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What Are the Primary Controls of Climate?

Earth's climate is a delicately balanced system of interacting elements powered by the sun. Atmospheric and ocean currents are in constant motion, warming the Earth from the sun's energy. Factors such as topography and vegetation along with atmospheric composition alter the Earth's climate. Mathematically speaking, weather is created by the difference between energy entering and leaving the climate system. As with all good things, our climate depends on several primary elements to function.

  1. The Sun

    • The sun is the source of most of the processes taking place in climate. It warms up the air, driving the jet streams that circle the Earth. Two jet streams, one in the Northern Hemisphere and one in the Southern, mix up the air masses. The hot air near the equator is mixed with the cold air from the poles, creating the changes in the climate.

    The Greenhouse Effect

    • The sun's energy hits the Earth and warms it up, and some of the energy is bounced back toward space. As the sun's reflected radiation travels back into the atmosphere, some gases absorb the radiation and bounce it back to the Earth, keeping the heat in. This process raises the average surface temperature to about 59 degree Fahrenheit. Without these gases, the Earth's average temperature would be around -0.4 degree Fahrenheit.

    The Oceans

    • The sun at the equator heats up the oceans. The currents of the oceans drive the warm water toward the poles, where the cold air cools the water down. The cooled water drops to the bottom of the ocean and flows back to the equator, then heats up again. This meridional overturning circulation process helps to keep the Earth warm.

    Temperature Zones

    • The sun shines down on the equator at a 90-degree angle to the Earth. At the poles, the sun shines on the ground at a reduced angle, resulting in less radiation heating the ice caps. The different temperature zones help to keep the flow of air moving and mixing the cooler and warmer air masses. The hotter equator climates also cause more evaporation from the ocean, creating the clouds that flow over cooler climates to supply rain.

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