Lecture 5Outline of Last Lecture I. The Electromagnetic SpectrumII. Electromagnetic WavesIII. Radiation and TemperatureIV. Solar SpectrumV. Radiation and ColorVI. Radiation BudgetVII. Radiation and AtmosphereVIII. Greenhouse EffectIX. Why is the Sky Blue?Outline of Current Lecture X. Earth’s OrbitXI. Earth’s AxisXII. The SeasonsXIII. Angle of SunXIV. Seasonal TemperatureXV. Controls of TemperatureXVI. Daily High TemperaturesXVII. Nocturnal CoolingXVIII. The Role of CloudsCurrent LectureXIX. Earth’s Orbita. Earth orbits around the suni. orbit is an ellipse (slightly egg shaped)ATMS 100 1st Editionii. closest to the sun on January 3rd (perihelion)iii. farthest from sun on July 4thb. Year=365.242 daysc. Day= 24 hoursd. southern hemisphere always has opposite seasonXX. Earth’s Axis a. Earth Orbits the sun while tilted on its axisi. tilt is 23.5 degrees and is constant throughout the yearb. axial tilt changes intensity/length of sunlight everywhere on earth throughout the yearc. if no tilt, sun would always be overhead at Equatori. solar radiation intensity same every dayXXI. The Seasonsa. summer occurs when a hemisphere is tilted toward the suni. more intense sunlight over longer hours yields warm tem-peraturesb. winter occurs when a hemisphere is tilted away from the suni. less intense sunlight over shorter hours yields cold temper-aturesc. spring/fallThese 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.i. hemispheres transition from being tilted toward sun to tilted away from the sunXXII. Angle of Suna. sunlight more intense when directed perpendicular to surfaceb. summer:i. more direct sunlight on hemispherec. winter:i. less direct sunlight on hemisphereXXIII. Seasonal Temperaturea. seasonalityi. average temperature change between summer and winterXXIV. Controls of Temperaturea. Latitudei. greater seasonal temperature change near Poles, lesser in Tropicsb. Altitudei. colder temperatures at higher elevationsXXV. Controls of Temperature: Land and Water Distributiona. Land and Water Distribution:i. it take much more energy to heat water than to heat air orlandii. greater seasonal temperature change in interiors of conti-nents, less over oceans and maritime areasXXVI. Controls of Temperature: Winds and Ocean Currentsa. Winds and Ocean Currents:i. greater seasonal temperature changes on east coast of continents, less on west coastXXVII. Daily High Temperaturesa. recall that the troposphere is heated from belowi. sun heats the ground, ground heats the airb. solar radiation (sunlight) typically most intense around noonc. high temperature typically occurs around 3:00-5:00 pmd. see similar 5 week lag in seasonal temperaturese. when incoming solar radiation is greater than outgoing longwaveradiation, the surface warmsi. absorption greater than emissionf. as sun gets lower in sky, solar radiation becomes less intense, sosurface begins to emit more radiation than it absorbs from suni. coolsg. on bright sunny days, warmest temperatures generally right at surfacei. sun heats ground, ground heats airXXVIII. Nocturnal Coolinga. at night, air is cooled from below by cold groundi. ground is blackbody; emits longwave radiation and cools rapidly at nightb. shallow layer of cold air froms just above groundi. nocturnal inversionii. typically few 100 m deepiii. inversions are stable, prevent convectioniv. cold air does not convect upward like hot air doesc. coldest temperatures typically right around sunrisei. ground has been able to cool for a long timed. calm nights tend to be colder than windy nights because the wind mixes the cold air near the ground with warmer airXXIX. The Role of Cloudsa. clouds and precipitation result in relatively cooler temperatures during the day and relatively warmer temperatures at