WAIKIKI (HawaiiNewsNow) - Imagine Waikiki without its world-renowned beach.
That's a future that's possible this century, scientists say. And it's among a host of threats climate change poses to Hawaii and to its no. 1 economic engine — tourism.
After all, rising sea levels won't just devour Waikiki.
In coastal communities statewide, they'll trigger tough decisions — about whether to beat a strategic retreat, to move property and infrastructure away from the encroaching seas, or to use limited resources to hold back the waves.
Climate change puts at risk, too, the infrastructure that makes tourism (and, more broadly, a thriving business sector) possible, from Honolulu's airport to the state's utilities to oceanfront hotels to coastal byways.
And it means the likelihood that Hawaii will see more severe, extreme weather events will increase, and that the state's very natural environment — its flora and fauna — will be at risk.
For many, a summer with record-breaking king tides, which have swallowed up stretches of Waikiki Beach and pushed water into parking lots and roads, has pushed the specter of climate change to the forefront and underscored the urgent need to plan now for climate change and its impacts over the next 80 years.
"You don't want to wait for a catastrophe to happen before you start to react and say, 'Man, we should have done this,'" said Mufi Hannemann, president and CEO of the Hawaii Lodging and Tourism Association.
"So there is a lot of ongoing discussion taking place now, and that's what's also being factored into some of the expenses that some of our hotels have going forward. They are not just talking about renovating and building a new hotel or a new building. When you are close to the shoreline, you also have to take that expense into account."
How much are Hawaii's beaches worth?
This summer, when tides rose to record-breaking levels, Waikiki Aquarium Director Andrew Rossiter could see waves crashing higher than his second floor office as they slammed into the short wall behind the attraction.
"We are literally 10 feet from the ocean," Rossiter said. "If we do stay here, we will have to build some sort of retaining wall to keep the water out."
The aquarium is just one of hundreds of coastal businesses facing an uncertain and expensive future as Hawaii's climate shifts.
Since the 1950s, Pacific Ocean temperatures have been warming up. And the National Climate Assessment has projected ocean waters to warm by 2.3 degrees by 2055 and by 4.7 degrees at the end of the century.
Additionally, the group has shown sea levels rising by 1.3 inches per decade, potentially adding up to multiple feet by the end of the century.
The numbers may seem small, but they will have monumental impacts on Hawaii's economic future.
By 2100, conservative models put sea level rise in Hawaii at upwards of 4 feet. At those inundation levels, hundreds of near-shore homes and businesses would be at risk, along with key transportation corridors and core infrastructure, including water and sewer lines.
"Yes, we should be concerned about it," said Denise Konan, director for the Center of Sustainable Coastal Tourism at the University of Hawaii, which is conducting a Hawaii Tourism Authority-funded study to look at the potential impacts of climate change on Hawaii's hospitality industry.
"But I do also think it is a great opportunity to take responsibility for the future."
What does that responsibility look like? That's not yet clear.
What is clear, Konan said, is that Hawaii is a tourism mecca because of its beaches.
"You have to realize what kind of value our coastlines create," Konan said.
According to the Hawaii Tourism Authority, nearly 9 million visitors poured over $15.6 billion into the state in 2016.
Already this year, tourists have spent a total of $8.4 billion, an increase of nearly 9 percent compared to the first half of last year.
But what if Waikiki beach disappeared?
According to a 2008 study, the most comprehensive to date predicting Waikiki losses, the loss of the beach in Waikiki alone could cost the state $2 billion in visitor expenditures.
The Waikiki Improvement Association also surveyed visitors to see if they would return to the area if the beach disappeared. Fifty-eight percent of mainland visitors would not even consider staying in Waikiki.
And rising sea levels in spots like Waikiki wouldn't just mean fewer visitors. Homes, businesses and grocers could also be in the inundation zone.
"The beach is a buffer for businesses," said Rick Egged, president of the Waikiki Improvement Association. "Having the beach in place will help us to provide that buffer not just for sea level rise, but also storms."
But that's not all. The latest report from the Environmental Protection Agency says the average U.S. temperature will rise by about 3 to 12 degrees by 2100. And among the many reasons why Hawaii is seen as the ultimate tourist destination is because of its predictable weather.
Kevin Hamilton, UH atmospheric science researcher and former director of the International Pacific Research Center, says many visitors enjoy the tropical, trade wind weather the islands has to offer, but the hotter it gets, the more visitors will look to other destinations that may be more desirable.
"A lot of our tourist industry basically depends on the fact that we have typical weather that's very enjoyable for most people," Hamilton said. "But if our summer temperatures are all 4 or 5 degrees Fahrenheit warmer, a day like today ... could become quite uncomfortable."
'Yes, there are going to be challenges'
It's tough to plan for climate change for a lot of reasons. Perhaps one of the biggest: The scope of the impacts aren't exactly known.
But Konan said prep, planning and investment now will be well worth it — and could well mean smaller payouts later.
"If we think about it as a long-term investment, the net present value of that investment is going to be small as compared to the 50-year, 100-year value of having more secure coastal areas," Konan said.
And, Egged noted, there is already some work underway.
The Waikiki Improvement Association, for example, is working with city officials to restructure pipelines for decades to come.
"We already have backup into the streets with backwater," Egged said. "We are looking at water channels to see where water backs up in normal to normal-heavy rain."
But, Egged added, much of the financial burden for securing coastline properties in the future will fall on private owners.
Entities like the Waikiki Aquarium, which sits just a few feet from the ocean.
Rossiter said the aquarium is already resurfacing walls and looking into longer-term projects to save it from the water, but not without a cost.
"It is going to cost a lot of money and a big investment to build something to keep the water out," Rossiter said.
Despite all the challenges the state faces, though, Konan said Hawaii has been active in sustainability efforts and can serve as an example for other islands and countries on how to prepare for climate change impacts.
"Yes, there are going to be challenges," Konan said. "But Hawaii is the kind of place that is going to figure it out."
This is part of an ongoing Hawaii News Now digital series exploring climate change and its impacts in Hawaii.
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