Study suggests a looming effect of extreme freezing temperatures in the north – Frostquakes

A recent study has highlighted an emerging consequence of extreme freezing temperatures in northern regions—Frostquakes, also known as cryoseisms or ice quakes. These frostquakes, triggered by fluctuating weather patterns linked to climate change, were previously associated with heavy precipitation and cold waves. However, the study unveils a new factor in their origin: wetlands.

Traditionally, frostquakes occurred due to the freezing of water in the ground, most prevalent during extreme winter conditions when wet, snow-free ground freezes rapidly. Instances of frostquakes have been documented in various locations, including northern Finland in 2016, 2019, and 2022, as well as in Chicago (2019) and Ottawa (2022). Historically, roads and snow-cleared areas were prone to frostquakes. Still, the current study indicates that drainage channels and wetlands are now also vulnerable to these seismic events.

The research, conducted by the University of Oulu, Finland, and the Geological Survey of Finland (GTK), found that the uppermost frozen ground can fracture if the frozen layer’s thickness is around 5 cm or more. These ruptures can propagate deeper, posing risks to infrastructure like buildings, basements, pipelines, and roads.

The study specifically identified swamps, wetlands, and areas with high water tables as significant sources of frostquakes during the winter of 2022–2023 in Oulu, Finland. Seismic station networks in the region recorded ground tremors and unusual sounds reported by locals on days when the air temperature rapidly decreased.

The favorable conditions for frostquakes include temperatures dropping to more than -20°C at a rate of about one degree per hour. The presence of wetlands near seismic stations in Oulu played a crucial role in detecting the main sources of frostquakes.

Based on the insights gained from this study, researchers aim to develop a predictive system for frostquakes using soil analysis and satellite data. Such a system could help anticipate and mitigate the impact of these unique seismic events in northern regions affected by extreme cold temperatures.