Abstract
The Last Interglacial (LIG) stage (ca. 130–115 ka) provides a relatively recent example of a world with both poles characterized by greater-than- Holocene temperatures similar to those expected later in this century under a range of greenhouse gas emission scenarios. Previous analyses inferred that LIG mean global sea level (GSL) peaked 6–9 m higher than today (Kopp et al. 2009; Dutton & Lambeck 2012). Here, we extend our earlier work to perform a probabilistic assessment of sea level variability within the LIG highstand. Using the terminology for probability employed in the Intergovernmental Panel on Climate Change (IPCC) assessment reports, we find it extremely likely (95% probability) that the paleo-sea level record allows resolution of at least two intra-LIG sea level peaks and likely (67% probability) that the magnitude of low-to-high swings exceeded 4 m. Moreover, it is likely that there was a period during the LIG in which GSL rose at a 1000-year average rate exceeding 3 m/ky, but unlikely (33% probability) that the rate exceeded 7 m/ky and extremely unlikely (5% probability) that it exceeded 11 m/ky. These rate estimates can provide insight into rates of Greenland and/or Antarctic melt under climate conditions partially analogous to those expected in the twenty- first century.