The last glacial maximum occurred at 18Ka. By 14Ka, the ice sheets of the Northern Hemisphere had already began retreating, and by 6Ka, global climate reached a Holocene thermal maximum. The Holocene Epoch is thus delineated as a period of relative warmth, and is considered to be an example of an interglacial episode that occurs in conjunction with glaciations throughout the Quaternary. The penultimate interglacial occurred at about 120Ka (Figure 5.12).
A number of text books discuss in great detail the climatic events of the last 10,000 years. Lamb (1982) provides a particularly useful commentary, whilst Bradley & Jones (1992) discuss the evidence for climatic variations since A.D. 1500. In this section, I shall be concerned with century to millennia time scales, and in this respect, I will review only the most significant climate changes which serve to illustrate the relevant climate forcing mechanisms.