NEWS | April 11, 2019

A meeting of minds: scientists, planners face challenge of rising seas

NASA's Sea Level Change Team during the March meeting in Annapolis, Maryland. Credit: Steve Nerem.

By Pat Brennan,
NASA's Sea Level Change Portal

The question: How can NASA sea-level science be placed in the hands of decision-makers? Some of the answers began to take shape recently on the sunlit shore of the Chesapeake Bay.

Fifty members of NASA’s Sea Level Change team met in March with city planners, Naval officials and others at the Phillip Merrill Environmental Center in Annapolis, Maryland – 29 in all, considered “stakeholders” in planning for sea-level rise in the mid-Atlantic region.

The location wasn’t chosen just for scenic charm. Annapolis is among the U.S. coastal cities that are already feeling the powerful effects of rising seas. Its colonial-flavored City Dock, a magnet for tourists, experiences significantly more nuisance flooding than it did in the past.

“We know that 50 years ago, the historic district flooded 10 days a year,” Annapolis Mayor Gavin Buckley told the group on the opening day of the conference. “Now it’s more than 40. Flooding is higher, and it takes longer to recede.”

Such stories have become familiar to city planners up and down the East Coast and in places like Florida and Louisiana. In Annapolis, statistics on sea level rise are often paired with other grim numbers: a drop in tourism revenue because of flooded streets, parking lots and walkways.

The three-day workshop began with accounts of the real-world effects of sea level rise, such as tidal flooding in Annapolis as seawater rises up through street drainage systems in the coastal zone. Planners described improvement projects designed to fix the problem, and that will cost millions.

But members of the sea level science team were seeking answers to other questions as well: How is NASA science being used for coastal planning, and who is using it? How can NASA best provide useful information as these planning efforts continue?

“We’re looking at ways to integrate NASA knowledge tools into the decision-making process,” said Nadya Vinogradova, program scientist at NASA headquarters in Washington, D.C. and a member of the sea level team.

That includes scientific missions, many using satellite data, making increasingly accurate and precise measurements of sea level change around the world.

The stakeholders’ reaction to the science team was “overwhelmingly positive,” said Ben Hamlington, a sea level researcher at NASA’s Jet Propulsion Laboratory in Pasadena, California, and the leader of the sea level science team.

The stakeholders felt they were “heard,” he said, and good connections were made.

Still, he said, many scientists sensed a lack of broad-based awareness of scientific issues among some who attended. He thought a good next step would be to provide attendees with more information about active scientific research, as well as a contact list of scientists.

The rest of the conference included updates on just these kinds of research projects, from nailing down the sea level “budget” – how various contributing factors add up to the globally averaged rise in sea levels – to significant advances in our understanding of how land surfaces and ice sheets interact. Science team members also made major progress in studies of vertical land motion – the slow rise of land after the melting of glaciers from the last ice age, or the subsidence of coastal land areas because of groundwater pumping and other factors. Accurately measuring these changes is important for regional sea-level-rise projections.

The science team turned next to an assessment of the NASA Sea Level Portal, a web site geared in part toward data sharing and interaction among team members. Some aspects of the portal were seen as effective and useful, including articles on research and improvement of the portal’s “Understanding Sea Level” section. But Hamlington saw a need for broader engagement among team members with the portal itself.

Last, the group considered the future direction of the Sea Level Change team. They proposed possible “team products” as major goals, including a set of sea level projections. These would be developed over the long-term, possibly taken on by the next sea level science team. It would be the third such team to be constituted since the creation of the first team in 2014.

Another group project could include a web-based tool, made available on the portal, for estimating changes driven by vertical land motion. The team also discussed producing fact sheets, or a kind of “report card,” on sea level changes for cities and other specific coastal locations.

Hamlington and others, meanwhile, continue their work on a team paper reviewing the state of sea level science, with a strong focus on observations that will lead to a more refined understanding of regional sea level rise along the coasts.

The mutual effort is likely to foster more interdisciplinary collaboration, as well as an integrated approach to sea level research, he said.