Glacial Ice Dams

Glaciers move consistently. The rate and how these glaciers change depends on the elements and surrounding environment. In the warmer summer months, glaciers melt more quickly and have a shorter time period for reforming. Much of the features we observe in the summer are affects of gravity, force, and elemental shifts.

During the winter, glaciers move much slower and have more time to accumulate than they have to melt. As we observe the melting and forming stages of glacier ice, we can simultaneously explore some of the unique features that are created during these transition periods.

What are Glacial Dams?

In simplicity, glacial dams can be characterized as ice blockages in meltwater. These floating ice formations flow along with the meltwater and gravity until reaching land features that cannot be easily moved through or around. This is where we see glacial dams start to have more nuanced features to them that accumulate to something much bigger.

Features of a Glacial Dam

Dams that are formed by moraine (rock deposits carried by glacier ice) can be dense and stable, and hold meltwater lakes for years. (NSIDC) Factors that contribute to this stability are the density and bonding of ice formations, turbidity of water, and gravity. Other glacial dams can be categorized as unstable, or as leaking glacial dams. Leaky ice formations allow meltwater to slowly drain into nearby rivers while reserving some of the cleanest water available to us.

Changes in Ice Formations

Glacial dams, a natural levee, changes state at different rates in relativity to the surround area. As our environments change across the globe we collectively become more observant of the attributes of these ice formation. And, the dynamics between land features that influence their flux state.

Glacial dams that are influenced by moraine walls have a more porous sedimentary composition to them. Scientists keep a keen eye on these. Once too much force presses on the rocky material, those porous sheets can burst quickly and without much warning.

Leaky glaciers can also lose their integrity with the the increase and force of meltwater. Ice dams that have gentle cascades of meltwater can burst these natural barriers and overflow lakes. So, these dams act as both a holding and release system.

Ice dams hold in pristine, fresh drinking water, and create water reserves. And, they have the ability to have an outburst flood. These are floods that have a significant impact on surrounding areas and have little to no warning time. Having a safe drainage system for these, amidst environmental changes, is quite important.

Effects and Acknowledgments

As scientist observe the changes in relation between the stability of ice and the increase in meltwater, people adapt to asses these risks. Some experts have tried to reinforce moraine walls as they gauge the stability of the wall. Others have even added drainage to leaky ice dams if a flood possible is predicted. This allows for natural formations to continue to reserve this fresh water, while still draining into rivers.

While glaciers are beautiful and enthralling, please leave any of this risk mitigation to the experts. While glaciers are inherently dangerous, there is still much to be explore and learn from these ice giants. And, get to witness the beauty of the natural world on a larger scale, while hopefully being able to learn more about our own worlds and how we can interact with abrupt changes.