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© USGS
Kilauea Volcano - A new eruption near Pu'u 'o'o Crater on the Big Island that began March 5 has led to a dramatic increase in sulfur dioxide gas, one of two main ingredients in vog.

In recent months the east rift zone of Kilauea Volcano had been releasing 300 to 400 tons of sulfur dioxide gas every day.

After the new eruption of the mile-and-a-half long fissure this past Saturday, the amount of SO2 gas has increased to 10,000 tons per day.

"It's hard to say how long that might go on," said United States Geological Survey spokesperson Janet Babb, whose part of a team that helps monitor Kilauea. "The elevated SO2 emission that we're seeing corresponds to that high lava effusion rate."

Currently the new eruption is spewing 2.5 million cubic meters of lava per day in an unpopulated area, five times the recent average of a half million cubic meters per day.

For now the increase in lava and volcanic gas is not having a major impact on residents.

Currently the air quality in all Big Island communities remains moderate to good. However that's mostly the result of sulfur dioxide and sulfate aerosol, the other main ingredient in vog, being blown out to sea.

If Hawaii's typical northeast trade wind pattern were to wane or move to a more southerly direction, the recent increase in volcanic gas could be felt by many. During such conditions vog travels quickly to the other major islands along the Hawaiian chain.

"With these higher emission rates there might be a noticeable difference," said Babb, "particularly for people who are sensitive to the volcanic fumes."

So far the increase in sulfur dioxide has not shown up in air quality sampling. State Department of Health monitoring shows the level of sulfur dioxide in some areas is up to .3 parts per million, which is still far short of the 1 part per million considered hazardous.

"There's not an expected community-wide health effect at those levels," said Hawaii County Civil Defense administrator Quince Mento, "but people that are sensitive may be affected."

USGS geologists were in the process of gathering new SO2 samples on Tuesday after an initial round of testing on March 6 showed the increased levels of volcanic gas. Babb said the latest results should be available soon.

Tracking Vog

Under an eight month old project at the University of Hawaii at Manoa, professor of meteorology Steven Businger is using a computer model to track where vog is likely to travel.

The Vog Measurement and Prediction Project, or VMAP, was made possible through a $300,000 grant from the U.S. Geological Survey.

One of the forecast models predicts the movement of vog 48 hours into the future.

"I would say that the extent of the plume and whether or not you're going to see vog, that aspect of the dispersion modeling has been very effective," Businger told khon2. "We see that the trends are right on."

The current VMAP model is less accurate at predicting concentration levels for sulfur dioxide and sulfate aerosol, however improvements are being planned.

Businger hopes more federal funding will soon allow him to perform what's known as an "ensemble run." Instead of running one computer model twice a day as he does now, as many as 30 computer models could be run simultaneously, providing a wealth of data.

"That will allow the final overlapping results to be presented to the public as a probability," explained Businger. "So we can say there's a 60 percent chance vog will be of a higher concentration than X, and I think that'll make it a much more useful tool."

The professor also hopes to measure the actual height of Kilauea's volcanic plume in future VMAP modeling. That would allow him to determine exactly how high vog producing gases will spread into the atmosphere.

Of course continued funding is the key to any future enhancements.

"The problem of course is we're in very, very difficult fiscal times and smaller government seems to be the key word," said Businger, "so we'll see what happens."