The Natural Climate Cycle
Climate Is Changed by Many Processes
Climate change may result from both natural and human causes. The importance of human causes has been increasing during the past few decades.
Causes
The major causes of climate change are described in the following sections.
CO2 and Other Greenhouse Gas Variations
Human Activity and Greenhouse Gas
Reducing Other Greenhouse Gases
Ocean Circulation
Volcanic Eruptions
Solar Variations
Orbital Variations
Land Use Changes
Amplifiers
Factors that can amplify or reduce the effect of the causes of change are known as "feedbacks." Some of the key feedbacks are described in the following sections. These feedbacks consist of interconnected processes in which a change in one leads to a change in another, which ultimately leads to further changes in the first.
Aerosols
Clouds
Water Vapor
Ice-Reflectivity
The effects of these causes and feedbacks can be seen in the climate changes that are in Historic Climate Changes and elsewhere throughout this web exhibition.
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