hydrosphere: includes all the water at or near the surface of the earth.

most of it is believed to have been out gassed from the interior when the earth was younger

hydraulic cycle: all the water in the hydrosphere is caught up in this cycle: the major engine in the cycle is precipitation. and evaporation. 97% of water is in oceans.

100 million billion gallons move through the cycle every year

drainage basin: the region form which a stream draws its water.

discharge: the volume of water flowing past a given point (the product of channel cross section times velocity) cubic feet per sec.

Sediment Transport

bed load: heavier debris that is pushed along the bottom of a stream.

suspended load: consists of material that is light enough or fine enough to be suspended in the stream and be supported by the flowing water. clouds streams and gives them their muddy appearance

saltation: material of intermediate size that is carried along the stream bed in short hops.

dissolved load: some substances may be completely dissolved in the stream

load: the total amount of material carried by all these methods.

capacity: is the total measure of the total load material a stream can move

gradient: the degree of the angle of a stream bed it called its gradient

base level: the lowest elevation to which a stream can erode downward. could be a lake or ocean.

longitudinal profile: cross section taken at an angle perpendicular to a stream

well sorted: the material tends to be well sorted. with the material becoming finer as you move down stream

delta: a fan shaped pile of sediment formed when a stream empties into a still body of water

alluvial fan: a wedge shaped sediment deposit left when a tributary flows into a more slowly flowing river, or where a mountain stream flows into the desert.

meanders: bends or meanders in a stream that being to form because of irregularities in the channel than cause the velocity to change and the rate of erosion of deposition to change. curves form and tend to move down stream. the bars can move down stream at rates of hundreds of meters per year. but the norm is a few meters.. below 10

cut bank: the outside and down stream side of a curve in a river that is eroded more rapidly because of rapidly flowing water.

point bars: created on the inside of curves in streams because of deposits made by slowing water.

braiding: a process by which deposits in the center of channels causes the river to split into an intricate network of smaller streams this is called a braided stream.

flood plain: the area into which a stream spills over into during floods

oxbows: meanders will not lengthier indefinitely. during times of high discharge, the stream may cut a new short cut. leaving the elongated curves of the river isolated. when these hold water by their selves, they are called oxbow lakes.

flood: when a stream overflows its banks during times of high discharge it is called a flood.

when the water input exceeds the capacity to carry that water down stream, a flood results

when it rains some water may infiltrate the ground and percolate through soil and rocks at greater depths. some evaporates. but most water runs down hill. into streams and lakes

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stage: the elevation of a stream at any point is called its stage

crest: the maximum level of a stream during a given period of time

upstream floods: floods that affect only small localized areas.

downstream floods: floods that affect large systems and large drainage basins

hydrograph: a graph that plots the fluctuations in stream stage or discharge over time

flood frequency curve: a curve showing discharge as a function of recurrence over time for a particular stream

recurrence interval: describes on average, how often a flood of a given severity will occur

probability it the inverse of recurrence

peak lag time: the time between the precipitation event and the peak flood discharge

retention ponds: large basins that trap runoff from over flowing streams

Channelization: a general term for various human modifications of the stream channel itself that are intended to increase the velocity of water flow

levees: raised banks along a stream channel