Atmospheric Heating Notes

Atmosphere heated by our Sun Solar constant = gives our planet a constant amount of solar energy (sunlight) The sun emits different forms of energy depending on its wavelength (lambda). This is called the ‘solar spectrum’. Heat budget = balance between the amount of solar energy being absorbed by the Earth; and the amount of solar energy being reflected back into space. Differences in temperature on the earth are then accountable by the inclination of the Earth’s axis and unequal heating.

Atmosphere heated by our Sun

Conduction, Radiation and Convection – Earth’s Atmosphere Radiation is the transfer of thermal energy through space by electromagnetic waves (ex. x-rays, visible light, ultraviolet, or infrared) Matter is not required for the transfer of energy by radiation! waves. ALL objects (including you) emit radiant energy. Convection: Convection is the transfer of thermal energy by movement of molecules within a liquid or gas. The liquid or gas becomes less dense as it is heated. Conduction: Conduction is the transfer of thermal energy through direct contact. Conduction is heat transfer through the movement of molecules in solids.

Reflectivity, Scattering and Albedo

Reflectivity, Scattering and Albedo “Averaged over the entire planet, roughly 340 watts per square meter of energy from the Sun reach Earth. About one-third of that energy is reflected back into space, and the remaining 240 watts per square meter is absorbed by land, ocean, and atmosphere” Albedo (latin = white): Amount of sunlight reflected back into space 0.3 or 30% If all ice = .84 or 84% Factors into global warming Albedo becomes higher as an object gets lighter in shade