 kyr cycle dominates the climate history of the last 700 kyr. Further, 

22 000 years. The interaction of these two generates precession cycles with periods of 19 000 and 

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Edwards RL, Cheng H, Murrell MT, Goldstein SJ (1997) Protactinium-231 dating of carbonates by thermal ionization mass spectrometiy imphcations for Quaternary climate change. Science 276 782-785... 

Berger, A. L. 1978. Long-term variations of daily insolation and quaternary climate changes. J. Atmospheric Sci. 35, 2362-67. 

Davis, M.B. Shaw, R.G. (2001) Range shifts and adaptive responses to quaternary climate changes. Science, 292, 673-9. 

Kennett et al. Methane Hydrates in Quaternary Climate Change The Clathrate Gun... 

Kennett, J.P., Cannariato, G., Hendy, I.L., Behl, R.J., Methane Hydrates in Quaternary Climate Change The Clathrate Gun Hypothesis, The American Geophysical Union, Washington, DC (2003). 

Cross SL, Seltzer GO, Fritz SC, Dunbar RB (2001) Late Quaternary climate change and hydrology of tropical South America inferred from an isotopic and chemical model of Lake Titicaca, Bolivia and Peru. Quat Res 56 1-9... 

Edwards R. L., Cheng H., Murrell M. T., and Goldstein S. J. (1997) High resolution protactinium-231 dating of carbonates implications for the causes of Quaternary climate change. Science 276, 782-786. 

Saltzman B. (1987) Carbon dioxide and the 8 0 record of late-Quaternary climatic change a global model, dim. Dyn. 1, 77-85. 

Frank, R. M., 1975, Late Quaternary climatic change evidence from cave sediments in central eastern New South Wales, Australian Geograph. Studies 13 154-168. 

Terry, D. O., Jr., Knapp, E. Harbor, D. J., and Thren, R. C., 1999, Clastic sediments of Bathers Cave a potential record of Quaternary climate change in west central Virginia, Geol Soc Am Abstr Programs 31 no. 7 A-233. 

Webb, T., Anderson, K. H., Bartlein, P. J., and Webb, R. S., 1998, Later Quaternary climate change in eastern North America a comparison of pollen-derived estimates with climate model results. Quaternary Science Reviews 17 587-606. 

Goede, A. and Hitchman, M. A., 1983, Late Quaternary climatic change evidence from a Tasmanian speleothem, in J. C. Vogel, ed.. Late Cainozoic Paleoclimates of the Southern Hemisphere, Balkema Press, Rotterdam, pp. 221-232. 

Candy, I., Black, S. Sellwood, B.W. (2004a) Complex response of a dryland river system to Late Quaternary climate change implications for interpreting the climatic record of fluvial sequences. Quaternary Science Reviews 23, 2513-2523. 

Although the main application of amino-acid isomerization is in dating strata, differences in mean temperature between horizons have been estimated, yielding information on Quaternary climatic changes (e.g. Miller et al. 1987).This application requires independent dating and the use of approximate first order kinetics to describe the isomerization. 

Schmidt, D. N., Renaud, S. Bollmann, J. 2003. Response of planktic foraminiferal size to late Quaternary climate change. Paleoceanography, 18, 10.1029/2002PA000831. 

Berger, A. (1978). Long-term variation of daily insolation and Quaternary climatic changes./. Alnios. Sci. 35, 2562-2367. 

Kennett, J., Cannariato, K., Hendy, 1., and Behl, R., 2002. Methane hydrates in Quaternary climate change the clathrate gun hypothesis, AGU books board, 216 p. 

Meyers, P. A., 1990. Impacts of regional Late Quaternary climate changes on the deposition of sedimentary organic matter in Walker Lake Nevada. Palaeogeogr. Palaeoclim. Palaeoecol. 78 229-240. 

Zabel, M., Schneider, R.R.,Wagner,T.,Adegbie,A.T., de Vries, U., Kolonic, S. (2001) Late quaternary climate changes in central Africa as inferred from terrigenous input to the Niger Fan. Quaternary Research, 56, 207-217. 

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