We all tend to think of air pollution as something only humans cause. But one big source of air pollution is volcanoes. On the Big Island of Hawaii–the biggest of the five major islands that form the state of Hawaii–there are five volcanoes, and one of them is actively producing a lot of sulfur dioxide right now.

Sulfur dioxide combines with the water in the air to form a volcanic fog–called vog by some people–that tastes a bit unpleasant and which causes a haze in the air. Longterm, it can cause damage to people’s lungs, and to plants and animals. You can see the vog over the town of Kailua-Kona in this picture:

The view toward Kona through the vog

The view toward Kona through the vog: photo by Jay Torborg

Volcanoes are well known to cause global climate change. In the years following the eruption of Tambora in Indonesia, which took place in 1815, global climates were much cooler than average, partially because the dust from the volcano reduced the amount of sunlight reaching the earth’s surface.

More information about Hawaii’s volcanoes can be found at the United States Geological Survey website: Hawaii Volcanoes Observatory.