Enter your current albedo, new albedo, and incoming solar radiation to see how a change in surface reflectivity affects reflected light, absorbed energy, and the estimated radiative forcing (warming or cooling effect). Choose a surface type for a quick reference albedo value, or enter a custom percentage.
Radiative Forcing (ΔF)
--
Currently Reflected
--
Currently Absorbed
--
New Reflected
--
New Absorbed
--
Total Energy Change Over Area
--
Effect
--
Albedo is the fraction of incoming solar radiation that a surface reflects back into the atmosphere. It is expressed as a percentage (or value between 0 and 1), where 0 means all light is absorbed and 100% means all light is reflected. Fresh snow has a very high albedo (~85%), while asphalt has a very low albedo (~4%).
When albedo decreases — for example when snow melts and reveals darker soil — more solar energy is absorbed by Earth's surface, causing warming. This is called radiative forcing. A positive radiative forcing value means more energy is being absorbed (warming effect), while a negative value means more energy is reflected (cooling effect).
Radiative forcing (ΔF) is the change in energy flux at Earth's surface or top of atmosphere caused by a climate driver. In this calculator it is calculated as the difference in absorbed solar radiation between the new and current surface state (new absorbed minus current absorbed), in W/m². Positive values indicate a warming tendency.
Earth's average albedo is approximately 30% (0.30), meaning about 30% of incoming solar radiation is reflected back to space. This is known as Earth's Bond albedo and is a result of contributions from clouds, ice, land surfaces, and oceans.
Forests, especially coniferous forests, have a relatively low albedo (~12%) compared to grasslands, farmland, or snow-covered ground. When forests are cleared and replaced with agricultural land or when snow-covered ground is revealed, the surface albedo can increase or decrease dramatically, directly impacting how much solar energy is absorbed.
This is known as the ice-albedo feedback loop. Ice and snow have very high albedo (~70–85%), so they reflect most sunlight. As temperatures rise, ice melts to expose darker ocean or soil surfaces with much lower albedo, which absorb more heat, causing further warming — a self-amplifying cycle that is one of the most powerful climate feedbacks.
Yes — this is the principle behind several proposed geoengineering strategies, such as painting rooftops white, using reflective crop varieties, or marine cloud brightening. By increasing the reflectivity of Earth's surface or atmosphere, less solar energy is absorbed and a cooling effect can be achieved.
Solar radiation and radiative forcing are expressed in watts per square metre (W/m²). If you enter a surface area in km², the total energy change is also shown in megawatts (MW). Albedo is expressed as a percentage (0–100%), where 100% represents a perfectly reflective surface.