SECTOR: ENVIRONMENTAL SCIENCE

The ice age cometh, does a glacier hold the secret of how civilisation began and how it may end?

Figures referenced in article

Figure 1. A view of core from the North Greenland Ice Core Project website. Note the layers of summer and winter snow are visibly different. Greenland ice is excellent in preserving such clear records.

Figure 2. A temperature history of 40,000 years from earlier ice core studies in Greenland. Note the temperature spikes between 10,000 and 20,000 years and the relative stability in the beginning of the Holocene ( 10,000 years ago). Copied from the "ice core working group document, 1998. Reprinted there from Cuffey et al., Science, 270, 455-458. ©1995, American Association for the Advancement of Science.

Figure 3. Various climate records from the Vostok ice core (East Antarctica) covering the last 160,000 years. Copied from the "ice core working group document, 1998. Included are the CO2 and CH4 greenhouse gas records, which are closely tied to Antarctic temperature variations over the last full glacial/interglacial climate cycle (Lorius et al., 1985; Barnola et al., 1987; Jouzel et al., 1987; Chappellaz et al., 1990). Temperature data are plotted as deviations from the present day mean annual temperature of -56oC. Comparisons like these are important for deducing the impact of changing greenhouse gases on climate.