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 into the

atmosphere.

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 in which large

amounts of water can flow and be

stored.

Porosity: percentage of open spaces in rock.

◦ Determined by :

◦ Sorting: well-sorted- equal sized = more

porous

◦ Poorly sorted-unequal sized = less porous

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 (stream, river etc.)

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

Separates one river basin from the next.

The course of the water in a river or stream.

The volume of water flowing past a certain point in a given unit of time.

Usually measured in cubic meters per second (m3/s).

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)

Can create landforms or change the river

valley in the following ways:

Sloping fan-shaped deposit of sediments

Occurs where a stream descending a steep

slope flat land.

Part of the valley floor covered with water

during a flood.

Sediment is deposited making flood plains

fertile.

Raised river banks caused by flooding.

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 resulting

when a part of a meander is cut off and

abandoned by the river.

Buildup of sediments at the mouth of a river.

Occurs because the 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

Salinity–increase in salinityincreases density

Temperture

–decrease in tempincrease density

*Tempereature has a greater influence

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

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

Nitrogen (N2), Carbon dioxide (CO2), and oxygen (O2) are the most abundant

CO2 dissolves most easily

Cold water holds more dissolved gases than warm water

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

Has the longest distance North to South

Covers 30% of surface of the Earth

Mostly in the Southern Hemisphere

The Arctic and the Southern 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

Only affect the upper surface of the water.

1.Warm:

Flow away from the equator on the west sides of ocean basins

Because areas near the equator are warm

Example: Gulf Stream

2. Cold Flow toward the

equator on the east sides of ocean basins

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

Trade winds and Westerlies

Five Major Ocean Gyres

1. North Pacific Gyre

2. South Pacific Gyre

3. North Atlantic Gyre

4. South Atlantic Gyre

5. Indian Ocean Gyre

Western side of ocean has warm currents traveling from equator

Eastern side of ocean has cool currents moving toward equator

Move beneath the surface of the ocean

Caused by differences in the density of water due to its different temperatures and salinities

a.k.a.Thermohaline Circulation

Zone of rapid temperature changeWarmer water on top of layer

Colder, denser on bottom of layer

Begins at the poles where cold dense water sinks.

Warmer water moves in to take its place creating a current.

This drives the “global conveyer belt”

Process moves very slowly

One section on the “global conveyer belt”make take 1,000 years to fully cycle through the ocean!!

Crucial to the base of the world's food chain.

Adds CO2 and nutrients to surface waters by carrying them deeper in the ocean where those elements are abundant.

◦ This enables the growth of algae and seaweed that ultimately support all forms of life.

Helps to regulate temperatures