Presentation on theme: "The Atmosphere Earth’s Weather Heat Transfer"— Presentation transcript:
1The Atmosphere Earth’s Weather Heat Transfer ATMOSPHERE in MOTIONThe AtmosphereEarth’s WeatherHeat Transfer
2Atmosphere – What’s in it? Gases, water and other liquids, microscopic particles of solidsMixture of GASESNitrogen – 78%Oxygen – 21%Argon %Carbon Dioxide – 0.03%AerosolsSolids such as dust, salt, pollen, tiny acid droplets
4Layers of the Atmosphere EXOSPHERETHERMOSPHEREMESOSPHERESTRATOSPHERETROPOSPHERE
5EXOSPHERE IONOSPHERE THERMOSPHERE MESOSPHERE STRATOSPHERE TROPOSPHERE 500 km (310 mi)IONOSPHEREauroraTHERMOSPHEREmeteors80 km (50 mi)60 km (37 mi)MESOSPHERE45 km (28 mi)ozoneSTRATOSPHERE10 km (6 mi)SEA LEVELTROPOSPHERE
6TROPOSPHERE 0-10 km Contains most clouds & weather Contains about 75% of the total mass of the atmosphere
8UPPER LAYERS MESOPSHERE Coldest layer w/ little ozone THERMOSPHERE Warms as it filters out X-rays & gamma rays from sun, which have the shortest wavelengths, are absorbed by oxygen and nitrogen moleculesTransformed into ions.EXOSPHEREContains few atomsNo clear boundary w/ space
9UPPER LAYERSIonosphere Radio waves transmitted from the earth bounce off tiny energy particles called ions, return to a different location on the earth.
11Water filters through soil CondensationPrecipitationTranspirationLeaves give off waterWater filters through soilEvaporationRoots absorb waterGroundwaterWater Cycle
12WATER CYCLE Water on our planet moves in a continuous cycle. water evaporates, heat is absorbed to form water vaporvapors rise, cool and condense into clouds.water droplets become heavy enough to fall -precipitation.water fills lakes, streams and rivers, and eventually flows back into the oceans where evaporation starts the process anew.transpiration by plant leaves: as plants absorb water from the soil, the water moves from the roots through the stems to the leaves, where it can evaporate.
13EARTH’S WEATHER Temperature A measure of how fast air molecules are movingHIGH – molecules moving rapidlyLOW – molecules moving slowlySCALEFreezingPointBoiling PointFahrenheit32212Celsius0100Kelvin273373
15Measurement of Water Vapor Humidity - the amount of water vapor in the airTemperature affects how much moisture is in the airWarmer air can hold MORE moisture – molecules are farther apart creating more space for the water molecules to fit inDew point – The temperature at which water vapor will condenseRelative Humidity – the amount of water vapor present compared to the amount that could be held at a specific temperature
16AIR PRESSURE Weight of air column Warmer air is LESS DENSE – low pressureCooler air is MORE DENSE – high pressure
17AIR PRESSUREDevice used to measure air pressureBarometer
18CLOUDS – How do they form? Air risesCools to its dew point through expansion (Less pressure, molecules spread out, heat is given off)Water vapor molecules "clump together" faster than they are torn apart by their thermal energy.Some of that (invisible) water vapor condenses to form (visible) cloud droplets or ice crystals.
20cloud particles become too heavy to remain suspended in the air PRECIPITATIONRainliquid precipitationHailIce precipitationFreezing rainsuper cooled droplets freezing on impactSleetFrozen raindrops that bounce on impact with the groundSnowan aggregate of ice crystalscloud particles become too heavy to remain suspended in the air
21Air moving from one temperature or pressure area to another WIND - GlobalAir moving from one temperature or pressure area to anotherAffected by Coriolis Effectapparent deflection of air to the right in the Northern hemisphere, to the left in the southern hemispherecaused by Earth’s rotation
27JET STREAMBands of strong winds near the top of the troposphere at the northern and southern boundaries of the prevailing westerlies
28Ocean Currents RELATED Movement of both the air and the oceans is controlled by temperature differencesThe result is a transfer of heat from the equator to the poles. About half the heat transport around the planet is by the oceans, making oceans an extremely important part of the Earth's climate control system. If ocean circulation is changed by global warming, major changes in climate are therefore likely.
29Ocean Currents a Labrador Current b East Greenland C. c North Atlantic Driftd Gulf Streame Canary C.f North Equatorial C.g Caribbean C.h South Equatorial C.i Benguela C.j Brazil C.k Falkland C.l West Wind Driftm West Australian C.n South Equatorial C.o Mozambique C.p Agulhas C.q Monsoon Driftr Kamchatka C./Oya Shios Kuro Shio C.t North Pacific Driftu California C.v North Equatorial C.w Peru/ Humboldt C.x South Equatorial C.y East Australia C.z East Auckland C.Ocean Currents
30Greenhouse EffectThe warming effect of the Earth’s atmosphere is called the greenhouse effect.Gases in the atmosphere that trap solar energy are called greenhouse gasesWater vaporCarbon dioxideMethaneHuman Activities that ADD greenhouse gases:carbon dioxide (produced for example, by the burning of fossil fuels)nitrogen oxides (from car exhausts)Result – could be GOBAL WARMING
31Possible effects of the global warming PositiveFarmers in cooler regions could plant two crops a yearNegativeHigher temperature leads to water evaporating more quickly from soil – leading to “dust bowl” conditionsRise in ocean temperatures could spawn more hurricanesRise in water temperatures would cause the water to expand, raising sea levels around the worldGlaciers and polar ice caps might partially meltCFCs (from aerosols and refrigerators)
32What is Ozone?Ozone is made of three oxygen atoms (O3). The oxygen we find in our atmosphere is made up of two oxygen atoms (O2). Because of its chemical formulation, a single atom of oxygen (O) is unstable. That is, it wants to combine with something else. That is why oxygen is almost always found in pairs, in its O2 (diatomic) form, where it is more stable. Ozone is less stable than O2, because it wants to return to the diatomic state by giving up an oxygen atomOzone is unstable and will readily combine with other atoms.Ozone is found in the stratosphere, where it blocks the sun's ultraviolet (UV) waves and prevents them from reaching the earth's surface.Ozone is also found in the troposphere, where it can damage living tissue and human-produced objects. It is generated both from certain types of pollution and natural sources.Ozone is constantly being formed in the earth's atmosphere by the action of the sun's ultraviolet radiation on oxygen molecules. Ultraviolet light splits the molecules apart by breaking the bonds between the atoms. A highly reactive free oxygen atom then collides with another oxygen molecule to form an ozone molecule. Because ozone is unstable, ultraviolet light quickly breaks it up, and the process begins again.
33Ozone (O3) Cause of thinning ozone layer Chemicals produced by humans CFCs (chlorofluorocarbons)from refrigerators, air conditioners, cleaners for electronic parts, spray cansResultUltraviolet radiation breakdown CFC molecules into atoms, including chlorine (Cl)Chlorine breaks ozone down into oxygen atoms
34Air Pollution Harmful substances in the air Some is naturally occurring – pollen, volcanic ashMuch is caused by human activityMost is a result of burning fossil fuelsCoal, oil, gasoline, diesel fuel≈ ½ comes from motor vehicles (trucks, buses, cars, lawn mowers, scooters≈¼ comes from electric power plants and factories burning coal and oil
35SMOG Photochemical Smog Caused by the action of sunlight on chemicals Nitrogen oxides – Nitrogen Oxide (NO) produced from burning fossil fuels reacts with oxygen in the atmosphere to make Nitrogen Dioxide (NO2)Hydrocarbons – organics given off by some plants, from fuels evaporating and incomplete burning of fuelThese along with others react with each other in the presence of sunlight to form a mix of ozone and other chemicalsSMOG
37ACID RAIN – What is it?Sulfur dioxide (SO2) and nitrogen oxides (NOX) released into the air from burning fossil fuels.Combined with water and other chemicals, sulfur and nitrogen oxides become sulfuric and nitric acid.These acids may travel long distances before falling to the earth as rain, snow, sleet, hail, fog, dew or dust.
38ACID RAIN – How do you know? Acid rain is measured using the pH scale.The pH scale ranges from 0 (very acidic) to 14 (most alkaline). Seven is neutral.Rain is by nature slightly acidic, with a pH of 5.6. Any precipitation below that is considered "acid rain".Because the scale is logarithmic, a pH of 4.6 is ten times more acidic than normal rainwater and a pH of 3.6 is a hundred times more acidic.The average pH of rain in Vermont is between 4.2 and 4.4 with extremes ranging from 2.4 to 7.4.
41ACID RAIN – Solutions?SCRUBBERS - filters in smokestacks of factories and power plants to remove pollutants Very expensive to install.USE ALTERNATIVE ENERGY PRODUCTION METHODS – Wind or solar power not harmful to the environment. However, the cost of replacing all of the fossil fuel power stations with either wind farms or solar power is prohibitive and almost impossible. It would take 600 wind turbines to produce the same electricity as one coal-fired power station.USE LESS ENERGY – insulate houses better, lower ceilings, use the car less, walk more, bicycle, public transportationCATALYTIC CONVERTERS - catalytic converters on car exhausts remove around 90% of the pollutants released during the combustion process.