ABSTRACT This unit cvers the tpics f meterlgy and basic weather predictin, factrs impacting weather, and factrs impacting climate. UNIT 13: WEATHER AND CLIMATE STUDENT NOTES PACKET STUDENT NAME:
Unit 13: Weather and Climate Ntes Packet After Unit 13 yu shuld be able t: Be able t use Selected Prperties f Earth s Atmsphere, Planetary Wind and Misture Belts in the Trpsphere, Temperature, Pressure, Key t Weather Map Symbls, Average Chemical Cmpsitin f Earth s Crust, Hydrsphere, and Trpsphere, and Surface Ocean Currents charts frm the ESRT. Be familiar with the functin f the zne layer Understand the transferences f energy: cnductin, cnvectin, radiatin Understand the Greenhuse Effect, identify greenhuse gases, and understand factrs that impact climate such as cean currents, latitude, and altitude Understand the impact vlcanic eruptins can have n shrt term climate Understand hw air pressure is measured, the key differences between high and lw pressure, and the factrs that impact air pressure Understand hw air pressure plays a rle in weather predictin and wind as well as tls used t measure wind speed and directin Understand and decde air mass symbls and frnts and understand what changes ccur as they pass a weather statin Be able t accurately draw isbars and calculate gradient fr pressure, temperature, etc. Understand the rle prevailing winds play in weather predictin Be able t plan and execute safety precautins in the event f a significant weather event such as a hurricane, lake effect snwstrm, and trnad Be able t fully encde and decde a weather statin with symblic representatins Unit 13 vcabulary yu shuld be able t use and understand: Atmsphere Altitude Trpsphere Stratsphere Messphere Thermsphere Ozne layer Radiatin Cnvectin Cnductin Density Greenhuse effect Infrared radiatin Greenhuse gases Water vapr Carbn dixide Nitrgen Dixide Methane Transparency Lcal Reginal Latitude Inslatin Angle f incidence Barmetric pressure Air pressure Barmeter Atmspheres Millibars Inches f mercury Isbars Gradient High pressure Lw pressure Clckwise Cunterclckwise Crilis effect Cld frnt Warm frnt Statinary frnt Occluded frnt Wind Wind vane Anemmeter Thermmeter Cyclne Anticyclne Prevailing winds Jet stream Air masses Cntinental air mass Maritime air mass Arctic air mass Plar air mass Trpical air mass Atm Mlecule Hurricane Trnad Weather statin mdel Clud cver Visibility Temperature Dewpint Feather Knts Barmetric trend Precipitatin Encde Decde Our atmsphere is incredibly unique and hspitable. Withut ur atmsphere, life wuld nt be pssible n Earth. Frtunately, the gravitatinal pull f the Earth hlds ur atmsphere against the planet. Layers f the Atmsphere Our atmsphere cntains several distinct layers Characteristics f the Atmsphere The layers f the atmsphere are defined by 1 P a g e
Unit 13: Weather and Climate Ntes Packet Unique Layer: The Ozne Layer The zne layer is lcated in the Ozne (O3) prtects rganisms n Earth s surface frm the majrity f the Sun s ultravilet ( ) radiatin T truly understand weather and climate, yu must first understand the methds f transference f heat energy that take place n and arund Earth. Once heat is transferred, it impacts the density f a substance causing it t change its prperties and psitining. This applies t slids, liquids, and gases. Methd #1: Radiatin Radiatin is the transference f energy in thrugh the atmsphere r atms in slids, liquids, and gases Absrptin f these waves by atms can prduce heat Main surces f radiatin: and decay f within the Earth Radiatin and the Electrmagnetic Spectrum Waves f radiatin are defined by the, lnger wavelengths have less energy Lnger wave radiatin, like that f radi waves is harmless, whereas shrter waves such as ultravilet can be harmful with prlnged expsure. The wavelengths and types f radiatin can be fund in the reference tables 2 P a g e
Unit 13: Weather and Climate Ntes Packet Absrbers, Radiatrs, and Reflectrs All bjects (bdies) emit radiatin. Certain characteristics can make sme bdies better radiatrs r reflectrs. (such as infrared) Smth r shiny and light clred surfaces reflect radiatin mre easily and are pr radiatrs/absrbers. Methd #2: Cnvectin Warmer, less dense substances and transfer their heat energy upward Cmmnly fund: (rising warm air, clud frmatin as it cls); (mantle cnvectin) Methd #3: Cnductin Transfer f energy thrugh Example: metamrphism f rcks in cntact with magma; as distance frm magma increases, the grade f metamrphism decreases The Greenhuse Effect: Creating a Hspitable Earth in a phenmenn knwn as the greenhuse effect The sun warms the surface f the Earth as its rays strike the grund and ceans int the atmsphere where it that are present 3 P a g e
Unit 13: Weather and Climate Ntes Packet What are cnsidered greenhuse gases? Greenhuse gases psitively influence climate n Earth (increase temperature) The #1 greenhuse gas is Others include: Cncerns with Climate Change Humans are intrducing at an incredible rate Cncern has arisen because we have fund a crrelatin between atmspheric CO2 cncentratins and a pssible increasing average glbal temperature Other Influences n Wrldwide Climate Vlcanic eruptins cl wrldwide climate as and sulfur dixide are released int the atmsphere, Reginal Climate Factrs Ocean currents in an area and ( based n the type f ) 4 P a g e
Unit 13: Weather and Climate Ntes Packet Elevatin / Altitude Cities lcated abve sea level experience, lw elevatins experience warmer climates Latitude Latitude has the mst significant impact n climate Recall that the Sun is directly verhead latitudes between 23.5 Nrth and 23.5 Suth depending n the time f year Angle f Incming Slar Radiatin (Inslatin) The rays are mre direct during the summer fr the Nrthern Hemisphere While climate is the lng-term descriptin f temperature and humidity trends in an area, weather is the shrt-term descriptin f these factrs in an area. There are many variables t cnsider when generating a frecast. Intrducing Air Pressure Air is a mixture f gases, primarily These gases have mass, and this mass creates n the surface f the Earth This pressure is called 5 P a g e
Unit 13: Weather and Climate Ntes Packet Measuring Air Pressure Air pressure (mre apprpriately barmetric pressure) is measured using a Barmetric Pressure Cnversins Barmetric pressure can be measured using the fllwing units: Unfrtunately, the units are nt unifrm r equal, s a cnversin chart must be used (ESRT) Pressure Trends in the Atmsphere (fewer air mlecules pressing dwn) Barmetric Pressure in Frecasting Air pressure is the best predictr in the general frecasting f weather In basic frecasting, yu can make sme assumptins in yur predictins using nly barmetric pressure Familiarizing Yurself With Isbars Recall that islines islate different measurements Is are islines islating different Drawing isbar rules are the same (if true, g thrugh) Meterlgists term pressure centers depending n the barmetric pressure values assciated with that particular system (abve 1 atm = high pressure, belw 1 atm = lw pressure). 6 P a g e
Unit 13: Weather and Climate Ntes Packet Rtatin f Pressure Centers Winds flw: Cause f Rtatin High Pressure Centers (Anticyclnes) Assciated with High pressure systems making the at times Remember: Lw Pressure Centers (Cyclnes) Changes in temperature, may initially be slightly Lw pressure centers cntain frnts that shw the advancing change in air characteristics. Of these the mst imprtant are cld and warm frnts. Frnts are defined by the characteristics f the air that fllws them. 7 P a g e
Unit 13: Weather and Climate Ntes Packet The Mst Imprtant Frnts: Warm Frnts Frntal bundary fllwed by Clud frmatin and pssible light precipitatin n the leading edge Cld Frnts Leading edge f the cld frnt brings mre frm rapid rising f air abve the appraching Hw are areas f Lw and High Pressure mdeled? maps are created What is an isbar? All values cnnected by the isbar line will be EXACTLY the same Drawing Isbars Islines rules apply If true, g thrugh 8 P a g e
Unit 13: Weather and Climate Ntes Packet What is the cnnectin between wind and air pressure? Winds circulate in the directins n this diagram Wind and Air Pressure Winds als flw pressure system pressure system What affects wind speed? The pressure gradient in a weather system What is a pressure gradient? Recall that the gradient frmula and cncept applies t many different tpics and describes A pressure gradient describes hw quickly Pressure Gradient Widely spaced isbars mean that winds are relatively weak, while Identify lcatins with high winds n this map Instruments Used t Measure Wind Primary Cause f Wind causes sme air t rise when it is heated while ther air cls and sinks (cnvectin) The causes the East t West, cyclnic and anti-cyclnic mtin f wind 9 P a g e
Unit 13: Weather and Climate Ntes Packet Planetary Winds Planetary winds are dependent n the Crilis Effect as well as the angle f inslatin Surface Winds Deflected as a result f the Seasnal Change Whether r nt air is rising and absrbing misture depends n where the mst This figure is shwn at, where the rays are mst intense at the Upper Trpsphere Warmer air will rise int the atmsphere, but then will sink farther t the Nrth r Suth is a reasn fr mst being fund there Prevailing Winds In NYS Jet Stream Mst strm systems traveling t New Yrk arrive frm the Basic weather predictin pint: fr ur ncming weather The Jet Stream is rapidly mving air alft that generates Jet Streams vary with seasn based n heating f the Earth s surface; mving generally Nrth r Suth Wind Influences the Frmatin f Air Masses Air masses are named based n their Their surce regin determines their Air Masses 10 P a g e
Unit 13: Weather and Climate Ntes Packet What factrs impact air pressure? Temperature Humidity Hw d warmer temperatures affect air pressure? Rising temperatures cause air t Expanding air becmes This air creates an area f Recall that winds flw int a Lw in a cunterclckwise fashin, a result f the suctin created by the rising warm air Hw d clder temperatures affect air pressure? Cling trends cause air t cmpress This cmpressin causes the air t becme mre dense and sink This Humidity and Air Pressure The space in the lwer atmsphere can nly hld s many mlecules Humid air cntains different quantities f gas mlecules Masses f Mlecules N2 = 28 g/ml O2 = 32 g/ml H2O = 18 g/ml When water is present in the atmsphere, its mass is lwer This lwer mass results in Humid air is assciated with Lw Pressure Dry air is assciated with High Pressure Label the pressure centers based n humidity n the map 11 P a g e
Unit 13: Weather and Climate Ntes Packet Hurricanes and Trnades Very destructive; hurricanes mre widespread damage (in the Fall) after frming ver the Atlantic Ocean, trnades islated and intense (mstly late Spring and Summer) El Nin and La Nina During years where an El Nin event ccurs, the atmsphere and cean water in the middle f the Pacific Ocean warms La Nina events result in cler water and air temperature in the same regins Cmmunicatin is vitally imprtant in weather predictin and preparatin. Lcal meterlgists are able t cmmunicate cnditins in their area thrugh weather statin mdels. Features Weather statins reprt a variety f infrmatin Clud Cver Hw much f the sky is cvered by cluds? Wind Speed Measured in knts Pints in the directin the wind is cming frm 1 knt = 1.15 mi/hr Temperature 12 P a g e
Unit 13: Weather and Climate Ntes Packet Precipitatin and Visibility Dewpint, temperature at which cndensatin will take place If this is clse t the air temperature it is pssible that precipitatin is ging t take place (high humidity) Barmetric Pressure Yu need t cnvert units befre pltting n the weather statin mdel Reading the mdel: if <500 add a 10 and a decimal befre the last number, if >500 add a 9 and a decimal befre the last number Barmetric Pressure Trend Remve decimal, add rising symbl ( /) r falling (\) Recent Precipitatin 13 P a g e