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According to Tuesday’s vog forecast, tradewinds are expected for the next couple of days, so air quality should be good for most of the islands, but the winds will carry the vog from Kau to Kona.
That’s the update from the University of Hawaii’s Vog Measurement and Prediction Project.
If you’re wondering whether vog from Kilauea Volcano will be headed to your neighborhood in the next couple of days, or you want real-time air quality on Hawaii island, then the Vog Measurement and Prediction Project can help.
Vog prognosticator Lacey Holland, like any meteorologist, took some flak from Hawaii islanders when her forecast was at times a little off during the 2018 Kilauea eruption in the lower East Rift Zone.
But “a number of people that saw the forecasts were very grateful that there were forecasts available to help them make preparations,” said the atmospheric sciences researcher and air quality forecaster with the University of Hawaii’s Vog Measurement and Prediction Project.
Vog, or volcanic smog, is a form of air pollution that results when sulfur dioxide and other gases and particles emitted by an erupting volcano react with oxygen and moisture in the presence of sunlight, according to Wikipedia.
Holland puts out a vog forecast twice a day every day, 60 hours in advance, particularly for the vog-sensitive, asthmatic and those with chronic lung conditions.
“We learned a lot from the 2018 eruption,” she said. “What we’ve learned, we’ve put into the model this time around and made a good forecast even better.”
Holland and UH atmospheric sciences professor Steven Businger in 2020 received three years of additional funding from the Federal Emergency Management Agency to continue to provide statewide forecasts of vog and to expand delivery methods to include push notification to smartphones.
After Kilauea’s 2-1/2-year lull, the volcano is pumping out lava at the summit into Halemaumau Crater, and that means sulfur dioxide gas and sulfate aerosols are also being emitted into the atmosphere.
Early on, emission rates were up to 33,000 tons of sulfur dioxide daily, and that has subsided to 3,306 to 7,165 tons a day since Dec. 27.
“Kilauea typically emits between 500 and 14,000 metric tons of sulfur dioxide gas per day during periods of sustained eruption. During the 2018 eruption at Kilauea’s Lower East Rift Zone, SO2 emissions were over 100,000 metric tons per day, in keeping with the increased vigor of that eruption,” according to the U.S. Geological Survey.
Initially, sulfur dioxide is emitted, along with water vapor and other matter.
But by the time it gets to Oahu, it turns to sulfate aerosol and is seen as particulate matter of 2.5 micrometers or less, which often makes for more colorful sunrises and sunsets.
Holland analyzes the data from geochemists and gas chemists. They provide her with sulfur dioxide measurements by using a vehicle or drone to go back and forth to measure the concentrations of the gas and wind speeds to figure out what the emission rates are.
“In my job I don’t measure wind or gases. I run a meteorological model with an air quality model,” she said. The meteorological model is a forecast. An air quality model tells how much sulfur dioxide is in the vog, how it changes, the rate of change and where it’s going.
Ultraviolet spectrometers had been used, but during the 2018 eruption they were covered in ash.
The Hawaiian Volcano Observatory reported a small breakout at about 8 a.m. Tuesday from the lower part of the west vent tube, with a newly exposed lava channel entering the lake, which was 627 feet deep Monday evening. Lava continues to enter the lake through the tube, producing a small dome fountain, which appeared Saturday, measuring about 16 feet high and 33 feet wide.
VOG FORECAST PROGRAM
For information the Vog Measurement and Prediction Project forecast:
>> Visit: weather.hawaii.edu/vmap/index.cgi.
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