Watercycle Flashcards
What are the steps of the water cycle?
Evaporation- most take place over the ocean. When water vapour turns into liquid water.
Condensation- clouds form as water vapour cools. When the water vapour turns into liquid water.
Transpiration- plants release water to air through stems. The process of water moving through a plant and changing to water vapour before being released into the atmosphere.
Percipitation- water droplets in clouds become heavy and fall back to earth. The product of the condensation that falls from the sky.
This water can be stored on land as ice or snow or underground in aquifers (infiltration)
Infiltration- the process by which water enters a substance
What is runoff?
The draining away of water on the ground surface of an area of land, building, etc.
What are the factors that affect infiltration?
• slope of the land: steeper slopes do not give time for water to infiltrate the ground
• degree of saturation: the amount of water already in the ground
• porosity: the percentage of open space (pores and cracks) in the ground. Open space divided by total rock volume.
• permeability: a measure of how easily fluid flows through a porous solid. The permeability of the soul is the capacity of the soul to allow water the flow through.
• Capillary action: the action by which water moves against the downward pull of gravity ( can be caused by roots)
• vegetation: plants absorb water from the ground.
How much of earths water is freshwater and how much of it is available for living things?
2% of earth’s water is freshwater and only 1.2% is available for living things.
What is a watershed?
An area of land that drains into a particular body of water. Watersheds begin along a divide which is the highest point in the watershed. Watersheds are formed at higher elevations where water collects to form trickling streams and waterfalls.
How does water change as it flows through a watershed?
As rivers flatten out and widen, water warms and slows. Sediments and biodiversity increase. Headwaters are closer to the source and are cold and have low biodiversity.
What is an estuary?
Where the mouth of a freshwater river meets the ocean
How is the Chesapeake bay changing?
It’s the largest estuary in the US and one of the most productive estuaries in the world. Excess nutrients from agricultural fertilizers, runoff and wastewater dissolve into the bay causing poor water clarity and low dissolved oxygen.
What is groundwater?
Comes from precipitation that soaks into the ground and fills in tiny gaps between soil and sediments.
What is most groundwater used for?
Agriculture
What is the unsaturated zone and the water table?
The water table is the top of that saturation zone.
Unsaturated zone is the layers of rock and soil above the water table.
Where is groundwater located?
Groundwater is bordered on the top surface by the water table. This is the depth at which soil is saturated with water.
How do aquifers store water?
An aquifer consists of a layer of permeable, saturated rock and the slow-moving water in its pores. Wells can be dug into aquifers so water can be pumped out.
What’s an Aquitard?
An impermeable layer prevents water from flowing from one aquifer to another is called an aquitard.
Difference between an aquifer and an artesian well.
Confined aquifers recharge slowly because precipitation doesn’t reach them.
Artesian wells use the natural water pressure in a confined aquifer to bring water to the surface.
