Volcanic Smog or Vog
Vog is basically volcanic smog. The constant eruption of the Kilauea Volcano has caused the volcanic smog, or "vog", to become quite an issue for the Hawaiian islands.
In fact, since the recent awakening of Halemaumau crater in March 2008, the emissions of harmful air pollutants have been times 10 times the normal amount.
Sulfur Dioxide, Carbon Dioxide and Hydrogen Fluoride are the most dangerous of the gases being released by Kilauea.
Vog is created when Sulfur Dioxide and other gases from the volcano mix, with and chemically react, with oxygen, moisture in the air, dust, and sunlight.
This mixture is called aerosol, which occurs when tiny particles of gas, liquid, and solid matter are suspended in the air.
The aerosol in vog is made up mostly of sulfuric acid and other sulfate compounds, however trace amounts of several toxic metals are also found in vog. These particular metals found in the vog are selenium, mercury, arsenic, and iridium.
The further you get from the volcano, say Kona, the more you find concentration of this aerosol in the vog.
However, near the summit the vog is thick with sulfur dioxide, and is more dangerous.
Also vog settles just below the inversion layer, or 6,000 ft altitude. The funny thing is that as you go below 6,000 ft it gets less as you approach sea level. The worst conditions are found right at 6,000 ft, making mauka Ocean view, one of the most affected residential areas.
Between Halemaumau's eruptions and Pu`u O`o's continuous flow into the ocean, it has caused the Hawaii Civil Defense to post approximately 25 emergency health advisories.
In fact, they have even evacuated the Hawaii Volcanoes National Park on more than one occasion, and they even went door to door in Kau encouraging people to leave their homes. The thickness of the vog is called the vog index.
Advisories are posted when conditions get unhealthy for the average person. This has been occurring when the tradewinds that disperse the vog slow, or even stop.
The map on the right shows the usual pattern for the tradewinds, which also explains why the South and West sides of the island have been affected the most.
Sulfur Dioxide poses the biggest threat to residents of the Big Island.
Sulfur Dioxide is a colorless gas with a pungent odor that can irritate the skin and the delicate tissues surrounding the eyes nose and throat.
Mostly it affects the upper respiratory tract.
1 ppm of sulfur dioxide can cause health problems.
When this happens, even the other islands start to feel the effects. You can not see more then a few hundred feet at times, let alone the horizon.
I talked to one man who said that one day in Pahala it was hard to make out the top of telephone poles.
I have seen it so bad in Ocean View that the sun almost disappeared. It appeared to be a red glow in the sky, like some kind of science fiction movie.
On the right is a picture of the vog in Kona at sunset, this is a good example of conditions in Kona lately.
Below is a list of things that are known to counter the affects of the vog.
1. Smoking or other lung irritants should be avoided. This is a great excuse to stop smoking!
2. Stay well hydrated. Warm fluids in particular seem to help with respiratory difficulties. Personally I have found Mamaki tea to be helpful, I have also heard that making a tea out of cayenne pepper tea is helpful.
3. If there are health advisories, do your best to not over exert yourself. In other words, don't do anything over and above normal activity.
4. If the vog gets real bad, stay inside with the windows closed. Kau usually has the most hazardous conditions, because it is right down wind from the volcano. Air conditioners and air purifiers are also known to help.
5. Finally if you are experiencing serious side effects from the vog, consider spending some time in a area where there is low vog levels, such as Kohala, and see if that helps. If it doesn't, then it might not be the vog that is causing the problem.
For more information on the Big Island Vog Index, follow this link
To go to our vog blog, and read what other people have posted, follow this link.
To go to our page on recent activity of Big Island volcanoes, follow this link