Scientists Warn America's Most Dangerous Volcano Could Trigger Disaster Without Erupting
Alexis Thornton
2 hours agoMount Rainier has loomed over the Pacific Northwest for millennia, a snow-capped sentinel visible from Seattle on clear days. But geologists are not worried about lava. The threat they say could reshape communities across Washington State does not require an eruption at all.
What Makes Rainier America's Most Dangerous Volcano
The United States Geological Survey has designated Mount Rainier the most threatening volcano in the Cascades. At 14,411 feet above sea level, the mountain carries the largest glacial system on any peak in the contiguous United States, and its flanks have been weakened over thousands of years by hydrothermal activity, which slowly turns solid rock into something closer to soft clay. That combination of ice, water, and structurally compromised terrain makes Rainier uniquely vulnerable to catastrophic collapse.
When the mountain's slopes fail, the result is a lahar: a fast-moving slurry of water, volcanic rock, and sediment that travels down river valleys with almost no time for communities to respond. According to the USGS volcanic hazards assessment for Mount Rainier, lahars rank above lava flows, ash fall, and pyroclastic surges as the single greatest hazard the volcano poses to the surrounding region.