Ice jams

Ice runs
River ice

Nature

Some rivers in the high latitudes of the northern hemisphere do not ice over completely in winter to form a stable ice cover, usually due to their high water velocities. Ice may be formed due to low temperatures, but it breaks away and large quantities move downstream, tending to damage bridge structures, producing ice jams and consequent flooding, particularly when such jams break. Ice moving in this way may causes much damage to hydroelectric installation intakes.

Incidence

Floods caused by ice jams and ice breaking up occur in the early spring. They often occur at constriction points such as at a sharp bend, gorge, bridge-crossing or any other physical obstacle. They may also occur where the gradient of a channel changes from steep to gentle, or at the point where a stream discharges into a lake. In Canada and Russia such floods typically occur when the ice and snow in the headwaters of northward flowing streams melt more rapidly than ice and snow in the lower reaches.

An analysis of the impact of climate warming on transportation in the MacKenzie Basin region of northern Canada found that there would be an increase of the open water (navigable) season on the MacKenzie River of 19-42 days, depending on the scenario used. This would favour an increase in shipping by barge, the least expensive method.

Claim

Ice jams pose a significant threat to communities, infrastructure, and ecosystems, making them a critical issue that demands urgent attention. These natural blockages can lead to devastating flooding, property damage, and even loss of life. As climate change alters weather patterns, the frequency and severity of ice jams are likely to increase. It is imperative that we prioritize research, prevention, and mitigation strategies to protect vulnerable areas and ensure public safety. Ignoring this problem is not an option.

Counter-claim

Ice jams, while occasionally disruptive, are largely overblown as a significant problem. They are natural phenomena that occur in specific conditions and often resolve themselves without intervention. The media sensationalizes these events, diverting attention from more pressing issues like climate change or infrastructure decay. Communities can adapt and mitigate risks without excessive alarm. In the grand scheme, ice jams are a minor inconvenience, not a critical concern demanding urgent action or resources.