What Happens to Insolation? Intro to Physical Geography
Energy Basics Energy Pathways and Principles Shortwave energy in from the Sun (ultraviolet, visible light, and near-infrared) Longwave energy out from Earth (thermal infrared) Transmission The passage of energy through atmosphere or water Insolation input All radiation received at Earth’s surface – direct and indirect
What happens to insolation? Scattering (diffuse radiation) Changing direction of light’s movement, without altering its wavelengths Rayleigh scattering makes our skies look blue
WavelengthsBecause blue lighthas a shorterwavelength itscatters more easily.Image from Wavelength image fromhttp://missionscience.nasa.gov/ems/09_visible Universe by Freedmanlight.html and Kaufmann.
What Happens to Insolation? Refraction Change in speed and direction of light as insolation travels from space through the atmosphere Examples: Rainbows and mirages
What happens to insolation? Some energy is reflected without being absorbed So we need to think about albedo (how reflective a surface is) Clouds and aerosols have unpredictable albedos What types of surfaces are most reflective? What types of surfaces absorb more energy?
What happens to energy that reaches the surface? Absorption – the assimilation of radiation by molecules of matter and conversion to different kinds of energy.• Heat is energy produced by the motion of atoms and molecules.• Heat flows from a region of higher temperature to a region of colder temperature, but not the other way around.• Four types of heat transfer: • conduction, convection, advection, and radiation.