(CN) – Spewing ash as far as 18 miles away, an increase in intensity of volcanic ash production at Hawaii’s Kilauea volcano caused the U.S. Geological Survey to upgrade its Aviation Warning Code from orange to red on Tuesday afternoon.
“Ash emission from the Kilauea summit vent will likely be variable with periods of increased and decreased intensity depending on the occurrence of rockfalls into the vent and other changes within the vent,” the latest observatory warning stated. “At any time, activity may become more explosive, increasing the intensity of ash production and producing ballistic projectiles near the vent.”
As of Tuesday, the top of the ash cloud was reported as high as 10,000 to 12,000 feet above sea level, according to National Weather Service radar and pilot reports.
“We’ve seen the waxing and waning (of the volcano). It seems that the system up at the summit has been what we call somewhat open, relieving that pressure,” said Michelle Coombs, a geologist with the Alaska Volcano Observatory, in a press briefing.
Ash has been rising nearly continuously from the vent and drifting downwind to the southwest. Ashfall and volcanic air pollution, known as VOG, has been reported in nearby communities about 18 miles downwind.
The Hawai’i County Civil Defense warned residents to limit their exposure outdoors due to the air quality.
“Condition RED means immediate danger to health so take action to limit further exposure. Severe conditions may exist such as choking and inability to breathe. This is a serious situation that affects the entire exposed population,” the agency said in a public notice.
While the newest eruptions are not threatening any homes or roads, they are creating loud booms and a fear of an explosive eruption at Halemaumau Crater. The threat of a crater explosion prompted officials to close most of Hawai’i Volcanoes National Park on Friday, one of the state’s most popular tourist destinations.
To date, some 37 structures have been destroyed, including 27 homes. Lava has covered more than 117 acres of land and at least nine roads are now impassable, according to Hawaii County Civil Defense officials.
Scientists predict activity will continue for some time with little relief in sight. For nearly two weeks lava has erupted daily from newly formed fissures – now at 21 outbreaks—since May 3 in the community of lower Puna. Six new fissures have opened in the last four days with one fissure producing lava slowly flowing toward the ocean at 20 yards per hour, according to local officials. This is a slowing from 100 yards per hour as it was tracked during the weekend.
Mandatory evacuations remain in place for about 2,000 people within two subdivisions of Leilani Estates and Lanipuna Gardens downrift of the eruptions.