Role of Climate

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Local Conditions

• How would you describe your climate, or the average year after year conditions of temperature and precipitation where you live?

Does your area receive a great deal of precipitation-rain or

snow-or is your area very dry?

Questions• When does the area in which you live experience

the lowest temperatures?• Does the temp get below freezing• When does your area have the highest

temperatures?• How often does it rain where you live?• Is one season rainier than others• Does it snow where you live?• If so what is the heaviest snowfall you can

remember?• What are two factors that affect climate?

What is Climate?

• Weather-day-to day condition of the Earth’s atmosphere at a particular time and place.

• May be clear or sunny one day and cloudy and cold the next

• Climate- refers to average, year after year conditions of temperature and precipitation in a particular region

• Climate is caused by many factors including:

– Trapping of heat by the atmosphere

– Latitude

– Transport of heat by winds and ocean currents

– Amount of precipitation that results

– Shape and land elevation contribute to global climate patterns

• Energy of incoming sunlight drives Earth’s weather and helps determine climate

• Presence of certain gases in the atmosphere also has an effect on its temperature.

The Greenhouse Effect

• Carbon dioxide, methane, water vapor, and a few other atmospheric gases trap heat energy and maintain Earth’s temperature range.

• Greenhouse effect-natural situation in which heat is retained by a thin layer of greenhouse gases.

The Effect of Latitude on Climate

As a result of differences in latitude and thus the angle of heating, Earth has three main climate zones: – polar– temperate – tropical.

Polar Zones

• Cold areas where the sun's rays strike Earth at a very low angle.

• These zones are located in the areas around the North and South poles

– between 66.5° and 90° North and South latitudes.

Temperate Zones

• Sit between the polar zones and the tropics

• Temperate zones are more affected by the changing angle of the sun over the course of a year

• The climate in these zones ranges from hot to cold, depending on the season.

Tropical Zone

• Or tropics, is near the equator

• Located between 23.5° North and 23.5° South latitudes

• Receive direct or nearly direct sunlight year-round, making the climate almost always warm.

Heat Transport in the Biosphere

• The unequal heating of Earth's surface drives winds and ocean currents– transport heat throughout the biosphere

• Winds form because warm air tends to rise and cool air tends to sink– air that is heated near the equator rises