Freshwater Flashcards
How much of Earths water is freshwater?
3%
How much of Earth’s freshwater is frozen?
2/3
What is the difference between alpine glaciers and ice sheets?
Alpine Glaciers- A glacier that forms in the mountains
Ice Sheets- A glacier that spreads over land in all directions
How much of Earth’s frozen water is in alpine glaciers and ice sheets?
Alpine Glaciers- 3%
Ice Sheets- 97%
Where are Earth’s two largest ice sheets?
Antarctica and Greenland
When did the last ice age end?
20,000 years ago
Under what glacial conditions do sea levels rise and fall?
The decreasing of glaciers
What is sea ice?
Ice that forms when sea ice freezes
Does sea ice change sea level?
No because the amount of sea ice is equivalent to the amount of water that it displaces
How do glaciers and sea ice affect climate?
Glaciers and sea ice keep surface and air temperatures low
What is an ice core?
Long columns of ice taken from glaciers
How is an ice core used to find evidence of climate change?
Ice core helps detect the amount of carbon dioxide in the air
What does the positive feedback loop cause by melting glaciers and sea ice?
By melting glaciers and sea ice the amount of energy absorbed from the sun increases
What is a stream?
A body of water that flows within a channel
How does turbulent water flow improve downstream water conditions?
It increases the oxygen content of the water making it healthier
Define watershed
An area of land that drains runoff into a particular stream, lake, or ocean
Define headwater
A tributary stream of a river forming part of its source
Define estuary
A coastal area where freshwater from rivers and streams mixes with freshwater
How do people affect their watershed?
By changing the direction in which their runoff flows
What is groundwater?
Water that generally lies below the ground
What is surface water?
Water that generally lies on the Earth’s suface
What is an auqifer?
An area of permeable sediment or rock that holds significant amounts of water
Describe the saturated and unsaturated zones in a watertable.
Unsaturated- The pores near Earth’s surface that contain a mixture of air and water
Saturated- Pores far beneath Earth’s surface filled with water
What is porosity?
A measure of rock’s ability to hold water
What is permeability?
The measure of water’s ability to flow through rock and sediment
In what direction does groundwater flow?
From higher elevation to lower elevation
What is a well?
A shaft sunk into the ground to obtain water, oil, or gas
What is a spring?
Places where ground water is exposed
What are wetlands?
An area of land that is saturated with water for part or all of the year
Why are wetlands important?
Because of habitat, flood control, erosion control, and filtration
What are people doing to wetlands?
Humans are draining them out and filling them up with soil for roads, buildings and other uses
