Introduction to Holocene Climate Change: new perspectives

Abstract

We live in the Holocene. Its variability is our variability. To fully understand modern climate change we need to accurately record how climate has been changing over the Holocene’s 11700 years, as that is the backdrop to what is happening now. On 4–5 April 2013, the Geological Society examined a range of evidence for changes in the Holocene climate, in a meeting entitled Holocene Climate Change and organized by Colin Summerhayes, Nick McCave, Paul Valdes, Graeme Barker, Eric Wolff and Dan Charman. We hoped to find out more about what governed the occurrence of past cool events such as those that occurred at 8200 years ago and in the Little Ice Age between roughly AD 1300 and 1850, and warm periods such as the Holocene Climate Optimum, the Roman Warm Period, and the Medieval Climate Anomaly. To what extent were these events global, rather than regional? What drove them? What produced roughly periodic changes at intervals of about 1500 years seen in marine sediment records and speleothems? Was it ever warmer in the past 10000 years than it has been in the past 20 years? If so, when, and by how much? Recent improvements in physical stratigraphy, chemical stratigraphy and numerical modelling now allow us to examine in much more detail than before the effects of a wide variety of natural causes, natural cycles and greenhouse gases, and to integrate results from different land, ice and ocean areas in ways not formerly possible, to improve our understanding of Holocene climate change. The meeting was deliberately made broad in scope, covering changes in ocean circulation and sea level, terrestrial change, change in the polar regions, the modelling of any or all of those, and the interaction between climate and humans. As is often the case, many of the 33 papers and …