Latin AmericaLatin America

Climate – Environmental Climate – Environmental GeographyGeography

GCU 122 – World Regional GeographyGCU 122 – World Regional Geography

Jason DonoghueJason Donoghue

Chandler-Gilbert Community CollegeChandler-Gilbert Community College

Controls of ClimateControls of ClimateLatin AmericaLatin America

• The different climatic regions of Latin America are influenced by the following factors:– Global atmospheric circulation

• Positions of the Intertropical Convergence Zone, and the sub-tropical high pressure zones.

• Location of major global wind belts

– Geological configurations• Highlands of the Andes mountains• Altitudinal Zonation

Global Atmospheric CirculationGlobal Atmospheric Circulation

• Rising air at the equator allows for an abundance of precipitation year round.

• The sub-tropical high is were you will find some of the drier savannah and desert regions.

Effects of Pressure ZonesEffects of Pressure Zones• Sub-Tropical Highs

• Equatorial Low

Global Wind BeltsGlobal Wind Belts

• Wind patterns coupled with the physical landscape have a significant impact on climate.– Two prime examples

• Atacama Desert• Gulf coast of “Middle

America”

Orographic EffectOrographic EffectAtacama DesertAtacama Desert

• Prevailing winds from the east are forced up by the Andes Mountains, and descends on the leeward side.– Creates a dry high pressure zone.

Orographic EffectOrographic EffectCaribbean Coast – Middle AmericaCaribbean Coast – Middle America

• Prevailing winds from the east, again and are forced up by the highlands, creating areas of low pressure– This leads to precipitation, and

the lush rain forests located here.

Vertical Climate ZonesVertical Climate Zones

• Middle and South America also experience areas where you may find several different climates in one area.– This is because of the highland regions, and

the fact that as you rise in altitude the temperature cools.

• For every 1000 feet up you lose 5.5º

Altitudinal ZonationMiddle & South America’s Vertical Climate Zones

SeaLevel

SeaLevel

2500’ 750 m

TIERRA CALIENTE(Hot Land)

Bananas, Cocoa, Sugar, Rice

Altitudinal ZonationMiddle & South America’s Vertical Climate Zones

6,000’ 1800 m

SeaLevel

2000’ 600 m

SeaLevel

TIERRA TEMPLADA (Temperate Land)

Coffee, Rice, Corn, Sugar

Altitudinal Zonation

SeaLevel

6,000’

2000’

2,000 m

600 m

SeaLevel

12,000’ 3,600 m

TIERRA FRIA(Cold Land)

Corn, Wheat, Potato

Altitudinal Zonation

12,000’ 3,600 m

SeaLevel

6,000’

2000’

2,000 m

600 m

SeaLevel

TIERRA HELADA(Frost Land)

Altitudinal Zonation

Climate ZonesClimate Zones

• Tropical Rainforest• Tropical or subtropical

desert• Tropical Savanna and

Grasslands.• Mid-latitude Grasslands• Mediterranean Climate• Marine West Coast

Climate• Highland Climates

Tropical Rain ForestTropical Rain Forest

• The equatorial zones of high temperatures, and rainfall provide conditions for the rapid growth of vegetation in the form of rain forests of the Amazon and Middle America.– The Amazon basin ranges

from 60 to 80 inches of rain per year.

Tropical or Subtropical DesertTropical or Subtropical Desert

• Warm and dry all year long.– Partially due to the subtropical

high pressure zones located in these regions.

• Air becomes warmer and drier over the tropics and sinks.

– For the Atacama Desert it lies in the rainshadow of the Andes Mountains

• Additionally the cold ocean currents that flow north along the west coast of South America do not allow the winds to absorb much moisture.

Tropical Savanna and GrasslandsTropical Savanna and Grasslands

• These areas are typically warm and have some sort of seasonal precipitation.– The seasonal precipitation

depends on shifts in global wind patterns and pressure belts that shift to the north in the June-August season and to the south in the November-February period.

• Brasilia, Brazil – Wet Season – Nov. to Feb.

– Moto Grasso Plateau• Caracas, Venezuela – Wet

Season – Jun. to Oct.– Llanos

• Caracas, Venezuela

• Llanos

Mid-Latitude GrasslandsMid-Latitude Grasslands

• This climate zone is characterized by cooler temperatures, and low or seasonal amounts of precipitation.– Buenos Aries,

Argentina– Patagonia and the

Pampas in Argentina

MediterraneanMediterranean

• Moderate temperatures with dry summers and wet winters.

• Confined to a small section of southern Chile.– This is due in part to the

ocean currents, wind patterns and the location of the Andes Mountains.

• Wind patterns shifting north in June results in a distinct wet season here, and a distinct dry season in winter.

Marine West CoastMarine West Coast

• Cooler and wet all year long.

• Much like the Mediterranean Climate this zone is found in a small area of southern Chile, and is controlled by the same factors.– The westerlies bring heavy

rains to the coast here, partially due to the orographic effect caused by the Andes Mountains.

HighlandHighland

• Typically cooler temperatures, but this is where altitudinal zonation comes into play.– Many different climate

types can actually be contained within this zone.

Natural Hazards and Environmental Natural Hazards and Environmental ConcernsConcerns

• Tectonic Activity– Volcanoes and Earthquakes

• Caribbean Wind Patterns– Abundance of Hurricanes

• El Nino– Changes in Wind/Water flow that has global

implications

• Deforestation of the Amazon– Destruction of the “lungs” of the planet

Tectonic PlatesTectonic Plates

Earthquakes and VolcanoesEarthquakes and Volcanoes

Mexico City - 1985Mexico City - 1985

• In 1985 a major earthquake struck Mexico City.– Killed as many as

10,000 people– Devastated downtown

buildings– City sits on an old lake

bed with sediments that act similar to liquids during an earthquake

Caribbean Wind PatternsCaribbean Wind Patterns

• Tradewinds out of the east in this part of the world cause the eastern coasts of Mexico, and countries in Middle America vulnerable to hurricanes.

Honduras - 1998Honduras - 1998

• Hurricane Mitch slammed in to Honduras and surrounding nations in late October of 1998.– Dumped a year’s worth of

rain in 48 hours.– Flash floods and mudslides

deforested slopes– Left nearly 10,000 dead,

and almost 20,000 missing.• Devastated the Honduran

capital of Tegucigalpa.

El NinoEl Nino

• El Nino is a significant reason why climate in Latin America is usually variable.– During an El Nino cycle

typically cool waters off the coast of Peru begin to warm.

– This is because there is a shift in the weather patterns that characterize the south Pacific.

• Usually we see wind patterns that force the warmer water towards Indonesia and during an El Nino year, this wind slackens, or shifts entirely, allowing the warm waters to flow back across the Pacific ultimately off the coast of Peru.

• Normal Cycle

• El Nino Cycle

Effects of El NinoEffects of El Nino

• Brings warmer and wetter winds to the coasts of Peru and Ecuador.– With this we see flooding

and mudslides.• Global Effects:

– Droughts in northeast Brazil

– Floods in southern Brazil and northern Mexico

– Fewer hurricanes due to wind pattern changes.

– Droughts and fires in Indonesia, South Africa, and Australia

Deforestation of the AmazonDeforestation of the Amazon

• In the 1970’s the Brazilian government began to focus on the development of the Amazon.– Along with this came the

beginning of large scale deforestation of the rain forest.

• Networks of roads were built.• Thousands of fires are set

each year to clear large sections of forest

• The rate of deforestation vary region by region based on how they are being cleared, and used.

– General agreement is that 15 percent of the Amazon basin has been cleared and the current rate is 50,000 sq miles a year.