This report is the first in a two-part series chronicling an international workshop on sea-level rise, held at UC San Diego last week. Leading climate scientists and public-policy experts shared research findings and formulated strategies to combat and adapt to projected short- and long- term rises in sea level. Part 2, to be published in the Sept. 27 issue, examines the measures coastal cities around the world are already adopting.
By Lynne Friedmann
Sea level is on the rise and demands the attention of policymakers and urban planners to identify and set in motion specific, achievable actions over the next several years to mitigate or adapt to a rise in sea level over the next 300 years of between 2.4 and 5 meters (8 and 16 feet), based on current understanding and circumstances.
This was the message of the International Workshop on Coastal Cities, Climate Change, and Sea-Level Rise, held Sept. 5-7, on the UC San Diego campus where representatives from 18 leading research institutes — members of the Association of Pacific Rim Universities (APRU) and a number of non-government organiza- tions — explored ways of improving cooperation among academics, government officials, and policymakers to protect human lives and economic resources.
It is not often that an issue brings together climate scientists, economists, architects, urban planners, political scientists, and international relations experts. But, that’s exactly who was in the room, motivated to find solutions to the potentially catastrophic effects of sea-level rise on 200 million people and trillions of dollars of coastal assets ($100 billion alone in California).
The first day of the meet- ing provided clear and co- herent presentations of the latest research outcomes on climate change at different locations around the world.
“The conclusion is that climate change and local sea-level rise is highly variable,” said Jim Falk, Honorary Professorial Fellow in the University of Melbourne (Australia) School of Land and Environment and director of climate change research for APRU. “This calls for needs assessment city by city, region by region.”
Jeff Severinghaus, professor of geosciences at Scripps Institution of Oceanography (SIO) at UCSD, said, “The Earth is like a waterbed, when you ‘step’ on it in one place, it rises in another.”
Accounting for sea-level rise differences are factors such as wave and storm surge, El Niño climate patterns, topography, land subsidence, or a rise in land elevation (as can occur in highly seismic areas of California).
Much focus in recent years has been on the contribution of melting polar ice to sea-level rise.
“Melting itself is not a climate change (affect),” said Helen Fricker, professor, Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics, at SIO. “Melting of ice is normal.” The problem is that current ice melting is faster than has occurred historically.
When the margins of ice shelves thin, glaciers behind them respond to gravity and are pulled to the sea. Most ice-shelf thinning is related to warm ocean currents. But it’s only been recently that melting ice has made a contribution to rising sea- level rise.