part 5

Why do we care about glaciers?

They are a source of freshwater, regulate seasons, contribute to sea level rise, and serve as climate change indicators.

What is the significance of glaciers as a global indicator?

They represent environmental health and influence various functions within ecosystems.

What can cause sea level rise according to glacier dynamics?

Melt all glaciers could result in a sea level rise of about 65 meters (200 feet).

Define a glacier.

A large mass of ice formed from the accumulation, compaction, and recrystallization of snow over many years.

What are the main types of glaciers?

Valley (or alpine) glaciers and continental glaciers (ice sheets).

What is the firn line in glacier terminology?

It is the critical boundary that separates the accumulation zone from the ablation zone.

What are the two main processes that define glacier dynamics?

Accumulation (building up of mass) and ablation (loss of mass through melting, sublimation, and calving).

Describe plucking in glacial erosion.

Plucking is when a glacier picks up and removes pieces of rock and sediment from the underlying bedrock as it moves.

What are glacial erratics?

Debris that has been transported by glacial ice and deposited in a location different from its origin.

List examples of glacial erosional features.

Striations, U-shaped valleys, cirques, tarns, horns, aretes, and roche moutonnée.

What is basal slip?

The process by which glaciers move over their bed due to the presence of water and gravitational force.

Define till in glaciology.

Unsorted glacial sediment deposited directly from melting glaciers.

What is a glacial crevasse?

A deep, vertical fracture or crack that forms in a glacier or ice sheet.

What role does isostatic rebound play in glacier dynamics?

It's the process of the crust moving upward after the weight of the ice is removed.

What are some examples of depositional features formed by glaciers?

Moraines, eskers, drumlins, kames, and kettle lakes.

What is glacial retreat?

Glacial retreat occurs when the rate of melting exceeds the rate of snowfall and accumulation, causing glaciers to shrink.

Describe the role of glaciers in the hydrological cycle.

Glaciers act as important reservoirs of freshwater, releasing water into rivers and lakes as they melt.

What impact do glaciers have on local ecosystems?

Glaciers create unique habitats and influence watershed dynamics, affecting flora and fauna dependent on glacial meltwater.

What is the relationship between glaciers and climate change?

Glaciers are sensitive indicators of climate change; their rapid melting signals rising global temperatures and shifting weather patterns.

How do human activities affect glaciers?

Human activities, such as greenhouse gas emissions and land use changes, can accelerate glacier melting and affect their dynamics.

List examples of glacial erosional features.

Striations, U-shaped valleys, cirques, tarns, horns, aretes, and roche moutonnée. Additionally, features such as fjords, hanging valleys, and streamlined valleys are also formed through glacial erosion.

What are some examples of depositional features formed by glaciers?

Some examples of depositional features formed by glaciers include moraines, eskers, drumlins, kames, kettle lakes, and outwash plains.

What is a moraine in glacial geology?

A moraine is a landform composed of accumulated debris (till) left by a glacier, often forming ridges along its sides or at its terminus.

What is an esker?

An esker is a long, winding ridge of stratified sand and gravel deposited by meltwater streams flowing beneath a glacier.

What is a drumlin?

A drumlin is an elongated hill formed by glacial deposition, typically showing a smooth, streamlined shape, indicative of the glacier's movement.

Define kettle lake in relation to glaciers.

A kettle lake is a body of water formed when a block of ice buried in glacial sediment melts, creating a depression that fills with water.

What is outwash in the context of glaciers?

Outwash refers to sediment that has been carried away from a glacier by meltwater and deposited in a fan or plain, typically composed of

What is glacial sediment?

Glacial sediment consists of materials such as rock fragments, silt, and clay that are transported and deposited by glaciers.

What are glacial till and its characteristics?

Glacial till is unsorted sediment deposited directly by a glacier, characterized by a mixture of particle sizes from clay to boulders.

What is an outwash plain?

An outwash plain is an area of sediment deposition formed by meltwater streams flowing from a glacier, typically featuring sorted sediments.

Describe the formation of a kame.

A kame is a hill or mound of sediment that accumulates in a depression on a glacier's surface and is deposited when the glacier melts.

Define esker, including where it is formed.

An esker is a long, winding ridge of stratified sand and gravel deposited by meltwater streams that flow beneath a glacier.

What are moraines and how are they categorized?

Moraines are accumulations of glacial debris; they are categorized into terminal moraines (at the glacier's end) and lateral moraines (along the sides).

What role do kettle lakes play in glacial sediment deposits?

Kettle lakes form when blocks of ice become buried in sediment and later melt, creating depressions that fill with water, influenced by glacial activity.

Explain the significance of drumlins in glacial environments.

Drumlins are elongated hills formed by glacial deposition