A towering column of gas and ash from Kīlauea’s summit has once again turned parts of Hawaii’s famously clear skies into a hazardous haze, with a respiratory alert following reports that roughly 100,000 tons of toxic emissions were released during a 10 hour eruption. The blast, centered in the Halemaʻumaʻu crater, produced spectacular lava fountains but also a dense plume of sulfur dioxide and fine particles that can irritate lungs, trigger asthma, and aggravate heart and lung disease. Health officials are now warning that the lingering volcanic smog is as much a public health story as a geological one.
As the eruption cycle grinds on, the scale of gas output and the frequency of these episodes are forcing residents, visitors, and authorities to treat Kīlauea not just as a natural wonder but as a chronic air quality challenge. I see a community trying to balance daily life, tourism, and cultural connection to the volcano with the reality that each new burst of activity can send another wave of hazardous air across the islands.
The 10 hour eruption that filled Hawaii’s air with 100,000 tons of gas
The latest alarm was triggered after a summit outburst that lasted just under 10 hours and sent a towering plume of volcanic gases across Hawaii. Reporting on the event describes a Respiratory alert issued after the eruption choked the region with an estimated 100,000 tons of poison gas, a figure that underscores how much material a single episode can inject into the atmosphere. The blast, which unfolded on January 12, is part of a broader pattern of summit activity that has turned Halemaʻumaʻu into a near constant source of emissions.
Scientists tracking the summit sequence identify this outburst as part of Kīlauea’s episode 40, a phase of lava fountaining that has been documented in detail by 40 focused photo and video observations. Those records show lava jets reaching heights of about 800 feet inside the crater, a violent display that helps explain the sheer volume of gas lofted into the trade winds. The eruption’s location within Halemaʻumaʻu, a feature at the heart of Kīlauea, means emissions are funneled directly into the atmosphere above populated parts of the island.
What USGS data reveals about Kīlauea’s current eruptive cycle
To understand why this eruption produced such a heavy gas load, I look at the broader pattern of inflation and deflation at the summit that scientists have been tracking for months. According to ongoing volcano updates, the summit has cycled through repeated short-lived eruptions, each preceded by measurable ground swelling as magma accumulates. Since the end of episode 40, instruments at the UWD tiltmeter have recorded Since the end of that event, the UWD sensor has measured 8.8 m of inflationary tilt, a sign that magma is again pressurizing the system and that more gas rich eruptions are likely.
Formal alerts from the USGS, including a recent USGS Volcano Notice labeled DOI and issued through HVO, describe an Activity Summary that confirms Halema activity at the summit and notes that Episode 40 lava fountaining from the crater floor has been one of the most vigorous bursts in the current sequence. A separate Volcano Notice with the same DOI and HVO branding had earlier documented a pause in the ongoing Halema eruption, showing how quickly the system can shift from quiet to explosive. Together, these bulletins paint a picture of a volcano that is not in a single prolonged eruption but in a series of intense, gas heavy pulses.
From episode 40 to a looming 41st blast
The January 12 eruption did not come out of nowhere, it marked a milestone in a drumbeat of activity that local scientists have been counting carefully. Coverage of the event notes that Kilauea eruption starts and stops again, marking Kilauea episode 40, with The Hawaiian Volcano Observatory reporting that this Episode was one in a series of short lived but powerful bursts. Visual accounts describe how massive lava fountains surge towards the sky as volcano erupts in Hawaii, and that this eruption marked the volcano’s 40th eruptive episode, underscoring how routine yet dramatic these events have become.
Scientists and park managers are already looking ahead to the next phase. Reporting from Michelle Broder Van Dyke Hawaii Volcanoes National Park notes that Kilauea’s 41st episode is expected between Jan 20 and 25, with Michelle Broder Van writing that The Hawaiian Volcano Obs has signaled that another eruption could occur soon. A detailed January 13, 2026 reference map provides a Detailed Description of how the Kīlauea summit eruption within Halema crater that began on December 23 has reshaped the crater floor, and that evolving topography will influence how future lava and gas are released. Video compilations, including one produced with a synthesized text to video voiceover that credits Hawai Volcanoes National Park and notes that All images and video are courtesy the U.S. Geological Survey, show how quickly each new episode can transform the landscape.
How vog and sulfur dioxide are affecting health across the islands
For people living downwind, the most immediate concern is not the lava but the invisible mix of sulfur dioxide and fine particles that locals know as vog. Health officials in HILO have repeatedly warned that elevated volcanic gas emissions from Kīlauea can irritate eyes, nose, throat, and lungs, with The Hawai Department of Health, or DOH, urging residents and visitors to take precautions as HILO Hawai communities face higher levels of sulfur dioxide and particulate matter (PM2.5). A related advisory from The Hawai Department of Health, or DOH, encourages residents and visitors to access Hawai Air Quality Data on the Clean Air Branch website so they can track sulfur dioxide and PM2.5 from volcanic activity in The Hawai region in real time.
Officials have been explicit about who is most at risk. A statewide news release notes that Especially vulnerable people include Individuals with preexisting respiratory conditions such as asthma, bronchitis, and emphysema, as well as older adults, infants, and pregnant people, prompting the governor’s office to repeat that warning in a News Release urging caution with elevated volcanic gas emissions. Separate guidance from the health department stresses practical steps, advising residents to Do not smoke and avoid secondhand smoke, Drink plenty of fluids to avoid dehydration, and Use air purifiers that can reduce PM2.5, recommendations laid out in a detailed Drink and Use focused advisory. Those instructions are not abstract, they are a response to the kind of 100,000 tons gas events that can blanket communities for days.
Living with a restless volcano and recurring alerts
For island residents, the challenge is that Kīlauea’s gas output is not a one off crisis but a recurring feature of life. The Hawai Department of Health, or DOH, has already issued multiple advisories that urge caution with elevated volcanic gas emissions, including a DOH URGES CAUTION statement that highlights how intermittent eruptions can still produce sustained vog. A companion message from the governor’s office, framed as a News Release, reinforces that message and urges people to stay indoors when vog is thick, use air conditioning on recirculate, and coordinate with local emergency management officials. These repeated alerts reflect a recognition that even when lava is confined to the crater, gas can travel far beyond the park boundaries.
At the same time, scientists are refining their understanding of how each eruptive pulse feeds the gas problem. A detailed reference map labeled Detailed Description of the Halema summit eruption shows how new vents and lava ponds have opened within the crater since late December, creating fresh pathways for gas to escape. A separate set of Kīlauea volcano updates notes that since the end of episode 40, the UWD tiltmeter has recorded 8.8 m of inflationary tilt, with an increase of 2.0 microradians that matches rates observed during previous fountaining episodes. That pattern suggests the 100,000 tons gas event is unlikely to be the last, and that Hawaii will need to keep refining how it responds to each new respiratory alert.
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