Gas plume from erupting vent in Halema‘uma‘u blown northward by sou...

Vog concentrations in Hawai'i are primarily dependent on the amount of SO2 emitted from Kīlauea, the distance from the source vents, and the wind direction and speed on a given day. During trade wind conditions, areas southwest of Kīlauea and the leeward side of Hawai‘i are most frequently affected by vog. Most of the vog stays beneath an altitude of 6,000-8,000 feet above sea level, the usual height of the trade wind inversion. This layer of the atmosphere increases in temperature with altitude, inhibiting the rise of cooler, vog-laden air. When trade winds are absent, most often during winter months, the summit of Kīlauea, East Hawai‘i, the entire Island of Hawai‘i, or the entire state can be affected by vog.