The natural disaster in Hawaii is unspooling in stops and starts, beginning last week with a series of earthquakes and punctuated by volcanic eruptions that continue with no end in sight.
Wednesday afternoon, the Hawaiian Volcano Observatory confirmed that a new fissure in the Big Island's Kilauea volcano rift zone had begun to erupt.
"Vog" is the term used to describe the hazy air pollution caused by volcanic emissions
Water vapor, carbon dioxide and sulfur dioxide gas make up vog
Thursday morning, the observatory announced that the new fissure had paused.
All told, 15 fissures have emerged, 36 structures have been destroyed, and more than 116 acres -- roughly 112 football fields -- have been covered in lava.
Now, hazardous fumes seething within brilliant plumes continue to be released from the volcano's mouth.
Should tourists who'd planned Hawaiian vacations cancel them?
"No," said Janice Nolen, an air pollution specialist and assistant vice president at the American Lung Association.
"What they should do is check to see what the air quality looks like where they are planning to go," she said.
The Environmental Protection Agency's Air Now website provides national data as well as data from air quality monitors at select US embassies and consulates around the world.
Generally, the volcano eruptions are affecting just the south side of the Big Island of Hawaii, and the vog appears to be pulling away from the island -- with some of it blowing out to sea, Nolen says.
'Vog' is a term for the hazy air pollution primarily made of water vapor, carbon dioxide and sulfur dioxide gas, caused by volcanic emissions from the K-lauea volcano, according to the International Volcanic Health Hazard Network.
Sulfur dioxide, ground-level ozone, particle pollution and carbon monoxide are the four major air pollutants regulated by the Clean Air Act and calculated by the EPA to determine air quality index levels.
While most of the Hawaiian islands have escaped the effects of the erupting volcano, people who live in the residential neighborhoods nearest the K-lauea volcano (and not the usual tourist hotspots) may suffer negative health effects caused by vog.
"There are some real concerns because when the eruption happened initially, some of the stuff that came immediately out of the volcano (beside the lava in the air) was sulfur dioxide," Nolen said. "Sulfur dioxide is particularly irritating, especially to people with lung disease. But it can be irritating to anybody's lungs."
Not only can it make breathing difficult, but once sulfur dioxide reaches the atmosphere, it is converted into fine particles (PM2.5), making them easier to inhale, Nolen says.
"Those are things that can be inhaled deep into the lungs," Nolen said. "And those can pose real health risks."
Particles can cause coughing, lead to asthma attacks and so cause heart attacks and strokes. They can shorten life, Nolen says: "Literally kill people."
As of Thursday morning, air quality levels throughout the Hawaii islands are good (with air quality index scores less than 50), with the exception of the southwest area of the big island. There levels are moderate (the scores range from 51 to 100), which is considered acceptable, though for a very small number of people who are unusually sensitive, the level of pollutants may cause some concern.
Staying indoors, with doors and windows closed, can help reduce your exposure to vog for a short time -- just hours, according to the International Vog Health Hazard Network. Over the long term, though, the outdoor air will gradually seep inside, so windows should be opened again when vog levels decrease.
Air cleaners can be effective though air conditioning is not designed to filter out SO2 gas or particles from the air. Still, by dehumidifying the air, some vog components may be pulled out of the air.
"If you're planning on going to the Big Island, for example, there's the national park there, know that there are alerts you should be aware of, so check and see," Nolen said. "But it's not a reason to cancel the trip."
Nolen says that checking online air quality information is always a smart move whenever you're traveling. People who have asthma, lung diseases or cardiovascular disease "need to check with their doctor about making sure they are ready for any air quality issues," she said. "So they know what they should do, have their medicines and have their plan in place."
A plan is necessary so you know what to do if your symptoms are triggered by something air-related, Nolen says: "It's a good idea for anyone with health issues to think about air quality anywhere they are, including where they live."
Generally, Honolulu has very little air pollution and was ranked one of the cleanest cities in the United States by the American Lung Association.
What's happening in Hawaii now -- a cascade of quakes, an erupting volcano, molten lava covering streets and plumes of vog visible from miles away -- is a simple reminder of exactly how precarious this earthly existence can be.
"Know that It's one of those unusual naturally occurring events that helps us to see the impact of air quality on lots of different people in places we don't normally expect," Nolen said. "Prepare and adapt."