The early Holocene sea level rise

Abstract

The causes, anatomy and consequences of the early Holocene sea level rise (EHSLR) are reviewed. The rise, of ca 60m, took place over most of the Earth as the volume of the oceans increased during deglaciation and is dated at 11,650–7000 cal. BP. The EHSLR was largely driven by meltwater release from decaying ice masses and the break up of coastal ice streams. The patterns of ice sheet decay and the evidence for meltwater pulses are reviewed, and it is argued that the EHSLR was a factor in the ca 8470 BP flood from Lake Agassiz-Ojibway. Patterns of relative sea level changes are examined and it is argued that in addition to regional variations, temporal changes are indicated. The impact of the EHSLR on climate is reviewed and it is maintained that the event was a factor in the 8200 BP cooling event, as well as in changes in ocean current patterns and their resultant effects. The EHSLR may also have enhanced volcanic activity, but no clear evidence of a causal link with submarine sliding on continental slopes and shelves can yet be demonstrated. The rise probably influenced rates and patterns of human migrations and cultural changes. It is concluded that the EHSLR was a major event of global significance, knowledge of which is relevant to an understanding of the impacts of global climate change in the future.