Thursday, April 4, 2013

'A better path' toward projecting, planning for rising seas on a warmer Earth

Terra Daily via SPX: More useful projections of sea level are possible despite substantial uncertainty about the future behavior of massive ice sheets, according to Princeton University researchers.

In two recent papers in the journals Nature Climate Change and the Proceedings of the National Academy of Sciences (PNAS), the researchers present a probabilistic assessment of the Antarctic contribution to 21st-century sea-level change.

Their methodology folds observed changes and models of different complexity into unified projections that can be updated with new information. This approach provides a consistent means to integrate the potential contribution of both continental ice sheets - Greenland and Antarctica - into sea-level rise projections.

"No single ice sheet model or methodology for projections provides sufficient information for good policy and planning decisions," explained lead author Christopher Little, a postdoctoral research associate in the Program in Science, Technology and Environmental Policy in Princeton's Woodrow Wilson School of Public and International Affairs.

"Furthermore, there are fundamental limitations in the observational data available on and near ice sheets," Little said. "Projections of their response to 21st century climate changes are thus very poorly constrained. There's unlikely to be a single answer in the near future: a better objective is a comprehensive, transparent baseline that can be improved over time."...