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Climates changesClimates changes

Natural processes that Natural processes that change climatechange climate

Volcanic eruptionsVolcanic eruptions

The presence of The presence of aerosols (volcanic aerosols (volcanic ash, dust, and ash, dust, and sulfur- based sulfur- based aerosols) in the air aerosols) in the air increases the increases the amount of solar amount of solar radiation that is radiation that is reflected back into reflected back into space. Earth lower space. Earth lower atmosphere to cool.atmosphere to cool.

Ocean circulationOcean circulation

The changes in The changes in ocean circulation ocean circulation also can result in also can result in short-terms short-terms climates climates fluctuations.fluctuations.

Solar activitySolar activity

When the sun is When the sun is most active, it most active, it contains dark contains dark blemishes called blemishes called sunspots. sunspots.

Earth MotionsEarth Motions

These geographic changes in These geographic changes in earth’s land and water bodies earth’s land and water bodies cause change in climate.cause change in climate.

Changes in the shape of earth’s Changes in the shape of earth’s orbit and the tilt of earth on its orbit and the tilt of earth on its axis are other earth motions that axis are other earth motions that affect global climates.affect global climates.

Human impact on Human impact on climate changesclimate changes Human activities have Human activities have

contributed and will contribute to contributed and will contribute to global climates change. Also global climates change. Also natural processes have certainly natural processes have certainly contributed to many climates contributed to many climates changes throughout earths 4.6-changes throughout earths 4.6-billion year history. billion year history.

The Greenhouse EffectThe Greenhouse Effect

The greenhouse The greenhouse effect is a natural effect is a natural warming of both warming of both earth’s lower earth’s lower atmosphere and atmosphere and earth’s surface. earth’s surface.

Global WarmingGlobal Warming

As A result of As A result of increases in increases in carbon dioxide carbon dioxide levels, as well as levels, as well as other green house other green house gases, Global gases, Global temperatures have temperatures have increased. This increased. This increase is called increase is called Global Warming.Global Warming.