GGY 130 1st Edition Lecture 4Current LectureChapter 4: Insolation and Temperature  Energy, Heat, and Temperature Energy- capacity to do work  Heat- transfer of energy from one object to another due to a temperature difference  Temperature: expresses the degree of hotness or coldness  Energy Sources Incoming solar radiation (insolation) Radioactive decay of minerals  Hydrothermal vents Electromagnetic Radiation Waves travel at a speed of 300,000 kilometers per sec (speed of light) Takes over eight minutes for light from the sun to reach Earth Wavelength and Frequency  Wavelength: distance between successive crests  Frequency: number of crests that pass a fixe point per time unit  There is an inverse relationship between the wavelength and frequency (ie high frequency results in a short wavelength) Electromagnetic Radiation Spectrum  Peak intensity of the Sun’s energy is visible light  Radiation from the Sun- Shortwave (UV, visible, short infrared) Radiation from the Earth- Longwave (thermal infrared) These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. Solar Energy Journey Sun to Earth: interacts with the atmosphere = scattered and absorbed Reaches Earth: interacts with the ground surface = reflected, absorbed, and transmitted Earth back to the Atmosphere: interacts with the atmosphere = scattered and absorbed Thermometers Infrared (IR) thermometers measure the amount of emitted infrared  Hand/Soil and Air Thermometer determines the vertical temperature profile Electromagnetic Radiation Interactions with Matter 1) Radiation: process by which electromagnetic energy is emittedfrom an object  All objects with a temperature above 0*K (absolute 0) emit EMR  2) Absorption: energy process by which energy is absorbed and converted in other forms of energy  Most absorbing substances in the atmosphere are water vapor, carbon dioxide, ozone, O2, and nitrogen