What is the water cycle? - Earth and Environmental - Earth ...€¦ · Continuous movement of water...

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What is the water

cycle?

Continuous movement of

water from the atmosphere

to the earth’s surface and

back to the atmosphere

again.

Transpiration -

plants giving off

water vapor

Evaporation – liquid

water changing into

water vapor

Condensation: water vapor (gas) changes into

liquid water.

Precipitation: water falls from clouds to the

ground.

The underground water that

fills almost all the pores in

rock and sediment.

Makes up 90% of the

earth’s unfrozen freshwater

supply.

Aquifer: a body of rock sediment in

which large amounts of water can flow

and be stored.

Porosity: percentage of open spaces in rock.

Permeability: how easily water flows through

open spaces. (can water pass through or

not?)

Zone of Saturation: the layer of ground where all the pores are filled with water.◦ The upper surface of the

zone of saturation is called the water table.

Russia

Beginning of a river

Usually found in the mountains.

Runoff from mountains flows to lowest point.

Smaller rivers that feed into a big river.

More often found in mountains than on flat land.

Where the river flows into a larger body of water

Ex. a lake, ocean, another river.

Watershed – area that drains into a body of water

River Basin - A region of land that drains into a river system (contains many different watersheds).

Separates one river basin from the next.

Young river: v-shaped channel; steep sides

Mature river: u-shaped channel; more sloping sides; some meanders (bends)

Old river: flatter u-shaped channel; sloping sides; lots of meanders

Sediment is deposited in a stream

when there is a decrease in the

speed of the water.

Decreased slope (steeper--> faster)

Bed widening (more friction)

Obstruction (slows down when it goes

around rock, tree, bridge)

Sloping fan-shaped deposit of

sediments

When a stream goes from steep drop to flat

land.

Very slow moving water, leads to sediment

being deposited making flood plains fertile.

Curves in a river caused by an obstruction.

Erosion occurs on the outside of a bend.

Deposition occurs on the inside of a bend.

Crescent shaped body of water, when a

part of a meander is cut off from the river.

Buildup of sediments at the mouth of a river.

Water slows down as it empties into another

body of water.

Oceans and Ocean Circulation

70%!

96% PURE

WATER

4% dissolved elements:

Cl, Na, Mg S, Ca, K

A measure of dissolved solids in sea water

Number of grams of dissolved salts in 1 kilogram of water

Measured in parts per thousand (ppt)

Evaporation and freezing increases salinity

Density is the mass of a substance per unit volume (D=m/v)

Affected by two things:◦Salinity: dissolved solids make water more dense

◦Temperature: Cold water is more dense

Factors affecting Seawater density

high salinity=increase density

Low temp = increase density

*Tempereature has a greater influence

*Occurs at low latitudes. Thermocline is absent at high latitudes.

http://marinebio.org/oceans/temperature/

Nitrogen, Carbon dioxide, and oxygen are most abundant

CO2 dissolves most easily

Cold water holds more gases than warm water

Divided into 3 major oceans: the Atlantic, the Pacific, and the Indian Oceans

The term “sea” refers to smaller areas of the ocean that are partially surrounded by land.

Ex: Mediterranean and Caribbean.

Ocean water moves in giant streams called currents that flow like rivers at the surface or far below.

There are 2 types of currents:

◦ Surface

◦ Density

Move on the surface of the ocean

Driven by wind

1.Warm:

Flow away from the equator toward the poles

Because areas near the equator are warm

Example: Gulf Stream

2. Cold Flow toward the

equator away from the poles

Originate at the poles where the water is cold

Example: California current

Red are Warm Currents and

Black are cold currents

Surface Currents

Wind is the driving force behind the formation of surface currents.

2 sets of wind patterns involved in forming most surface currents.◦ Trade Winds – Blow toward the equator

◦ Westerlies – Blow away from the equator

Move beneath the surface of the ocean

Caused by differences in the density of water a.k.a.Thermohaline Circulation