The Hydrologic Cycle
Describe where water is present at and near Earth's surface.
Water is in lakes, streams, glaciers, groundwater, oceans, & the atmosphere.
Explain why water in large deep streams moves more rapidly than water in small, rocky streams.
A deep, wide stream has a smooth bed with less resistance allowing for higher velocity.
A small, rocky stream has a lot of turbulence due to friction and moves more slowly.
Describe how oxbow lakes form along a meandering stream.
Oxbow lakes form when erosion occurs on outer edges of curves in streams. The necks meander and become narrower until they break away and form an oxbow lake.
What is the source of all groundwater.
Groundwater comes from precipitation.
What is the source of the stream that leads to the pond on the GCA campus?
The stream is fed by an underground spring.
What is the energy source for moving water through the hydrologic cycle?
The hydrologic cycle is powered by the sun.
Describe factors that influence the shape of a delta.
A delta is accumulated sediments. The water currents cause the delta to grow farther out and the river changes course to find a shorter path to sea.
Name two human activities that cause flooding.
Humans can cause flooding by dam failures and urban growth (concrete pavement).
What is the difference between porosity and permeability?
Porosity is the percentage of pore spaces in rock or sediment.
Permeability is the measure of ability for water to move through rock or sediment.
What percent is stored in the glaciers of Antarctica and Greenland?
3% of the Earth's water is stored in glaciers.
Name the three drainage patterns of streams.
The three drainage patterns of streams are dendritic, radial, and trellis.
Name three causes of floods.
Floods can be caused by heavy rain, rapid snowmelt, and human activities.
What happens when more water is pumped from an aquifer than is refilled by rain?
The aquifer dries up.
Plants release water into the atmosphere through transpiration.
Transpiration is related to what process?
Transpiration is related to photosynthesis.
Explain the cause of turbulence in streams.
Turbulance is caused by friction with the edges & bottom of a stream. The water flow slows & makes a swirling motion.
Describe two ways engineers can prevent flooding.
Engineers construct artificial levees and dams to keep floodwater out of a community. New parking lots need retention basins to collect water.
Describe two changes we made when visiting the stream on campus.
We stirred the water causing suspension of sediments.
We created a dam which slowed the velocity.
We removed a dam which increased the velocity.
Name and describe the 5 main processes of the hydrologic cycle. (It is important to be able to answer this question with detail.)
Water evaporates in oceans & other water bodies.
In condensation, water molecules cool, stick together, & form clouds.
The droplets in clouds drop as precipitation.
The water infiltrates the ground as groundwater.
Plants capture water & release it to the atmosphere through transpiration.
A dissolved load is made up of substances that dissolve such as calcium & bicarbonate ions from limestone.
A suspended load is made up of small particles of clay, silt, or sand and is held up by turbulence. It is evident by the muddy appearance of the water.
A bed load is sediments that are too coarse to suspend like gravel and instead are moved along the bottom of the stream.
Meandering streams wander from one side of a valley to another.
Braided streams are many small channels separated by small islands.
What is so important about the Mississippi River that engineers work all the time to maintain the same flow and direction?
The Mississippi River supports a multi-billion dollar shipping industry, providing thousands of related jobs. It's one of the greatest water highways on earth, carrying commerce and food for the world.