Introduction

The Holocene is the period of approximately the last 11.7 kyr and covers the time from the end of the last ice age up to the present. It therefore includes the so-called anthropocene, which is the period when humankind has influenced the climate system. For most of this latter period there are instrumental meteorological records, and this era is dealt with in the next chapter.

The Holocene marks the return of warmer and more humid conditions after the cold and dry period of the Last Glacial Maximum (LGM) (see Section 4.2.5). The start of the Holocene coincided approximately with the end of the Younger Dryas event (12.8–11.5 kyr BP) (see Section 4.2.5), an abrupt return to cold conditions (stade) during the gradual warming at the end of the last Pleistocene glaciation. Temperatures derived from ice cores collected on the Greenland icecap (see Section 2.4.2) suggest that the transition to the Holocene was a rapid switch of mode, with the Younger Dryas ending abruptly over a period of about 50 years. However, in other parts of the world the transition was not so rapid.

The Holocene can be split into a number of stages, and in this chapter we will divide it into the Early Holocene (11.7–5 kyr BP), the Mid Holocene (5–3 kyr BP) and the Late Holocene (3 kyr BP to present) (see Table 5.1).

Greenland ice core data suggest that temperatures during the Holocene have been about 12 °C higher than during the Pleistocene.