Scientists say sea is rising faster than first thought

Marilee Wallace was looking at Puna properties Thursday and noticed about half of the homes real estate agents showed her were oceanfront.

“Now show me properties that aren’t on the water but will be later,” she said she told an agent.

Wallace may have legitimate concerns, according to a group of scientists presenting the latest information about sea level rise and its effect on the Hawaiian Islands.

At a public information meeting Thursday evening, the prognosis was mostly grim from the scientists working on a report in conjunction with the state Department of Land and Natural Resources. The group plans another meeting from 6-8 p.m. Tuesday at the West Hawaii Civic Center.

The Sea Level Rise Vulnerability Assessment and Adaptation Report is scheduled to be published at the end of the year. The draft document is making its rounds of the islands as the state solicits comments.

“The sea level is rising as we speak,” said Sam Lemmo, administrator of DLNR’s Office of Conservation and Coastal Lands. “We’re having to really dance on our feet and adapt to the rapidly changing conditions around us.”

The rising ocean could cost the state $19 billion in lost land and structures, untold millions more in lost infrastructure such as roads and utilities, 116 miles of roadway flooded, 6,500 structures flooded, 20,700 displaced people and the loss of 550 cultural sites by the year 2100, according to the most recent scientific modeling and economic projections.

The Big Island, with its unique coastline, is considered a little less exposed, and could see $430 million in lost land and structures, about 2 miles of roadway flooded, 130 flooded structures and 1,900 displaced people by 2100, based on a projected sea level rise of 3.2 feet.

“The idea is to get out in front of it and maybe get a way to manage it better,” Lemmo said.

Recent anomalies such as king tides are indicators of the rapid changes, he said.

The report recommends ongoing research, plans and strategies to save beaches and cultural resources and better planning, said Catherine Courtney, a marine environmental scientist at consultant Tetra Tech. She said she’s been meeting with local government officials during the group’s tour of the islands.

“We need to do a better job of how to use our land. … We need much more collaboration within our government,” Courtney said.

More information about the project, including enabling legislation, is available at the Hawaii Climate Adaptation Portal at http://climateadaptation.hawaii.gov. An interactive map app is also planned.

Three factors contribute to sea level rise, according to Bradley Romine, a coastal management specialist with the Sea Grant Program at the University of Hawaii. About one-third comes from thermal expansion — the ocean takes up more room as it heats up, one-third comes from the melting of the glaciers and ice caps, and another third comes from the melting of the ice sheets in Antarctica and Greenland.

One of the biggest culprits in trapping heat in the atmosphere is carbon dioxide, Romine said. CO2 levels have increased 100 to 200 times faster over the last decade than what the planet experienced during the transition from the last Ice Age, according to studies by the National Oceanic and Atmospheric Administration at the Mauna Loa Baseline Atmospheric Observatory.

“It’s very concerning we’re getting into new territory in temperature,” Romine said.

Burning fossil fuels, coupled with deforestation, are considered the main causes of the CO2 increase.

“Our carbon footprint is actually pretty small compared with what is happening on the continents,” Lemmo said. “But we’re going to suffer some of the worst impacts.”

Most of the audience of about 25 were fully on board with the presentation. But Bill Hanson questioned whether the current changes are really different. “Erosion has happened over the thousands or millions of years. It’s a naturally occurring thing,” Hanson said. “We may not be the bad guys here.”

Those wishing to weigh in on how to address the state’s vulnerability to sea level rise can email Lauren Yasaka, planner with the Office of Conservation and Coastal Lands at lauren.e.yasaka@hawaii.gov.