Presentation on theme: "Higher Atmosphere Earth’s Heat Budget Global Insolation"— Presentation transcript:
1 Higher Atmosphere Earth’s Heat Budget Global Insolation Global Transfer Of EnergyGlobal TemperaturesInter Tropical Convergence ZoneClimate Graph
2 100% Short Wave Solar Energy (Insolation) Limit Of Atmosphere100% Short Wave Solar Energy (Insolation)26% Reflected (Albedo) By Clouds18% Absorbed By Atmosphere6% Reflected (Albedo) By Earths Surface (Long Wave)50% Absorbed By Earths Surface
3 100% Short Wave Solar Energy (Insolation) Limit Of Atmosphere 26% Reflected (Albedo) By Clouds18% Absorbed By Atmosphere6% Reflected (Albedo) By Earths Surface (Long Wave)50% Absorbed By Earths Surface
4 SOLAR INSOLATION IN EARTHS HEAT BUDGET 100%solar insolationreflected by atmosphere26%TOTAL ALBEDO == 32%18%absorbed by atmosphere56%reaches surfaceTOTAL ABSORPTION == 68%reflected by surface6%absorbed by surface50%
5 The Heat BudgetOnly 50% of the incoming solar radiation (insolation) which reaches the atmosphere from the sun, actually penetrates to the surface of the earth.Energy which is lost is done so in 2 ways through reflection and through absorption.
6 Earth’s Heat Budget (Task 2) This is incoming solar energy (heat).Earth’s Heat BudgetInsolationAlbedoLong Wave RadiationThis is energy or heat emitted from the earth, only 6% escapes the earth the rest being absorbed into the atmosphere.This is the total amount of energy reflected from the earth.This is the balance between incomingand outcoming energy.
7 The Earth’s Heat Budget To help you, use the following structure.Say where the earths energy come from and name it.Briefly explain what the earth’s heat budget is.Describe what happens to the insolation giving values;Atmospheric absorption (clouds)Atmospheric reflection (albedo + clouds)Surface absorption (land)Surface reflection (albedo + ice/water)
8 Earth’s Heat Budget (Task 3) The earths energy comes from solar radiation, this incoming heat energy is balanced by the amount of heat escaping back into space. This balance is called the earths heat budget.Incoming solar heat (insolation) from the sun is absorbed and reflected meaning not all the heat reaches the earths surface. 26% of the energy is reflected back into space by the earths atmosphere and 18% of the heat is absorbed by the atmosphere due to dust particles retaining the heat.This leaves 56% which travels to the earths surface. Not all of this is absorbed 6% is reflected from the earths surface by polar ice caps & water, and this makes up part of the earths Albedo. This means only 50% reaches the earths surface and is balanced out by the long wave radiation escaping back into the atmosphere.
9 Variations in Global Temperatures To understand the reasons as to why the poles are in deficit and the equatorial regions have an energy surplus
10 Global InsolationThe Earth's atmosphere is put into motion because of the differential heating of the Earth’s surface by solar insolation.This means that the winds and clouds above us move around because there are some areas of the earth which are hotter than others.We therefore need to know why these difference occur, so we can then study the different movements of the weather in the atmosphere. This then lets us make accurate weather forecasts.
11 Variations in Insolation The amount of insolation at the Earth’s surface varies according to latitude – most heat is received at the Tropics and least heat is received at the Poles.As a result, there is a net gain of solar energy in the tropical latitudes and a net loss towards the poles.
12 Reasons for Variations in Insolation Surface area to be covered is greater at Poles than Tropics so more insolation lost at Poles.More atmosphere to pass through at Poles than Tropics so more insolation lost at Poles.Position of sun – the sun is high in sky all year round at Topics whereas at Poles there is no insolation for 6 months of the year.Albedo. Snow and ice covered Poles reflect insolation. Forested Tropics absorb it.
13 Differing Depths Of Atmosphere Global Insolation Task 4 (1)Differing Depths Of AtmosphereDifferentCurvatureDiffering AlbedosHigh AlbedoLowAlbedoInsolationEnergy FromThe Sun
14 Global Insolation Task 4 (1) Different CurvatureHigh AlbedoInsolationLowAlbedoDiffering Depths Of Atmosphere
15 Task 5 Latitude & Distribution Of Solar Energy Distance: Insolation from the sun travels different distances, and hence amounts of air, because of the curvature of the earth. At the equator there is a shorter distance to travel, but at the poles there is a greater distance to reach the land. This means that the insolation will be weakened more approaching the poles than at the equator and so make it cooler at the poles.Curvature: The curvature of the earth also has an effect on the distribution of solar energy. The sun’s rays are more concentrated at the equator so it is hotter or has more solar energy. At the poles the same rays are spread over a greater distance so there heat is spread making it cooler. The poles therefore have less solar energy than the equatorial regions.Albedo: The high quantities of ice at the poles mean there is a high albedo (reflection), so that insolation is reflected and the poles receive less solar heat/radiation. The equatorial regions have high concentrations of rainforest, the dark green colour absorbing insolation and so receive more heat.
16 Variations In Global Insolation DescribeWith the aid of an annotated diagram describe and explain the energy balance shown on the diagram below.Range of latitude35° to 0° (N or S of) Equ.State if in deficit or surplusGive values in Joules 170 to 270Range of latitude35° to 90°N or S of Equ.State if in deficit or surplusGive values in Joules 50 to 170
17 Variations In Global Insolation Explain In DetailWhy deficit in high latitudes (polar areas) and why surplus in low latitudes (equatorial areas)Insolation - distance travelled through atmosphere greater at poles so heat lostConcentration of insolation higher at equator due to curvature of earthAlbedo high at poles and low at equator
18 Global Transfer Of Energy This is the movement of energy from the equator to the poles. Global Insolation differences should mean that the lower latitudes (equator) get hotter and hotter, whilst the higher latitudes (poles) get colder and colder.In reality this doesn’t quite happen as energy is transferred from surplus areas (equator) to deficit areas (poles) by two methods.Atmospheric Circulation & Ocean Currents
19 Atmospheric Circulation (Task 7) The air warms again and so rises giving rainAtmospheric Circulation (Task 7)The cool air then starts to fall back to the earthFinally the cool air sinks at the poles having distributed heat from the equator to the polesHot air at the equator risesThis cools as it rises giving cloud and then rain
20 Colour in the cells A, B & C. 0°30N°60N°90N°ABCA = Hadley CellB = Ferrel CellColour in the cells A, B & C.C = Polar Cell
22 Atmospheric Circulation Cells The three weather cells.The Hadley Cell ~ this circulates air between the equator 0° and the tropics of, Capricorn in the south (30°S) & Cancer in the north (30°N).The Polar Cell ~ this circulates air between the North Pole & the Arctic circle (90°N & 60°N)The Ferrel Cell ~ this isn’t actually a cell but circulates air through friction between the tropic of Cancer & Arctic Circle in the North (30°N & 60°N) and the Tropic of Capricorn & Antarctic Circle in the south (30°S & 60°N)
23 Atmospheric Circulation Hadley Cell Equatorial Low PressureSub Tropical High PressureSub Tropical High Pressure
24 Atmospheric Circulation Polar Cell Cool air falls at the poles. Polar High PressureAs the air rises it starts to cool.90°N °NThe warm air rises at 60°N. Temperate Low Pressure.The air spreads south, warmed by the sea and land.
25 Atmospheric Circulation Ferrel Cell PolarCellHadleyCellHadleyCellFerrelCell90N° N° N° ° S°Rising warm air from Polar Cell pulls up air with it.Descending cool air from Hadley Cell drags down more air with itAir dragged by both Cells causes air to circulate, Ferrel Cell, and distribute heat from the equator to the poles.
26 Atmospheric Circulation Winds The next slide shows how winds move across the surface of the earth.A Key Principle is that these winds move from areas of high pressure to low pressure.Complete the diagram showing surface winds in your workbook.
28 0°30N°60N°90N°60S°30S°90S°Air falling at the Polar High Pressure (90°N) move towards the Temperate Low Pressure (60°N) called Polar Easterlies.Falling air at the Sub Tropical High Pressure (30°N) moves towards the Temperate Low Pressure (60°S) called Westerlies.Falling air at the Sub Tropical High Pressure (30°N) also moves towards the Equatorial Low Pressure (0°) called the North East Trade Winds.The last winds we really need to know are called the South East Trade winds which result from falling air (high pressure) at 30°S.Where air rises at the Equatorial Low Pressure there are light wind called the Doldrums.
29 Ocean Currents - Global Transfer Of Energy Ocean currents like Cells and wind redistribute energy. Heat is taken from the tropics and moved towards the pole & vice versa.For the exam you will have to describe the movement of these currents and be able to explain why they move in the way that they do.
30 Description of Ocean Currents Help redistribute energy from areas of surplus to deficit.Account for 20% of energy redistribution.Warm currents flow from Equator to Poles.Cold currents flow from Poles to Equator.Warm currents – Gulf Stream, North Atlantic Drift.Cold currents – Canary, LabradorMove in large circular loops called gyres.Clockwise in the Northern Hemisphere.Anticlockwise in the Southern Hemisphere.
31 Factors influencing the flow of Ocean Currents Winds – currents follow prevailing winds.Land Masses – block and deflect currents and send them off in other directions.Corioilis Force - deflects currents to the right in the northern hemisphere and the left in the southern hemisphere.Salinity(salt) differences in water – flow from low to high salinity – equator – sub-tropics.Uneven heating of water – cold polar water sinks, flows towards equator and displaces upwards the warmer water setting up gyres.
32 Colour this line red, it is the warm Gulf Stream Colour this line in blue, it is the cold Labrador current.Colour this line blue, it is the cold Canaries CurrentColour this line red it is the warm Equatorial Current
33 Ocean Currents Description The currents of the oceans circulate in large loops called gyres.These currents form in warm equatorial areas and cold polar areas.In the North the currents flow in a clockwise direction.In the South the currents flow in an anticlockwise direction.
34 Ocean Currents Description In the North Atlantic Gyre a warm current from the equator heads towards the Caribbean, the North Equatorial Current. It then moves in a North Easterly direction towards Europe, as the Gulf Stream Current.A cold current from Northern Canada, called the Labrador current joins the Gulf Stream cooling it down. The current starts to flow south down the African coast to the equator, the Canaries Current, but by now is much cooler. The cycle then starts to repeat itself.
35 Ocean Currents Description The distribution of heat can actually be seen in a figure of 8 pattern as the two gyres in the Atlantic meet at the equator. Remember in these questions you must mention that the warm water spreads heat pole wards and the cool water helps cool the equatorial regions.The current then turns Easterly towards South Africa and flows up its Western coast, the Benguela Current. The current starts to warm up again as it moves up the African coast where it rejoins the warm South Equatorial Current.Some of the warm current from the equator, South Equatorial Current, starts to flow South West to the Brazilian coast, Brazilian Current, cooling as it travels South.
36 Ocean Currents Explanation When explaining how these currents circulate there are 4 key points to make as well as one explaining temperature chnages;WindCoriolis effectPosition Of ContinentsConvection CurrentsYou also need to know why the currents warm or coolFor Task 14 you will split into groups to find out about these key points, reporting back to each other what you find.
37 Ocean Currents Explanation Prevailing WindsThe Trade winds and the Westerlies drive the ocean currents in a clockwise direction a result of falling & rotating air at the sub tropics (30ºN). The equatorial current is picked up by the North East trade winds & sent to the caribbean, the rotation then continues so that the Westerlies send the current to the North East.North EastTrade WindsWesterlies
38 Ocean Currents Explanation Coriolis EffectThis is the West to East rotation of the earth that drives the ocean currents the northern hemisphere in a clockwise direction
39 The continents deflect currents into a clockwise movement Ocean Currents ExplanationNorth AmericaEuropeThe continents deflect currents into a clockwise movementAfrica
40 Ocean Currents Explanation More insolation received at the equator than the poles results in convection currents. Warm currents rise at the equator and then drop back down into the sea at higher latitudes, helping to mix warm and cold currents.
41 Ocean Currents Explanation Explaining distribution of cold and warm temperature by currents.You also have to state the obvious!As warm currents move northwards from the equator, they distribute heat to the cooler high latitudes nearer the poles.At the same time, movement of cold currents from the poles to lower latitudes helps to distribute cool temperatures to the warm equatorial areas.
42 Changes In Global Temperatures Diagram Showing Global Temperature Variations-0.8This TrendFluctuates Upwards-0.6+0.4Global Mean TemperaturesHave Risen+0.2Average Global Temperature0°C-0.2-0.4-0.61975200018501875190019251950
43 Changes In Global Temperatures Diagram Showing Global Temperature VariationsLowest value -0.42°CHighest Value 0.4°CTemperature Range 0.82 °C+0.8+0.6+0.4+0.2Average Global Temperature0°C-0.2-0.4-0.61975200018501875190019251950
44 Changes In Global Temperatures Diagram Showing Global Temperature Variations-0.8-0.6+0.4Rapidly Increasing Temperature Above Average+0.2Average Global Temperature0°C-0.2 to -0.1°C below Average Temperature-0.2-0.4 to – 0.3°C Below Average Temperature-0.4-0.61975200018501875190019251950
46 Changes In Global Temperatures The overall trend is that the Global mean temperature has fallen/stabilised/risen between 1850 & 2000, in a steady/fluctuating manner against the 1951–1990 average/long term average. The lowest value was -0.42/-0.38 °C and the highest +0.4 °C giving a range of -0.2/+0.2/0.78/0.82 °C around the mean for There was a period with below average temperatures of around -0.4°C to °C between 1850 & 1920/1850 & 1950/1940 & There was a period of gentle increase between -0.2°C & -0.1°C below the 1950 average from 1920 & 1940/1920 & A period of slow/moderate/rapid increase above the 1950 mean took place between 1940 & 2000/1975 & 2000.
47 Changes In Global Temperatures Physical FactorsDust from volcanoes reflects away insolationSunspot activity sends more insolation to the earth
48 Changes In Global Temperatures Physical FactorsIf the earth’s orbit changes we can be further from the sun and start to cool.
49 Changes In Global Temperatures Physical FactorsIf the earth tilts away from the sun the Northern Hemisphere will cool
50 Changes In Global Temperatures Human FactorsCO2 absorbs heat and reradiates heating up the earth.Deforestation adds CO2 when trees burnt and less CO2 converted into water by trees.Methane, Nitrous Oxides & CFC emissions do the same as CO2.
51 Inter Tropical Convergence Zone (ITCZ) This is simply the area between the two Tropics (Cancer & Capricorn) where two different air masses meet. As it is a low pressure area/belt there is rain. This is a result of the high levels of insolation at the equator causing the movement of warm air upwards.First try and work out a few definitions for Task 16, use your knowledge of the English language & your teacher to help.
52 Inter Tropical Convergence Zone (ITCZ) between the tropicsof Cancer & Capricorn.Inter TropicalConvergenceZonewhere two or morethings meets in this case air masses?ITCZan areaTask 16
53 ITCZThe migration of the inter-tropical convergence zone (ITCZ) in Africa affects seasonal rainfall patterns across the continent.It is an area of low pressure that forms where the Trade Winds meet near the earth's equator.As these winds converge, moist air is forced upward. As it rises, the air cools, resulting in a band of heavy rain around the globe.This band moves seasonally, due to the changing position of the overhead sun.
55 Position of the ITCZ: January Tropicof CancerEquatorTropicof Capricorn
56 Task 17 ITCZ Air Masses Air masses = ? Tropical climate = ? & why Maritime climate = ? & whyTropical Continental (cT) DryContinental climate = ? & whyWhen describing air masses you must say;Where they developWhere they move toHow stable they areTheir temperature & moisture characteristicsWhat the weather will be likeTropical Maritime (mT) Wet
57 Task 18 ITCZ JanuaryRain as sun & ITCZ located over Tropic of CapricornTropical Continental DryDry area north of ITCZ as Continental air is dry and stable, from Sahara DesertITCZTropical Maritime Wet
58 Task 18 ITCZ March Rain around equator as ITCZ located by it Tropical Continental DryWet area south of ITCZ as Maritime air is wet and unstableDry area north of ITCZ as Continental air is dry and stableTropical Maritime Wet
59 Task 18 ITCZ July Rain as sun and ITCZ located over Tropic of Cancer Tropical Continental DryITCZWet area just south of ITCZ as Maritime air is wet and unstableSome convectional rainfall between 5º N & S of the equator.Tropical Maritime Wet
60 Task 18 ITCZ September Rain around equator as ITCZ located by it Tropical Continental DryWet area south of ITCZ as Maritime air is wet and unstableDry area north of ITCZ as Continental air is dry and stableTropical Maritime Wet
61 JanuaryEquatorTropic of CapricornTropic of CancerITZC
62 MarchTropic of CancerICTZEquatorTropic of Capricorn
63 JulyTropic of CancerICTZEquatorTropic of Capricorn
64 SeptemberEquatorTropic of CapricornTropic of CancerICTZ
65 JanuaryTropic of CancerITZCEquatorTropic of Capricorn
66 MarchTropic of CancerICTZEquatorTropic of Capricorn
67 JulyTropic of CancerICTZEquatorTropic of Capricorn
68 SeptemberTropic of CancerICTZEquatorTropic of Capricorn
69 JanuaryTropic of CancerITZCEquatorTropic of Capricorn