The most rapid global sea-level rise event of the last deglaciation, known as Meltwater Pulse 1A (MWP-1A), occurred roughly 14,650 years ago. There is considerable uncertainty regarding the sources of meltwater and the relationship between MWP-1A and the fast-changing climate.
Meltwater Pulse 1A was characterized by roughly 20 meter global sea-level (GMSL) rise within 500 years. It was driven by the collapse of large ice sheets and was concurrent with rapid Northern Hemispheric warming and disruptions in oceanic and atmospheric circulation.
Three ice sheets are proposed as the major contributor, namely, the North American Ice Sheet, including Greenland (NAIS), the Antarctic Ice Sheet (AIS) and the Scandinavian and the Barents Sea Ice Sheet (known together as SIS). The NAIS is the dominant contributor accounting for roughly 35 – 85% of total MWP-1A magnitude.
For this study, Yucheng Lin and colleagues used the method of sea level fingerprinting but increased the number of study sites. Previously, only three sea-level sites showed sufficient temporal resolution for fingerprinting studies across MWP-1A. They include coral reef records from Tahiti and Barbados and sedimentary indicators from Sunda Shelf. The relationship between coral living depth and environmental conditions, as well as the link between reef accretion and sea-level change, is not straightforward and may differ between different localities.