Supraglacial lakes

Definition

Supraglacial lakes are bodies of water that form on the surface of glaciers and ice sheets, typically during warmer months as melting occurs. These lakes are significant indicators of climate change, as their formation and dynamics can influence glacier stability, melt rates, and overall mass loss. The presence of supraglacial lakes can also affect the flow of glaciers by altering their hydrology and contributing to the melting of the ice beneath them.

5 Must Know Facts For Your Next Test

1. Supraglacial lakes often appear during the summer months when temperatures rise and cause surface melting on glaciers.
2. These lakes can vary in size from small ponds to large bodies of water covering several square kilometers.
3. Supraglacial lakes can drain quickly, leading to dramatic changes in glacier dynamics by allowing water to reach the base of the glacier, potentially increasing sliding rates.
4. The formation of these lakes has been observed to correlate with increased rates of ice melt, contributing to sea level rise.
5. Recent studies show that the number and size of supraglacial lakes have increased significantly in response to global warming.

Review Questions

• How do supraglacial lakes impact glacier dynamics and stability?
  • Supraglacial lakes significantly affect glacier dynamics and stability by altering how water flows within and beneath glaciers. When these lakes form, they can create pressure that leads to increased melting at the glacier's base. This can enhance sliding rates and may contribute to overall glacier acceleration. Additionally, if these lakes drain suddenly, it can lead to rapid changes in glacier movement and potentially destabilize the ice.
• Discuss the relationship between supraglacial lakes and climate change.
  • Supraglacial lakes serve as key indicators of climate change, as their formation is largely driven by rising temperatures that cause increased surface melting on glaciers. The number and size of these lakes have been observed to increase as global temperatures rise, which not only affects local hydrology but also contributes to overall ice loss from glaciers. Monitoring these lakes provides valuable insights into how climate change is influencing glacial systems and sea level rise.
• Evaluate the potential implications of increased supraglacial lake formation on global sea levels.
  • Increased formation of supraglacial lakes could have significant implications for global sea levels due to their direct link to accelerated ice melt. As these lakes form and drain, they not only increase the rate at which glaciers lose mass but also enhance the flow of meltwater into oceans. This contributes to rising sea levels, posing risks to coastal communities worldwide. Understanding this dynamic is crucial for predicting future impacts of climate change on global sea levels.

Related terms

Glacier Dynamics: The study of the movement and flow of glaciers, including factors that influence their speed, melting, and interaction with surrounding environments.

Albedo Effect: The measure of how much light that hits a surface is reflected without being absorbed, influencing surface temperatures; darker surfaces, like water in supraglacial lakes, absorb more heat than ice.

Ice Sheet Mass Balance: The difference between the accumulation of snow and ice on an ice sheet and the loss of ice through melting or calving, which is crucial for understanding changes in ice sheets over time.