Surface Absorption and Reflection
Clouds are just one example of things that can change Earth's radiant energy balance. Snow and ice are other examples. If the surface of the Earth becomes cold enough, snow and ice will cover the surface and increase the amount of sunlight reflected back to space. So the amount of snow and ice on the Earth will change the global energy balance and therefore the global temperature. Conversely, as the planet warms, the amount of snow and ice on the surface will decrease, and so the planet will warm further—this is called a "positive feedback" because it tends to amplify climate change.

Less obvious, but still important, when vegetation is cleared from land surfaces (such as in deforestation or agricultural burning), the bare surface reflects more sunlight back to space and there is net cooling effect. But, there is also counter productive greenhouse gas effect that comes from deforestation and biomass burning—the release of carbon dioxide, as well as elimination of vegetation that would otherwise absorb carbon dioxide from the atmosphere during photosynthesis. Unfortunately, while deforestation/reforestation may take place on annual to decadal time scales, the lifetime of carbon dioxide in the atmosphere is 50 to more than 100 years. Consequently, the solar reflectance cooling and greenhouse gas warming due to biomass burning take place at very different time scales, leading to an initial cooling followed later by a warming trend.

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Why isn't Earth as hot as an oven?

Introduction

Clouds: A hot topic or are we made in the shade?

Surface Absorption and Reflection

Atmospheric Aerosols: Fossil Fuels and Biomass Burning

From Measurements to Climate Models

Related Data Sets:

Surface Temperature

Outgoing Longwave Radiation