Professor Rob Deconto, University of Massachusetts-Amherst

The Paris Climate Agreement and Future Sea-Level Rise from Antarctica
Monday, March 12th
Geocorner 105
4:00 p.m.

Emerging science, based on a combination of observations, glaciological theory, and numerical modeling, suggests Antarctica could become the single greatest contributor to sea-level rise in the second half of the 21st century. In fact, recent ice sheet modeling has shown that Antarctica has the potential to contribute more than 50 centimeters of sea-level rise by the year 2100.

Here, we’ll discuss the implications of updated Antarctic ice sheet modeling, using new model physics representing previously underappreciated glaciological processes including hydrofracturing of ice shelves and mechanical failure of tall, marine-terminating ice cliffs. The model is tested and calibrated against modern and past ice-sheet behavior, and then applied to future climate scenarios. The scenarios represent a wide range of future greenhouse gas emissions trajectories, including a fossil-fuel intensive (business as usual) scenario versus the emissions aspirations of the 21st Conference of the Parties (COP21) of the United Nations Framework Convention on Climate Change, aimed at limiting the post-preindustrial rise in global mean temperature to less than 2ºC at the end of this century, and to promote further efforts to limit the warming to 1.5ºC.

The results show that a global temperature rise less than 2ºC substantially reduces the risk of catastrophic sea-level rise from Antarctica. However, they also show that the current, Intended Nationally Determined Contributions (INDCs), allowing global mean temperature to approach ~3ºC by the end of this century, might be insufficient to save the West Antarctic Ice Sheet from major retreat, with dire consequences for low lying islands, coastlines, and major population centers.


Rob DeConto is a Professor of Geosciences at the University of Massachusetts-Amherst. His background spans geology, oceanography, atmospheric science, and glaciology, and he has held research positions at both the US National Center for Atmospheric Research (NCAR) and the National Oceanic and Atmospheric Administration (NOAA). Rob’s research is focused on understanding the long-term evolution of the Earth’s cryosphere, particularly the great polar ice sheets on Greenland and Antarctica, and the future fate of those ice sheets in a warming world. This has included field work on Antarctica, the development of climate, ocean, and ice sheet models, and the application of those models to a wide range of past and future climate scenarios. Rob serves on a number of national and international science boards and advisory panels. He is the 2016 recipient of the Tinker-Muse Prize for Science and Policy in Antarctica, and he is currently serving as a lead author for the Intergovernmental Panel on Climate Change (IPCC).