Climate TermsClimate Terms

Factors Affecting ClimateFactors Affecting Climate

A. Low Latitudes

(30° S. to 30° N)B. High Latitudes

(60-90° N, 60-90° S.)C. Arctic Circle

(66° N)

D. Antarctic Circle

(66° S)

E. Mid Latitudes (30-60°, N & S)

Factors Affecting ClimateFactors Affecting Climate

Latitude plays a major role in climate. The farther one gets from the Equator, the cooler the climate.

High elevations are generally cooler than the surrounding landscape. (The “rule of thumb” is 3.5 degrees for every 1,000 feet.)

Other factors that help determine climate are wind and water currents, recurring phenomena such as El Nino, and large landforms.

World Climate PatternsWorld Climate PatternsGeographers divide the world into major climate regions.

The major climate regions are tropical, dry, midlatitude, high latitude and highland climates. Each of these can be broken down into smaller categories.

Each climate region has its own characteristic natural vegetation.

Climate patterns change over time as a result of both natural processes and human activity.

Latitude, Elevation, and ClimateLatitude, Elevation, and Climate

Latitude and elevation affect the Latitude and elevation affect the angle of the sunangle of the sun’’s rays and s rays and temperatures on Earthtemperatures on Earth

Low latitudes include the Tropic of Low latitudes include the Tropic of Capricorn, the Equator, and the Capricorn, the Equator, and the Tropic of Cancer.Tropic of Cancer.

The EarthThe Earth’’s polar areas are s polar areas are considered the high latitudes.considered the high latitudes.

Latitude, Elevation, and Climate Latitude, Elevation, and Climate (cont.)(cont.)

Mid latitudes: Mid latitudes:

Between 30 degrees N and 60 degrees Between 30 degrees N and 60 degrees N in the Northern Hemisphere, and N in the Northern Hemisphere, and between 30 degrees S and 60 degrees between 30 degrees S and 60 degrees S in the Southern Hemisphere, are S in the Southern Hemisphere, are considered the mid latitudes.considered the mid latitudes.

The most variable weather is found The most variable weather is found here.here.

Elevation:Elevation:

At all latitudes, elevation influences At all latitudes, elevation influences climate because of the relationship climate because of the relationship between the elevation of a place and between the elevation of a place and its temperature.its temperature.

As elevation increases, temperature As elevation increases, temperature decreasesdecreases

The Influence of Elevation on Temperature

Why does thinner air retain less Why does thinner air retain less heat? heat?

A.A. It is more denseIt is more dense B.B. It is less denseIt is less dense

Winds and Ocean CurrentsWinds and Ocean Currents

Wind and water combine with the Wind and water combine with the effects of the sun to influence effects of the sun to influence EarthEarth’’s weather and climate.s weather and climate.

Wind Patterns:Wind Patterns:

– Wind blows because of temperature Wind blows because of temperature differences on Earthdifferences on Earth’’s surface, with s surface, with tropical air moving toward the Poles tropical air moving toward the Poles and polar air moving toward the and polar air moving toward the Equator.Equator.

Winds and Ocean CurrentsWinds and Ocean Currents

– Global winds blow in fairly constant Global winds blow in fairly constant patterns called prevailing winds.patterns called prevailing winds.

– The Coriolis effect causes prevailing The Coriolis effect causes prevailing winds to blow diagonally rather than winds to blow diagonally rather than along strict north-south or east-west along strict north-south or east-west directions.directions.

Winds and Ocean CurrentsWinds and Ocean Currents

The Horse Latitudes:The Horse Latitudes:

When sailors became stranded in the When sailors became stranded in the doldrums, they would lighten the doldrums, they would lighten the load of the ships, including livestock, load of the ships, including livestock, so that a light breeze could move so that a light breeze could move them.them.

These areas then became known as These areas then became known as the horse latitudes.the horse latitudes.

Ocean currents are caused by Ocean currents are caused by factors such as:factors such as:

the Earththe Earth’’s rotations rotation changes in air pressurechanges in air pressure differences in water temperaturedifferences in water temperature The Coriolis effect is observed in The Coriolis effect is observed in

ocean currents as well.ocean currents as well. Ocean currents affect climate in the Ocean currents affect climate in the

coastal lands along which they flow.coastal lands along which they flow.

Weather and Water CycleWeather and Water Cycle

– Wind and water work together to Wind and water work together to affect weather—driven by affect weather—driven by temperature, condensation creates temperature, condensation creates precipitationprecipitation

El Niño is a periodic change in the El Niño is a periodic change in the pattern of ocean currents, water pattern of ocean currents, water temperatures and weather in the temperatures and weather in the mid-Pacific region. It can influence mid-Pacific region. It can influence climates around the world.climates around the world.

El NiñoEl Niño

A periodic reversal of the pattern of A periodic reversal of the pattern of ocean currents and water ocean currents and water

QuestionQuestion

A periodic change in the pattern A periodic change in the pattern of ocean currents, water of ocean currents, water temperatures, and weather in the temperatures, and weather in the mid-Pacific region is known as mid-Pacific region is known as which term?which term?

A.A. DoldrumsDoldrums B.B. CurrentCurrent C.C. Prevailing WindsPrevailing Winds D.D. El NiñoEl Niño

QuestionQuestion

Which climate would you prefer Which climate would you prefer to live in? to live in?

A.A. Tropical climateTropical climate B.B. Dry climateDry climate C.C. Midlatitude climateMidlatitude climate

RegionsRegions

Geographers divide the Earth into Geographers divide the Earth into regions that have similar regions that have similar climates.climates.

Each of these divisions has its own Each of these divisions has its own characteristic soils and natural characteristic soils and natural vegetation.vegetation.

Climate RegionsClimate Regions

Climates are organized into five Climates are organized into five regions:regions:

– Tropical climates—these are found in Tropical climates—these are found in or near the low latitudes—the or near the low latitudes—the Tropics.Tropics.

Tropical wet Tropical wet Tropical dryTropical dry

More about ClimatesMore about Climates

– Dry climates—there are two types of Dry climates—there are two types of dry climates—the desert and the dry climates—the desert and the steppe—which occur in low latitudes steppe—which occur in low latitudes or midlatitudes.or midlatitudes.

– Midlatitude climates—this climate Midlatitude climates—this climate experiences variable weather experiences variable weather patterns and season changes that patterns and season changes that give rise to a variety of natural give rise to a variety of natural vegetation.vegetation.

Temperate climate regionsTemperate climate regions

There are four temperate climate There are four temperate climate regionsregions

Marine west coast climateMarine west coast climate MediterraneanMediterranean Humid subtropicalHumid subtropical Humid continentalHumid continental

High Latitude Climate RegionsHigh Latitude Climate Regions

High latitude climates—freezing High latitude climates—freezing temperatures are common throughout temperatures are common throughout the year because of the lack of direct the year because of the lack of direct sunlight.sunlight.

Three high altitude climate regions are:Three high altitude climate regions are:

Subarctic Subarctic Tundra Tundra Ice capIce cap

Rain ShadowRain Shadow

Warm air crosses the ocean and the Warm air crosses the ocean and the land picks up water vaporland picks up water vapor

1

Rain ShadowRain Shadow As the warm air filled with water vapor reaches As the warm air filled with water vapor reaches

UtahUtah’’s Mountains, climbs to go over mountain. air s Mountains, climbs to go over mountain. air rises, it cools and cannot hold as much water rises, it cools and cannot hold as much water vapor. Vapor condenses and falls as rain or snow vapor. Vapor condenses and falls as rain or snow on mountains.on mountains.

2

Rain ShadowRain Shadow

When air reaches the far side of the When air reaches the far side of the mountain it has already lost much of its mountain it has already lost much of its water vapor. The dry side of the mountain water vapor. The dry side of the mountain is called the rain shadow.is called the rain shadow.

3

Prevailing WindPrevailing Wind

Wind in a region that blows in a fairly Wind in a region that blows in a fairly constant directional patternconstant directional pattern

Coriolis EffectCoriolis Effect

The resulting diagonal movement, The resulting diagonal movement, either north or south, of prevailing either north or south, of prevailing winds caused by the Earthwinds caused by the Earth’’s rotations rotation

DoldrumsDoldrums

A frequently windless area near the A frequently windless area near the EquatorEquator

CurrentCurrent

Cold or warm stream of seawater Cold or warm stream of seawater that flows in the oceans, generally in that flows in the oceans, generally in a circular patterna circular pattern

WindwardWindward

Being in or facing the direction from Being in or facing the direction from which the wind is blowing which the wind is blowing

WindwardWindward

being in or facing the direction from being in or facing the direction from which the wind is blowingwhich the wind is blowing

LeewardLeeward

Being in or facing the direction Being in or facing the direction toward which the wind is blowing toward which the wind is blowing

Rain Shadow EffectRain Shadow Effect

Result of a process by which dry Result of a process by which dry areas develop on the leeward sides areas develop on the leeward sides of mountain rangesof mountain ranges

Natural VegetationNatural Vegetation

Plant life that grows in a certain area Plant life that grows in a certain area if people have not changed the if people have not changed the natural environment natural environment

OasisOasis

Small area in a desert where water Small area in a desert where water and vegetation are foundand vegetation are found

ConiferousConiferous

Referring to vegetation having cones Referring to vegetation having cones and needle-shaped leaves, including and needle-shaped leaves, including many evergreens, that keep their many evergreens, that keep their foliage throughout the winterfoliage throughout the winter

DeciduousDeciduous

Falling off or shed seasonally or Falling off or shed seasonally or periodically; trees such as oak and periodically; trees such as oak and maple which lose their leaves in maple which lose their leaves in autumn autumn

Mixed ForestMixed Forest

Forest with both coniferous and Forest with both coniferous and deciduous trees deciduous trees

PrairiePrairie

AAn inland grassland arean inland grassland area

PermafrostPermafrost

PPermanently frozen layer of soil ermanently frozen layer of soil beneath the surface of the ground beneath the surface of the ground

HypothesisHypothesis

A scientific explanation for an eventA scientific explanation for an event

SmogSmog

Haze caused by the interaction of Haze caused by the interaction of ultraviolet solar radiation with ultraviolet solar radiation with chemical fumes from automobile chemical fumes from automobile exhausts and other pollution sourcesexhausts and other pollution sources

Factors of ClimateFactors of Climate

LatitudeLatitude ElevationElevation ContinentalityContinentality LandformsLandforms Winds and currents (inc. El Nino)Winds and currents (inc. El Nino)