The Framework for Assessing Changes To Sea-level (FACTS) v1. 0-rc: A platform for characterizing parametric and structural uncertainty in future global, relative, and extreme sea-level change

Robert E. Kopp, Gregory G. Garner, Tim H. J. Hermans, Shantenu Jha, Praveen Kumar, Aimée B. A. Slangen, Matteo Turilli, Tamsin L. Edwards, Jonathan M. Gregory, George Koubbe, Anders Levermann, Andre Merzky, Sophie Nowicki, Matthew D. Palmer, and Chris Smith

PaperAbstract. Future sea-level rise projections are characterized by both quantifiable uncertainty and unquantifiable, structural uncertainty. Thorough scientific assessment of sea-level rise projections requires analysis of both dimensions of uncertainty. Probabilistic sea-level rise projections evaluate the quantifiable dimension of uncertainty; comparison of alternative probabilistic methods provide an indication of structural uncertainty. Here we describe the Framework for Assessing Changes To Sea-level (FACTS), a modular platform for characterizing alternative probability distributions of global mean, regional, and extreme sea-level rise. We demonstrate its application by generating seven alternative probability distributions under multiple alternative emissions scenarios for both future global mean sea level and future relative and extreme sea level at New York City. These distributions, closely aligned with those presented in the Intergovernmental Panel on Climate Change Sixth Assessment Report, emphasize the role of the Antarctic and Greenland ice sheet as drivers of structural uncertainty in sea-level rise projections.