What is the cryosphere primarily composed of?
- Continental ice sheets
- Snow
- Sea ice
- Permafrost
Ice particles in clouds are not considered part of the cryosphere.
How does the melting of permafrost affect the atmosphere?
Releases greenhouse gases
This contributes to climate change.
What is the albedo effect in relation to snow cover?
High reflectivity of fresh snow reduces heat absorption
Fresh snow has an albedo of 80-90%.
Define permafrost.
Permanently frozen ground that remains at or below 0ºC for 2 years or more
Ice doesn’t have to be present for permafrost to exist.
What happens to snow as it ages?
- Ice crystals become more spherical
- More closely packed
- Reduced albedo and insulating properties
This affects the snow’s interaction with the climate system.
What are the two components of a glacier’s downslope movement?
- Plastic deformation
- Basal sliding
Basal sliding occurs when the glacier is not frozen to the bed.
What is the triple point of water?
Water exists in all three phases: solid, liquid, and gas
This is a specific condition where all three states can coexist.
What is the critical point of water?
No clear distinction between liquid and gas at high temperature and pressure
At this state, liquid water and vapor become indistinguishable.
What is the process of sublimation?
Water transforms directly from ice to vapor
This occurs under specific pressure and temperature conditions.
What is the significance of glacier ice in the Earth system?
- Low permeability
- Ability to flow under its own weight
These characteristics make glaciers important for understanding climate dynamics.
What is the difference between how glaciers on land grow thicker compared to glaciers in the ocean?
Glaciers on land accumulate ice at the surface; sea ice grows from the bottom
This distinction affects their formation and characteristics.
What is the ice-albedo feedback?
Temperature change causes changes in ice cover and surface albedo, further modifying temperature
This is a positive feedback mechanism.
What is the Northern Hemisphere snow cover like?
Varies from summer to winter, larger coverage in winter
Snow has high albedo, affecting regional energy balance.
What are the two types of glaciers?
- Mountain (or alpine) glaciers
- Continental glaciers
Mountain glaciers are found in mountainous regions, while continental glaciers cover larger areas.
What is the active layer of permafrost?
The upper layer that freezes in winter and thaws in summer
It is distinct from the permanently frozen ground below.
What is the process of snow formation?
Ice crystals form in clouds from water vapor, grow by deposition
Ice forms directly from vapor rather than freezing liquid water.
