Meteorology Review Sheet Test 1 I An Introduction to some Meteorological Products a Meteorological Satellites 1 Visible Satellite Images useless at night like taking a picture with a camera from space 2 Infrared Satellite Image Seeing temperature of cloud tops or of Earth s surface Can be used day or night White Cold Black warmer 3 Water Vapor Satellite Images amount of water vapor present in atmosphere dark shades dry areas light shades moist area b Doppler Radar antennae send out radio waves rain and other objects reflect radio waves objects moving away decrease wave frequency can tell where and how much intensity is falling can tell how fast and in what direction the air is moving Radar Images show presence of hydrometers snow rain sleet hail can cover entire country show intensity location and TYPE of precip that is falling over a given region nearly entire country is covered by Doppler Radar Satallites late 1960s Radar 50 years fairly c Surface Weather Maps low atm pressure L poor weather conditions clouds precip winds spiral counter clockwise around areas of low pressure high atm pressure H fair weather conditions sunny partly cloudy winds spiral clockwise around areas of high pressure Cold front Warm Front cold pushed warm out warm replaces cold doesn t push cold out teeth and circles point in direction the front is moving Surface observations ASOS sites Automated Surface Observing Systems d The Station Model tell us the weather at a site in small space by looking at a map with station models plotted on it can get a feeling for weather across that area Circle gives location of the station amount of coverage inside the circle gives cloud coverage high dew point means a lot of water vapor pressure in millibars Wind speed long 10 knots short 5 knots wind direction points in direction from where the wind is coming e Computer Model Forecasts first we observe the current state of the atmosphere assume we can describe the atmosphere with math equations use observations we take with equations to predict what the atmosphere will look like in the future billions calculations must be completed to run the model to some specified time model forecasts can be made from hours to 14 days in advance II Introduction to the Atmosphere the sun is the energy source for the atmosphere constantly being fused into He Surface is 6000 C interior is millions C a Atmospheric Composition Mixture of gases N O Ar make up 99 9 of gases in the air 78 N 21 O 9 Ar CO2 and other gases water vapor 0 4 CO2 036 360ppm Ozone 000004 04ppm Water vapor clouds precipitation absorbs infrared radiation CO2 absorbs infrared radiation greenhouse gas Ozone absorbs UV radiation from the sun b Temperature and pressure structure of the atmosphere temp is the amount of heat energy present in a substance heat energy is the measure of average kinetic energy of molecules KE mv2 faster molecules mean higher temps Tr St M Th weather action layer temperature decreases with height oposphere lowest layer surface to 10km wv atosphere 10 47 km Ozone max at 25km esosphere 47 80 km ermosphere 80 km or 50 miles Vertical variation of temp is important a normal lapse rate is where temp with height if then we say an inversion is taking place Atmospheric Pressure and Density atm pressure force exerted by the atmosphere on some specific area at surface 1m3 of atm has mass of 1kg or 2 2 lbs at sea level pressure exerted by area is 15lbs in2 about 7 textbooks atm pressure is dependent on total mass of atm in column above that point atmosphere is compressible average atmospheric pressure is 1013 2 mb D of atm and atm pressure decrease rapidly with height D m v surface pressure at a location is constantly changing must be someway molecules are being taken either into or out of air column pressure differences between locations cause the winds to blow measure pressure with a barometer Toricelli barometer 1643 mercury doesn t expand or contract like other metals do Pressure Units in of mercury millibars pascals now we use aneroid barometer Range of atm Pressure 960 1060 mb on a station model if it says 109 10 9 then must decide whether to put a 9 or 10 in front of it 910 9 is way too low so 1010 9 is the atm pressure white lines on map are lines of constant atm pressure known as isobars the closer together the isobars the greater the wind speed Temperature 32 F 212 F 0 C 100 C Freezing Boiling Celsius is about 2 times larger than Farenheight 2 F 1 C F C x 1 8 32 C F 32 1 8 Earths observed temperature range is 265 F 273K 373K III Energy in the Earth Atmosphere System a Earth Sun relationships Reason for the Seasons Orbit around the sun in 365 25 days closest to sun on January 3rd Perihelion Furthest from the sun on July 4th Aphelion average distance between earth and sun is 93 mil miles 150 mil km our seasons are related to amt of solar energy received at surface 1 angle by which sunlight strikes surface less energy at horizon 2 amt of time sun is above the horizon 3 amt of atm that energy from sun must pass through Tilt of the Earth is 23 5 Summer Solstice June 21 and 22 sun is directly overhead at 23 5 N at noon Tropic of Cancer Northern Hemisphere is tilted towards the sun Days are longer in the Northern Hemisphere Winter Solstice December 21 and 22 sun directly ahead at 23 5 S Tropic of Capricorn Southern Hemisphere is tilted towards the sun Days are short in the northern hemisphere Vernal Autumnal Equinox March 21 22 or September 21 22 sun directly overhead at noon at equator sun at horizon all day poles at every point on earth there are 12 hours of daylight High latitude areas have a larger annual temperature range than near equator b Energy Work Heat energy the ability to do work work done on an object when it is pushed pulled kinetic energy dependent on the speed of movement of the molecules heat transfer the transfer of energy between two substance Heat always flows from the hotter to a cooler object transfer of heat can be accomplished bug our processes conduction convection radiation latent heating heat capacity ratio of the amount of heat energy absorbed by the substance to the temperature change that occurs in the substance Change in heat change in temp large heat capacity change in temp very slow water has a very large heat capacity earths surface has a small heat capacity sand heats up and cools very fast specific heat amount of heat transfer needed to raise temp of 1g 1 C Water exists in three phases Absorbs heat Releases heat S L