GG101 Chapter Notes - Chapter 4: Solar Irradiance, Refraction, Advection
Document Summary
Solar energy that heats earth"s atmosphere & surface is unevenly distributed by latitude, and fluctuates seasonally. Transmission refers to the passage of shortwave & longwave energy through either the atmosphere or water. Atmospheric energy is composed of: shortwave radiation inputs (ultraviolet light, visible light, and near-infrared wavelengths, longwave radiation outputs (thermal infrared) that pass through the atmosphere by transmission. Insolation is the single external energy input driving the earth-atmosphere system. Radiation that arrives at earth"s surface is both direct & diffused (scattered by the atmosphere) Greater insolation occurs in low-latitude deserts worldwide because of frequently cloudless skies. Insolation encounters an increasing density of atmospheric gases as it travels toward the surface. Atmospheric gases, dust, cloud droplets, water vapour and pollutants physically interact with insolation. Scattering - gas molecules redirect radiation, changing the direction of the radiation"s movement without altering its wavelength. Scattering represents 7% of the earth"s reflectivity (aka albedo ) The shorter the wavelength, the greater the scattering.
