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What drives climate change?

National Geographic basic explaination of climate change drivers.

FACT FILE What drives climate change?
Solar input
A third of the sun's energy is reflected back into space after hitting Earth's upper atmosphere, but two thirds gets through, driving Earth's weather engine.
The atmosphere
A delicate balance of gases gives Earth its livable temperature. Known as "greenhouse" gases because they trap heat inside the atmosphere, they send a portion of that heat back to Earth's surface. The gases include water vapor, carbon dioxide, methane and nitrous oxide.
The oceans
Covering two thirds of Earth, oceans are the key source of moisture in the air and they store heat efficiently, transporting it thousands of miles. The oceans and marine life also consume huge amounts of carbon dioxide.
The water cycle
Higher air temperatures can increase water evaporation and melting of ice. And while water vapor is the most potent greenhouse gas, clouds also affect evaporation, creating a cooling effect.
Clouds
They both cool Earth by reflecting solar energy and warm Earth by trapping heat being radiated up from the surface.
Ice and snow
The whiteness of ice and snow reflects heat out, cooling the planet. When ice melts into the sea, that drives heat from the ocean.
Land surfaces
Mountain ranges can block clouds, creating "dry" shadows downwind. Sloping land allows more water runoff, leaving the land and air drier. A tropical forest will soak up carbon dioxide, but once cleared for cattle ranching, the same land becomes a source of methane, a greenhouse gas.
Human influences
Humans might be magnifying warming by adding to the greenhouse gases naturally present in the atmosphere. Fuel use is the chief cause of rising carbon dioxide levels. On the other hand, humans create temporary, localized cooling effects through the use of aerosols, such as smoke and sulfates from industry, which reflect sunlight away from Earth.
Source: National Geographic; MSNBC

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