What a year for frostquakes (icequakes) also known as cryoseisms.
Chuck Herron heard the loud thud, then another and another. It sounded like someone was dropping big snowballs on the roof of his home.
As his neighbors in tiny Paris, Mo., huddled around televisions Sunday for the Super Bowl, many were startled by similar strange noises. Some even saw flashes of light and called 911.
Scientists say the community experienced a rare natural phenomenon known as a “frost quake,” which happens when moisture in the ground suddenly freezes and expands. If conditions are just right, the soil or bedrock breaks like a brittle frozen pipe, generating mysterious noises that range from an earthquake-like rumble to sharp cracking sounds sometimes mistaken for falling trees.
Experts say damage is rare but homeowners who experience a frost quake should check for foundation cracks and watch for damage to water and natural gas lines.
It’s been happening in Michigan, Ohio, Wisconsin, Indiana as well as Canada. The noises are said to sound like sonic booms or explosions that rattle the house. The few mentions of flashes of light in this and other cases is intriguing. The prevalence of frost quakes this year is likely due to the North American cold wave of this season, called the “polar vortex“.