Glaciers and Their Dynamics

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Questions and Answers

What defines an unconfined aquifer?

Contains high hydrostatic pressure

Always results in free-flowing water

Bounded above and below by impermeable rock

Has a water table and direct connection to the surface (correct)

In a meandering stream, where is the sediment likely to be deposited?

On the inside of meanders, forming point bars (correct)

In areas of low density sediment

At the point of highest stream velocity

Along the cut banks

What is the relationship between porosity and permeability?

Porosity measures the volume of open pore spaces while permeability measures fluid movement (correct)

Higher porosity automatically means higher permeability

Both properties are independent of each other

Permeability is defined as the total volume of rocks

Which layer of the atmosphere is referred to as the 'weather layer'?

Troposphere Signup and view all the answers

Which type of aquifer can cause water to rise above the top of the aquifer?

Artesian aquifer Signup and view all the answers

Which zone of a glacier is characterized by net mass gain?

Accumulation zone Signup and view all the answers

What process occurs when meltwater reduces friction allowing the glacier to slide?

Basal sliding Signup and view all the answers

What is the term for sediment deposited directly from ice?

Till Signup and view all the answers

Which type of glacier is specifically described as the largest on Earth and covers large areas of land?

Continental glacier Signup and view all the answers

What is the equilibrium line in a glacier?

The point where accumulation equals melting Signup and view all the answers

What type of stream flows year-round and is sustained by base flow?

Perennial stream Signup and view all the answers

Which type of load includes the largest materials dragged along the bottom of a stream?

Bedload Signup and view all the answers

Which of the following holds the largest percentage of Earth's fresh water in frozen form?

Glaciers Signup and view all the answers

What is a notable feature of the stratosphere?

Contains most of the atmosphere's ozone Signup and view all the answers

Which layer of the atmosphere absorbs ultraviolet solar energy?

Thermosphere Signup and view all the answers

What happens to temperature in the troposphere with increasing altitude?

It decreases Signup and view all the answers

What is the primary role of the ozone layer?

It absorbs harmful ultraviolet radiation Signup and view all the answers

Which factor influences wind patterns in the atmosphere?

Temperature differences Signup and view all the answers

What is Earth's average albedo?

30% Signup and view all the answers

Which process is NOT a method of heat transfer in the atmosphere?

Evaporation Signup and view all the answers

Why is ozone concentration higher at the poles?

Due to seasonal weather patterns Signup and view all the answers

Study Notes

Glaciers

Glaciers are bodies of ice that show evidence of movement due to their weight.
Accumulation zone: Area of net mass gain from snowfall, typically at the glacier's highest point.
Ablation zone: Area of net loss where ice and old snow are exposed.
Equilibrium line: Where accumulation equals melting.
Glacial movement is driven by internal flow (due to weight and ice crystal structure) and basal sliding (meltwater reducing friction).

Glacial Erosion and Deposits

Glacial drift: All sediment deposited by glacial erosion.
Till: Unsorted glacial drift deposited directly from ice.
Moraines: Till deposits with various forms (e.g., ground, terminal, lateral, medial).

Types of Glaciers

Continental glaciers (ice sheets): Largest glaciers, covering vast land areas, including Greenland and Antarctica.
Mountain glaciers: Alpine, cirque, valley, fjord, and piedmont glaciers.

Hydrologic Cycle

Water Distribution: Oceans contain most water (97.5%), while polar ice sheets hold 74% of fresh water. Groundwater is a significant reservoir of unfrozen fresh water.
Streams: Ephemeral streams flow only after rainfall, perennial streams flow year-round.
Stream flow: Consists of storm flow (from precipitation) and base flow (from groundwater).
Load Types: Bedload (large material dragged along the bottom), suspended load (fine material within the water), and dissolved load (ions from rock and organic matter).
Particle Movement: Velocity affects sediment distribution (lowest velocity along inside meanders, forming point bars, highest along outside meanders, creating cut banks).
Aquifer systems: Unconfined (water table connection) and Confined (bounded by impermeable rock, with artesian aquifers having high pressure for free-flowing water).

Porosity and Permeability

Porosity: Percentage of open spaces in rock.
Permeability: How easily fluids pass through rock.
Both determine water storage and movement in rocks.
Wells in unconfined aquifers have water levels equalling the water table.

Atmospheric Layers

The troposphere is the lowest layer, extending from Earth's surface to about 9 km at the poles and 12 km at the equator. Temperature decreases with altitude. This is where weather phenomena occur.
Stratosphere: Temperature increases with altitude, mostly stable. Ozone is mainly found here, absorbing UV radiation.
Mesosphere: Does not absorb solar energy.
Thermosphere: Contains minimal gases, absorbing short-wavelength solar energy.

Temperature Changes in the Atmosphere

Temperature variations are complex, with temperature decreasing with altitude in the troposphere (lapse rate) and inversions (temperature increasing) in the stratosphere.
Changes create distinct layers.

Ozone Layer

Located in the stratosphere.
Absorbs ultraviolet (UV) radiation, protecting life on Earth.
Ozone concentration is higher at the poles due to seasonal patterns and atmospheric circulation.

Pressure and Wind

Air moves from high to low pressure.
Wind patterns are influenced by temperature differences, the Earth's rotation (Coriolis effect), and topography.
Global wind patterns form distinct circulation cells (Hadley, Ferrel, and Polar cells).

Albedo

Reflectivity of Earth's surface.
Average albedo is 30%.
Higher at the poles due to ice cover.
Oceans have lower albedo when the sun is directly overhead.

Heat Transfer in the Atmosphere

Heat is transferred by convection (vertical air movement due to temperature differences), conduction (direct transfer between molecules), and radiation (energy transfer through electromagnetic waves).

Carbon Dioxide Cycle

CO2 is a greenhouse gas, absorbing and re-emitting infrared radiation.
Oceans play a role in absorbing atmospheric CO2 and regulating its concentrations.

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Description

This quiz covers the essential aspects of glaciers, including their types, movement, and the processes of glacial erosion and deposits. Test your knowledge on glacial features such as moraines and the hydrologic cycle associated with these massive ice bodies.