GEO 101, Feb 4, 2014 Finish isolines Atmosphere intro Variation in incoming solar radiation. Freezing rain is supercooled liquid water

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1 GEO 101, Feb 4, 14 Finish isolines Atmosphere intro Variation in incoming solar radiation Freezing rain is supercooled liquid water Graupel is white because it has air trapped inside leet is more colorless leet: frozen raindrops that bounce on impact with the ground Quantitative means the THEME has VALUE Daily Average olar Radiation Isolines: lines that connect points of equal value and enclose areas of equal value. Isoline interval: difference between value of successive isolines

2 Isolines that show elevation are contour lines Isolines that show elevation are contour lines Isolines that show elevation are contour lines Match the map to the shape Isolines for GEO 101 Precipitation : isohyets Temperature : isotherms Atmospheric pressure : isobars A D B E C F Isoline rules: 1. All locations on a given isoline have the same value 2. Closed isolines represent a high or a low set of values Isoline rules: 3. Widely spaced isolines represent gradual changes in values 4. Closely spaced isolines represent abrupt changes in values Everything inside is less than

3 Isoline rules: 5. All isolines eventually close either on or off the map 6. Isolines never cross one another Draw in 150, 100, & 50 isohyets 7. Isolines never split or have branches Atmosphere: blanket of air surrounding earth 1. Insulator 2. hield (meteors, ultraviolet radiation) 3. Enables travel of sound waves, aircraft Air molecules 3 mi Without our atmosphere: cold, quiet, cratered place Dynamic: currents and circulation cells Atmosphere important in equalizing temperature and pressure by transfer of heat, energy, and moisture around world Altitude (km) Air pressure Air density mi 90% in first 10 mi 10 mi Little info. tratosphere Layers of the atmosphere based on temperature It gets colder as you go up in the troposphere because you get farther from the earth, the main heat source. Tropopause Meteorology...the study of weather condition of atmosphere at a given time for a given area temperature, pressure, wind, moisture Climatology...the study of long term average weather usually over past 30 years Troposphere We live in the troposphere 3

4 Driving force behind weather and climate How bright the sun shines Total insolation is a function of intensity x duration Primarily related to latitude Factors affecting intensity 1. Angle of the sun s rays 1. Angle of the sun s rays affects intensity of insolation Latitudinal comparison Angle of incidence urface area covered How bright the sun shines Factors affecting intensity 1. Angle of the sun s rays 2. Atmospheric transparency (clouds, etc.) (Latitude and season affect angle of sun s rays) 2. Atmospheric transparency affects intensity of insolation Clouds Air pollution moke Volcanic ash: Chile, 1993 Dust storm approaching tratford, Texas. Image ID: theb1365, Historic C&G Collection, April 18, 1935, Credit: OAA George E. Marsh Album 4

5 100% at top of atmosphere 5% scattered or reflected 15% absorbed by molecules and dust 80% can reach ground on clear day 5-% absorbed by clouds 30-60% reflected by clouds 0-45% reaches ground on cloudy day How bright the sun shines Factors affecting intensity 1. Angle of the sun s rays 2. Atmospheric transparency 3. Altitude The higher up you are, the fewer air molecules are between you and the sun Air molecules 3 mi 3. Altitude affects intensity of insolation Mt. Everest, 5.5 mi high Altitude (km) Air density mi Air pressure 90% in first 10 mi 10 mi March Equinox How long the sun shines during the day Depends on latitude and season June December ept. Equinox 5

6 .Pole.Mid-Lat Equator.Mid-lat. Pole Approximate Duration of Insolation pring Equinox June hrs. ~ hrs ~8 hrs. 0 hrs. Fall Equinox December 0 hrs. ~8 hrs. ~ hrs hrs. Arctic midnight sun -latitudes, low angle sun Mid-latitudes: sun never directly overhead Range in elevation of noon sun Equator: 90 to 66.5 Tropics: sun is directly overhead once or twice a year Low latitudes Mid-latitudes: sun never directly overhead Equinoxes 66.5 Equinoxes latitudes, low angle sun Range in elevation of noon sun Tropic of Cancer: 90 to 43 Range in elevation of noon sun Mobile: 83 to 36 Mobile = 30.5º Tropic of Cancer = º Difference = 7 7 June

7 Range in elevation of noon sun Anchorage, AK: 52.5 to 5.5 Anchorage = 61º Tropic of Cancer = º Difference = 37.5 Range in elevation of noon sun orth Pole: to 0 orth Pole = 90º Tropic of Cancer = º Difference = Can you look north? Equinoxes What is the top of the easonal variation in insolation at top of atmosphere atmosphere? Equator Poles Duration Angle Total Duration Angle Total pring Equinox Low um. - - hrs Low Fall Equinox Low Winter hrs. Below horizon Zero TROPIC: insolation high year round due to high sun angle and ~ constant duration Mid-latitudes: insolation highest at summer solstice due to higher sun angle and longer day, lowest at winter solstice due to low angle and short day Total annual insolation decreases as latitude increases easonality (difference between winter and summer) increases as latitude increases Poles: insolation highest at summer solstice due to hour duration low angle sun, none at winter solstice 7

8 Global average annual energy balance Insolation on the June Comparison between top of atmosphere and Earth surface urplus Duration factor Top of atmosphere Tropics Deficit Mid- latitudes Equator. Pole an Francisco t. Louis Washington DC At top of the atmosphere Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec Megajoules/m 2 /day 90 sun elevation Chart monthly insolation at the Equator Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec Chart of monthly insolation at the Equator Chart monthly insolation at the orth Pole Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec 8

9 50 45 Chart of monthly insolation at the orth Pole (dark bars =.P., light are Equator for reference) Chart monthly insolation at the outh Pole Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec Jan Feb Mar Apr May Jun Jul Aug ep Oct ov Dec Example only, do not use your sheet for this demo. problem. 90 Class assignment: if your last name begins with A-B, do 80 and 10 C-D, do 70 and E-H, do 60 and 30 I-L, do 50 and M, do and 50 -Q, do 30 and 60 R-T, do and 70 U-Z, do 10 and 80 9