A heuristic evaluation of long-term global sea-level acceleration

Abstract

In view of the scientific and social implications, the global mean sea-level rise (GMSLR), its possible causes and future trend have been a challenge for long. For the 20th century, reconstructions generally indicate a rate of GMSLR in the range of 1.5 to 2.0 mm yr−1. However, the existence of non-linear trends is still debated, and current estimates of the secular acceleration are subject to ample uncertainties. Here we use various GMSLR estimates published on scholarly journals since the 40’s for a heuristic assessment of global sea-level acceleration. The approach, alternative to sea-level reconstructions, is based on simple statistical methods and exploits the principles of meta-analysis. Our results point to a global sea-level acceleration of 0.54±0.27 mm/year/century (1σ) between 1898 and 1975. This supports independent estimates and suggests that a sea-level acceleration since the early 1900’s is more likely thancurrently believed.