CLIMATE

What is Climate

Climate: the average, year-after-year conditions of temperature, precipitation, winds, and clouds in an area

What is Microclimate?Microclimate: climate conditions within a small

area that differ from those in the surrounding area

• This is why is it cooler in a patch of trees than in an open field

Factors that Affect Temperature

• The main factors that influence temperature are latitude, altitude, distance from large bodies of water, and ocean currents.

Climate zones categorized by Latitude• Tropical zone: Near the equator, extends 23.5⁰ N

and S of the equator• Polar zone: 66.5 ⁰ to 90 ⁰N and S latitudes• Temperate zone: located between tropical and

polar zones

How can bodies of water affect temperature?

Marine climates: mild winters & cool summers (winds off the ocean prevent temperature extremes)

Where in the United States does this happen?Answer: West Coast areasContinental climates: cold winters & hot summersWhere in the United States does this happen?Answer: Mid-Central U.S.

The Seasons• The seasons are caused by the tilt of the Earth’s

axis as Earth Travels around the sun• The earth is tilted through the poles at an angle of

23.5 ⁰• The axis never changes – the location of the Earth

relative to the sun does; due to the rotation of the Earth

http://www.phschool.com/webcodes10/index.cfm?wcprefix=cfp&wcsuffix=5012&area=view&x=8&y=7Web code: cfp-5012

Climate Regions

The six main climate regions are:1. Tropical Rainy2. Dry3. Temperate Marine4. Temperate Continental5. Polar6. Highlands

Tropical Rainy

Tropical wet: always hot and humid with heavy rainfall

• Afternoon thunderstorms are common here• Example: Tropical Rain Forests• Tropical wet-and-dry: always hot, alternating

wet and dry seasons; heavy rainfall in wet season

• Example: savannas (tropical grasslands)

Dry ClimateArid – desert with little precipitationSemiarid – dry, but receives about 25 to 50 cm of

precipitation per year

Temperate Marine ClimateMarine West Coast – mild winters and cool

summers and rainy wintersHumid Subtropical – hot summers, cool wintersMediterranean – warm dry summers, rainy

winters

Temperate ContinentalHumid Continental – hot, humid summers and

cold winters with moderate precipitation year round

Subartic – short, cool summers and long cold winters; light precipitation, mainly in the summer

PolarTundra – always cold with a short, cool summerIce Cap – always cold, average temp at or below

freezing

Causes of Climate Change

• Earth’s position relative to the sun• Sun’s energy output (solar energy)• Volcanic eruptions• Continental drift – the movement of the continents

Possible Causes of Short Term Climate Change (pages 642-647)

• El Nino – warm surface water from the western Pacific moves east toward the coast of South America

• La Nina – surface waters in the eastern Pacific Ocean are colder than normal

• Global Warming – gradual increase in the temperature of the Earth’s atmosphere