Figure 19. The Earth's temperature (after Hollander, 2003). A. Global surface air-temperatures (1880-2000) (after Hansen et al., 1999, with permission of Journal of Geophysical Research). B. Historical global temperature trends over the last 800,000 years. Temperatures were inferred from oxygen-isotope ratios in sea-floor fossil plankton, based on data from several studies (after Crowley, 1996, with permission of Consequences).