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3 From Summary for policymakers, Houghtonet al.,Climate Change 2001:
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4 See, for instance, Crowley, T. J. 2000. Causes of climate change over the
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5 More information in Mitchell, J. F. B.et al. (Chapter 12). In Houghtonet al.
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6 For more information about paleoclimates and how they are investigated
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7 Folland, C. K.et al.(Chapter 2). Figure 2.22. In Houghtonet al.,Climate
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8 See also Raynaud, D.et al., 1993. The ice core record of greenhouse gases.
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9 Berger, A. and Loutre, M. F. 2002.Science, 297 , 1287–8.
10 Petit, J. R.et al. 1999.Nature, 399 , 429–36.
11 Broecker, W. S. and Denton, G. H. 1990. What drives glacial cycles?Scien-
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12 More information in Chapter 5, see especially Figure 5.18.