Skip to main content
U.S. flag

An official website of the United States government

Kīlauea summit eruption in Halemaʻumaʻu crater - September 29, 2021

Detailed Description

The eruption that began today within Halemaʻumaʻu crater in Kīlauea’s summit caldera, within Hawai‘i Volcanoes National Park, is generating a vigorous plume of volcanic gas. The volcanic gas, which includes sulfur dioxide (SO2), interacts in the atmosphere with oxygen, moisture, dust, and sunlight over minutes to days and forms volcanic air pollution, or VOG, which can be transported downwind. Learn more about vog here: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/frequen…. USGS image. 

Sources/Usage

Public Domain.