The School of Earth and Atmospheric Sciences Presents Dr. Isabel Nias, NASA Goddard Space Flight Center

Quantifying and Reducing Uncertainty in Projections of Sea Level Rise from Ice Sheets

Rising sea levels pose a serious threat to coastal regions around the world, and planners need accurate projections to ensure the adequate provision of coastal defenses. A major source of sea-level rise is mass loss from the Antarctic and Greenland ice sheets. 

However, making projections of the future contribution from ice sheets is a challenge, due to numerous sources of uncertainty that cascade down throughout the modeling process. For example, numerical ice-flow models are initialized with various input datasets, such as ice sheet geometry and velocity, all of which have errors associated with them. Furthermore, these models rely on parameterization to represent physical processes, such as basal sliding and viscous flow, while other processes are missing entirely. 

Running an ice-flow model into the future also requires atmospheric and oceanic forcings to account for the changing climate, which have their own uncertainties. All of these factors contribute to the overall uncertainty in projections of sea-level rise. In this talk, I will present work that seeks to understand, quantify and reduce the uncertainty associated with modeling the Antarctic and Greenland ice sheets.