This is a Preprint and has not been peer reviewed. This is version 1 of this Preprint.
Downloads
Authors
Abstract
Global mean sea-level (GMSL) change can provide insight on how ice sheets, glaciers, and oceans respond to warming[1;2]. The Holocene (11.7 ka to present) marks a time when temperatures may have exceeded early industrial (1850 CE) values[3]. Evidence from Greenland[4] and Antarctica[5;6] indicates that both ice sheets retreated inland of their present-day extents during the Holocene, yet previous GMSL reconstructions suggest that Holocene GMSL never surpassed early industrial levels7–9. We combine relative sea-level observations with glacial isostatic adjustment predictions from an ice-sheet model ensemble and new estimates of postglacial thermosteric sea-level and mountain glacier evolution to estimate Holocene GMSL and ice volume. We show it is likely (probability P =0.79) that GMSL exceeded early industrial levels in the mid-Holocene (8-4 ka) by up to 1.5 m and that the Antarctic Ice Sheet was likely (P =0.66) smaller than present in the last 6000 years. We demonstrate that Antarctic retreat lags Antarctic temperature by 250 years, underscoring future Antarctic vulnerability to present warming. Comparing our reconstruction to future projections indicates that GMSL rise in the next 125 years will very likely (P >0.9) be the fastest in the last 5000 years, and that by 2080 GMSL will more likely than not be the highest in 115,000 years.
DOI
https://doi.org/10.31223/X5JT11
Subjects
Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
Keywords
Sea level, Holocene, paleoclimate, future, ice sheets, West Antarctic Ice Sheet, climate projection, glacial isostatic adjustment, data assimilation
Dates
Published: 2023-05-24 17:33
Last Updated: 2023-05-25 00:33
License
CC-By Attribution-NonCommercial-NoDerivatives 4.0 International
Additional Metadata
Conflict of interest statement:
None
Data Availability (Reason not available):
Data will be available on acceptance.
There are no comments or no comments have been made public for this article.