Insolation and Temperature

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Insolation and Temperature
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Objective

• To study about the basic processes in heating and
  cooling and how they affect our atmosphere
• Relate that to global warming and green house
  effect to people and environment

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Outline

• Review of Chapter 3
• Impact of temperature on the landscape
• Solar energy
• Basic Processes in Heating and Cooling of
  Atmosphere
• Heating of the Atmosphere
• Spatial and Seasonal Variations in Heating
• Heat and Temperature
• Heat Transfer Mechanism
• Vertical Temperature Patterns
• Global Temperature Patterns
• Global Warming and Green House Effect
• Measuring Temperature

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Review

• Permanent Gases N2 Oxygen and Argon
• Variable
• Water vapor
• Methane
• CO2
• N2o
• O3
• Particulates

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Pressure
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Vertical Profile
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Weather and Climate

• Elements of weather and climate
• Temp
• Pressure
• Wind and
• Moisture
• Complex interaction
• Frequently change in space and time

• Control of Weather and Climate
• Latitude
• Distribution of land and water
• General circulationTropics east, Mid lat west
• Elevation Temp, pressure moisture decreases with
  altitude
• Topographic barriers rain shadow
• Storms interaction of climatic control factors
  can cause special cases

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Ozone reactions

• Eq 2 can absorb ultra-violet radiation of
  wavelength 10.1-14.0 x 1014Hz and undergo photo
  dissociation
• O3 hv O2 O (5)
• When CFC's are destroyed they form Cl radicals.
  These chlorine radicals react with ozone
• ClO3 O2ClO (6)
• The ClO formed is another reactive free radical,
  which can react with oxygen atoms.
• ClOO ClO2 (7)
• OO2 O3 (2

• Ozone absorbs UV radiation in its formation and
  breakdown O2absorbs UV light to form 2 oxygen
  radicals
• O2 hv O O (1)
• The oxygen radicals can then react in one of
  three ways
• OO2 O3 (2)
• OO O2 (3)
• OO3 2O2 (4)

Reaction 4 and 6 competing Conc. of Cl less than
O but reaction rate 1500 times faster. Cl acts as
catalyst
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Impact of Temperature on Landscape

• Animals and plants evolve in response to
  temperature/climates
• Soil development is temp dependent
• Human built-landscapes in response to temperature

What are waves Disturbance propagated through
space that transforms energy
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Temperature

• Energy Capacity to do work
• Heat A form of energy, speed of molecular
  vibration
• Temperature Degree of hotness
• Sensible heat relative heat

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Measuring Temperature
       oF (9/5)oC32 oK 273.15 oC   
oC (5/9)(oF-32)  

• Fahrenheit
• Celsius
• Kelvin
• Thermographs
• Daily mean
• Range
• Monthly mean
• Annual mean
• Annual range

At absolute zero molecules do not move Zero
energy, coldest.
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Measuring TemperatureFahrenheit Scale
Celsius ScaleKelvin Scale
Figure 4-B
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Solar energy

• Energy travels at the speed of light (8 min to
  reach earth 93,000,000 mi) Solar constant const
  temp (2 Langley's/min) at the top of the
  atmosphere
• 1 Langley 1 cal/sq.cm
• Speed of light is
• 299,792,458 m/s (meters per second)
• Solar energy consists of electromagnetic waves
• 0.01 -0.4 micrometer Ultra-violet waves
• 0.4-0.7 micron visible
• 0.7 1,000 micron Infrared

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Solar EnergyThe Electromagnetic Spectrum
Figure 4-4
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Basic Processes in Heating and Cooling

• Heat energy moves in three ways Radiation,
  conduction and convection
• Radiation Process of emission of electromagnetic
  waves
• Absorption ability to assimilate heat
• Reflection Ability to repel without altering
  object or wave
• Scattering Changing of direction of waves but no
  change in wavelength
• Transmission Passing completely through medium
  LW gt 4 micrometer SWlt4 micrometer
• Green House effect

• Conduction Movement of energy from one molecule
  to other
• Convection/Advection Transfer of heat by moving
  substance
• Adiabatic Cooling (rising air lighter, less
  pressure) and Adiabatic Warming (heavier, more
  pressure, descending air)
• Latent Heat energy stored or released
• Evaporation latent heat stored, a cooling
  process
• Condensation Latent heat released, warming
  process

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Radiation
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Absorption and Reflection
Figure 4-8
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Scattering
Figure 4-9
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Transmission
Figure 4-11
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The Heating of Atmosphere

• Net insolation received and net radiation
  returned
• 8 units net gain every year
• Evaporation depends on latent heat of evaporation
  as there is more water. More latent heat is
  stored
• Heated from below
• Constant convective activity and vertical mixing
  Albedo ability to reflect radiation

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TransmissionThe Greenhouse Effect
Figure 4-12
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Spatial and Seasonal Variations

• Land and Water Contrasts
• Heating
• Land heats and cools faster than water
• Specific heat Amount of heat energy required to
  raise the temperature through 1 degree C. Land
  has 5 times sp heat than water
• Transmission, mobility, moisture and evaporation
• Cooling Cools slowly , entire body of water must
  be cooled
• Role of oceans Thermostatically controlled heat
  source that moderates temperature
• N Hemisphere has more extreme than S hemisphere
  because of oceans

• No even distribution
• Depends on how it receives energy
• Latitudinal difference
• Angle of incidence
• Day length
• Atmospheric obstruction Particulates, cloud and
  gas molecules)
• Latitudinal radiation balance ( deficit in poles,
  low lat 28N and 33 S) get surplus radiation

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Mechanisms of Heat Transfer

• Atmospheric Circulation Advective 75-80
  otherwise tropics would be inhabitable
• Oceanic Circulation Ocean currents reflect
  average wind conditions over several years
• Atmospheric and oceanic currents are driven by
  latitudinal imbalance of heat
• Basic pattern with 5 interconnected oceans
• Surface currents along the western edge move
  poleward from tropics
• Along the eastern edge they move towards equator
• This pattern impelled by the wind and caused by
  coriolis effect, deflective force of earth
  rotation
• Northern and Southern variations
• Continents closer together in North
• More continuous flow in Southern Hemisphere

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http//ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/cr
ls.rxml
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Vertical Temperature Patterns

• Depends on Season, time of the day, cloud cover
  and other factors
• Laps rate(3.6 F/1000ft or 6.5 C/KM)
• Temperature Inversion
• Radiational (rapid cooling in high lat e.g.. cold
  nights inversion)
• Advectional (ocean to coast in winter)
• Cold-air drainage (cold air sliding down a
  valley)
• Upper air Inversion (high altitude)

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Adiabatic Heating/Cooling
Figure 4-15
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Global Temperature Patterns

• Seasonal extremes Jan and July
• Isotherms
• Control of temperature
• Altitude
• Latitude
• Land-water Contrasts
• Ocean Currents

• Seasonal patterns
• Annual temperature range

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Global Annual Temperature Range
Figure 4-34
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Spatial/Seasonal VariationsLatitudinal
Differences
Figure 4-18
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Land and Water ContrastsAnnual Temperature Curves
Figure 4-25
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Seasonal Latitudinal Shift
Figure 4-33
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People and the Environment

• Certain gases inhibit escape of LW radiation
• NCDC and IPCC are sources of info
• Average 0.6 C degree in 20th century
• Without natural green house effect earth would be
  30. Degrees C colder
• More Co2 because of humans (1. co2, 2. NxOX 3.
  Methane, 4. CFCs, 5. PFC ( Al-smelter), 6.
  sulphur hexafluoride (power insulation
  industry))
• Heat and draught more prevalent

• Computer modeling
• More data and evidence needed
• Kyoto Protocol
• US, china, Russia, Japan, Germany, India
• Cut by 5 by 2010
• More research needed
• Solar, hydro, wind, Nuclear energy are cleaner