Tephra

Tephra Latest News

Kīlauea has been erupting episodically within Hawaiʻi Volcanoes National Park since December 23, 2024, and although lava flows remain confined to the caldera, tephra from lava fountains may impact downwind communities.

About Tephra

• Tephra, a volcanology term for ash, is small rock fragments ejected from a volcano into the atmosphere, which is then deposited around and downwind of the volcano. 
• The size of particles that fall out is largest near the volcano and gets progressively smaller further from the volcano. 
• Tephra produces a wide range of hazards. 
  • When the ejected material is in the atmosphere, it is electrically charged and often produces lightning. 
  • Several people have been killed by lightning from volcanic eruption clouds. 
  • Other hazards are produced when the ash is deposited on the ground.
  • Ash can disrupt electricity, television, radio, and telephone communication lines; bury roads and other manmade structures; damage machinery; start fires; and clog drainage and sewage systems. 
  • It kills crops, damages machinery, and is a hazard to aviators. 
  • Tephra is heavy – a significant accumulation on a rooftop could collapse a building. 
  • In addition, it often blocks out the sun, creating darkness and unnecessary panic.
  • Ash can produce poor visibility and cause respiratory problems.

Source: USGS

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