WAIMEA, Hawaii Island — Vog from the Kilauea eruption that is now in its second month has led to some travelers cancelling Kona-Kohala coast vacation plans.

“We’ve seen a very large number of cancellations,” said Jason Cohn, vice president of marketing for Kona-based Hawaii Forest & Trail tours. “We’re looking at a 20 to 30 percent reduction for the month of June.”

Only one of the company’s five Big Island tours has remained immune to cancellations: “The (Mauna Kea) summit tour. There’s a waiting list for that. It’s been a lifesaver,” Cohn said.

Anthony Quintano/Civil Beat

Local hoteliers and tour operators have been receiving numerous calls from semi-panicked people planning Big Island trips.

“People have seen the national news,” said Marylei Drake, a manager at the 16-room waterfront Kona Tiki Hotel. “They call with lots and lots of questions and ask, ‘Should we cancel?’”

The Oahu-born Drake has ready answers: “No, the volcano is not close to Kona. The volcano is on the other side of the Big Island, some 90 miles distant. Yes, it has been erupting for some 15 years; Kona’s air quality depends on the trade winds.”

When active, the trades, blowing northeast to southwest, keep the bulk of Kilauea’s vog away from the Kona-Kohala coast. “But when they die down, we do see it in the air,” Drake said. “We’ve seen just five or six cancellations.”

The vog that reaches Kona-Kohala is composed mostly of sulfur dioxide and sulfate. Only the sulfate is visible, and over Kona on a particularly thick day, that part of the vog can appear as gray haze tinged with brown.

Andrew Perala/Civil Beat

A major atmospheric pollutant, vog comes from gas emitted from Kilauea’s erupting lava. U.S. Geological Survey scientists have estimated Kilauea’s recent output of sulfur dioxide to be 10 or more times the typical output of the active volcano, reaching an estimated tens of thousands of tons per day.

All that vog can irritate people’s eyes and throats.

“Like the smog in a city,” said Curtis Helton, 56, a Dallas resident vacationing on the Big Island with his wife, Tracey, 55.

The couple had stopped Saturday afternoon on their circle-island drive to see the Kona-Kohala coastline from an outlook on the Kohala mountain road. Kona was not visible through the vog, nor was the Hualalai volcano backing the seaside town.

But at the lookout, the air was clear thanks to gusty trade winds.

“It’s a beautiful day,” said Tracey Helton. “I am so glad we didn’t cancel our vacation.”

The Texas couple spent their 10 days on the Big Island at a Volcano village bed and breakfast. They were not afraid of the volcano’s rumbling earthquakes or the Halemaumau steam explosions.

“I know it’s really bad for the people who lost their homes,” said Curtis Helton. “We were bounced out of bed by an early morning earthquake at our Volcano bed and breakfast. It was something really different than what we’re used to.”

The Heltons arrived on the Big Island the day after this eruption’s massive flow reached the ocean at Kapoho.

“Our (Paradise) helicopter pilot was flying left and right around the steam plumes,” he said, banking his hand through the air. “It was fantastic!”

The Big Island’s premier crop – Kona coffee – is doing well so far.

Airport visitor numbers have rollercoastered since the eruption began May 3. The daily average number of visitor arrivals for the first week of June at the Kona and Hilo airports was actually up by about 2,800 over 2017, to 18,571, according to data compiled by the Hawaii Visitors and Convention Bureau.

Still, Hawaiian Airlines announced Monday that flights from Honolulu to Kona and Hilo would be cut back in the evenings due to declining passenger numbers.

For Big Island farmers like those who own Puna’s papaya plantations, the eruption has been devastating. Current estimates range from 30 percent to 80 percent of the crop lost. But the Big Island’s premier crop – Kona coffee – is doing well so far.

“We have not received a single report of damage to coffee from Kona (farms),” said Allen Franzen, manager of the U.S. Department of Agriculture’s farm assistance program for Hawaii and the Pacific islands.

“But that could change if the winds change,” Franzen said, because coffee blossoms are very susceptible to vog, which can kill the budding flowers.

And unfortunately, a change in the wind was in the forecast as of Wednesday afternoon.

“Vog is predicted to increase significantly through Friday as trade winds fade to variable winds of 10 mph and less,” according to the University of Hawaii Manoa’s Meteorology Department of the School of Ocean Science and Earth Technology.

Vog is expected to curl around the southern half of the Big Island, thickening to warning levels for the southern half between Puna and south Kona, and up to the summit of Mauna Loa. By Friday, or earlier, vog is predicted to drift north along the Kona-Kohala coastline, reaching Waimea and Kawaihae, and possibly north Kohala.

SOEST’s vog map prediction shows vog approaching Oahu, but not directly contacting land.

Here are some links to additional information about vog:

• Advice for visitors to Hawaii from the state Hawaii State Department of Health

• The University of Hawaii’s Vog Measurement and Prediction Project

• Hawaii Interagency Vog Information Dashboard

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