LIHU‘E — Global warming and one of its major byproducts — sea-level rise — will not swallow the Hawaiian Islands whole, but will gradually creep into people’s lives, University of Hawai‘i professor Dr. Chip Fletcher warned the Kaua‘i Planning Commission.
LIHU‘E — Global warming and one of its major byproducts — sea-level rise — will not swallow the Hawaiian Islands whole, but will gradually creep into people’s lives, University of Hawai‘i professor Dr. Chip Fletcher warned the Kaua‘i Planning Commission.
The coastal geologist in UH’s School of Ocean and Earth Science and Technology’s Department of Geology and Geophysics urged the commission during a presentation at its June 23 regular meeting to keep global warming and sea-level rise in mind as they plan Kaua‘i’s future.
He said Hawai‘i should plan for a three-foot rise in sea level by the end of the century, pointing to California’s statewide objective to have all agencies take into account an expected 1.4-meter (approximately 4.5-foot) sea-level rise when making all planning decisions.
“I don’t think we’re going to be under water. I don’t think we’re going to be surfing down Kalakala Avenue,” Fletcher said. “We’re going to gradually be impacted. … Slowly salt water will be coming into our daily existence.”
While ice-melt from Greenland, the world’s second-largest ice mass after Antarctica, won’t reach Hawai‘i for up to 50 years, thermal expansion of the ocean caused by increasing water temperatures will have a very real and more immediate impact, he said.
“This is happening already,” but it is so subtle and slow that people don’t see it entering our lives, Fletcher said. “It’s drainage that will be our biggest problem. … We’re going to have urban wetlands and urban estuaries.”
Currently, the annual high tide in Honolulu puts salt water in a drainage ditch alongside a road fronting the Ala Wai Canal, but soon the high tide of the month or even the daily high tide could be causing similar problems, Fletcher said.
Furthermore, a higher sea level will increase the damage caused by large wave events. At current levels, only the 25-year wave has enough power to reach into some low-lying coastal O‘ahu neighborhoods, but Fletcher said a rise in sea level of only one foot could put large waves into human-populated areas annually.
Fletcher encouraged the commission to begin planning for the eventuality of higher sea levels by requiring sea-level rise assessment on permits and environmental assessments and designing infrastructure and building codes to meet risk, comparing developing near the shoreline to building a home on the side of Kilauea’s active volcano.
“We can buy decades and generations of time if we begin to build this into our plans,” he said. “Our future will be of our own making.”
Video of Fletcher providing his presentation at a separate event can be viewed at www.soest.hawaii.edu/coasts/sealevel/ChipsTalk.html.
• Michael Levine, assistant news editor, can be reached at 245-3681 (ext. 252) or mlevine@kauaipubco.com
