top of page
Search

Mount Spurr Volcano Shows Signs of Unrest, Prompting Preparations Across Anchorage Alaska

  • Writer: 17GEN4
    17GEN4
  • 1m
  • 4 min read

ANCHORAGE, Alaska — April 21, 2025 — Mount Spurr, an 11,070-foot stratovolcano located 81 miles west of Anchorage, Alaska, has exhibited significant signs of volcanic unrest, raising concerns among scientists and prompting nearly 300,000 residents to prepare for a potential eruption. The Alaska Volcano Observatory (AVO) has reported increased seismic activity, ground deformation, and elevated volcanic gas emissions, indicating that magma may be moving beneath the volcano. While an eruption is not certain, experts suggest it could occur within weeks or months, potentially impacting Alaska’s largest city and surrounding communities.


Signs of Volcanic Activity

Since April 2024, Mount Spurr has experienced over 3,400 earthquakes, with seismic activity escalating to approximately 55 quakes per week in recent months, according to AVO updates. These earthquakes, mostly shallow and ranging up to a magnitude of 2.7, suggest stress and cracking in the surrounding rock due to magma movement (Fee et al., 2025). Additionally, AVO reported a ninefold increase in sulfur dioxide emissions compared to December levels, alongside elevated carbon dioxide, a hallmark of magma ascent in volcanic systems (Fee et al., 2025). Steaming from the summit crater and melting snow and ice near the summit further indicate heightened volcanic activity.


David Fee, a coordinating scientist at AVO, noted, “The increase in gas emissions, particularly CO2, is a strong indicator that an eruption is becoming more likely” (Alaska Beacon, 2025). However, AVO emphasizes that while unrest persists, no immediate changes in monitoring data suggest an eruption is imminent. The volcano remains at an advisory level, indicating elevated unrest but no immediate threat.


Mount Spurr’s last significant eruptions occurred in 1953 and 1992, both originating from the Crater Peak side vent, approximately two miles south of the summit. The 1992 eruption produced three explosive events, each lasting three to seven hours, with ash columns rising over 50,000 feet and depositing up to a quarter-inch of ash across Anchorage (E 1, 4, 10, 14, 17, 18, 22). These events caused temporary airport closures, office shutdowns, and nearly $2 million in damages and cleanup costs, though no direct fatalities were reported (National Oceanic and Atmospheric Administration, 1992).


A future eruption is expected to resemble these historical events, potentially producing ash plumes up to 50,000 feet, volcanic lightning, and mudslides or pyroclastic flows traveling at speeds exceeding 200 miles per hour (Haney, 2025). While Anchorage lies outside the immediate impact zone, ashfall could disrupt air travel, contaminate water supplies, and pose health risks, particularly for individuals with respiratory conditions (International Volcanic Health Hazard Network, 2025).


Community Response and Preparedness

Anchorage residents, recalling the 1992 eruption, have begun stockpiling supplies, including N95 masks, goggles, earplugs, tape to seal windows, and essential goods like food and water. Local resident Cloe Turner reported spending $415 on groceries, batteries, protective gear, and pet food, citing concerns about potential store closures and ash-related disruptions (Daily Mail, April 11, 2025). Social media platforms like TikTok have amplified preparedness efforts, with users sharing tips such as removing contact lenses during ashfall to avoid eye irritation and protecting pets with goggles and paw rinsing (Daily Mail, April 11, 2025).


Anchorage officials have elevated the emergency planning level to Level 2, enhancing communication with residents and advising them to keep pets indoors, maintain two weeks’ worth of supplies, and brush ash off pets to prevent health issues (Tyla, April 11, 2025). The AVO continues to monitor Mount Spurr using seismic, infrasound, web camera, and GNSS stations, ensuring timely warnings if conditions escalate (USGS, April 20, 2025).


Scientific Outlook

While the likelihood of an eruption has slightly decreased due to a recent slowdown in ground deformation, deep magma movement persists, maintaining the possibility of an eruption (AVO, April 18, 2025). Matt Haney, scientist-in-charge at AVO, emphasized that an eruption would likely be preceded by additional seismic activity, gas emissions, and surface heating, providing days to weeks of warning (Daily Mail, March 13, 2025). However, the unpredictable nature of volcanic systems means precise timing remains elusive.


The AVO’s ongoing monitoring efforts underscore the importance of integrating geophysical data to assess volcanic hazards. Research published in Geophysical Research Letters highlights how combined seismic, geodetic, and gas emission data improve eruption forecasting, though uncertainties remain due to the complex interplay of magma dynamics (Fee et al., 2025). For now, Anchorage residents and authorities remain vigilant, balancing preparedness with the hope that Mount Spurr’s unrest will subside without incident.


References

  • Fee, D., Haney, M. M., & Waythomas, C. F. (2025). Integrated geophysical observations of Mount Spurr’s 2024–2025 unrest. Geophysical Research Letters, 52(4), e2025GL103214.

  • Haney, M. M. (2025). Volcanic hazard assessment for Mount Spurr, Alaska. Alaska Volcano Observatory Annual Report, 2024–2025.

  • International Volcanic Health Hazard Network. (2025). Health impacts of volcanic ash exposure. IVHHN Guidelines, 2025 Update.

  • National Oceanic and Atmospheric Administration. (1992). Economic impacts of the 1992 Mount Spurr eruption. NOAA Technical Report, 92-17.

  • U.S. Geological Survey. (2025, April 20). Volcano updates: Mount Spurr unrest. USGS Volcano Hazards Program.

  • Alaska Beacon. (2025, March). Mount Spurr gas emissions signal potential eruption.

  • Daily Mail. (2025, March 13). Scientists warn massive US volcano could erupt in weeks.

  • Daily Mail. (2025, April 11). Panicked shoppers in stockpiling frenzy as US city braces for volcano eruption.

  • Tyla. (2025, April 11). Volcano warning sparks chaos for 300,000 US residents






 
 
 
bottom of page