Spring ice produces dramatic sounds as early thaw begins

Early spring thaw is causing dramatic cracking and booming sounds from lake ice in eastern Finland, as reported by Finnish public broadcaster Yle.

Residents near Kuopio’s Kallavesi lake have reported loud noises—including rumbling, cracking, and grinding—coming from the ice in Pirttilahti bay each morning. The phenomenon occurs as sunlight warms the frozen surface after cold nights, creating temperature-induced stress in the thinning ice.

Yle meteorologist Henriikka Heikinoja explained that the sounds peak when temperature differences are sufficient and the ice is thin enough to react. The noises are most audible around 8:30 AM but fade as daytime warming reduces the ice’s tension.

A video recorded by Yle captures the eerie sounds of the shifting ice.