The Atmosphere

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The Atmosphere
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• Atmospheric Objectives
• Students will learn how the Earths atmosphere
  is structured
• by observing its layers, temperature
  variations, and
• distribution of atmospheric pressure.
• Students will learn how air parcels circulate
  within the
• Earths atmosphere, creating wind
• Students will understand the nature of
  insolation entering
• the Earths atmosphere, specifically the
  impact of ultraviolet
• radiation on various types of material.
• Students will gain insight regarding the global
  warming
• debate.

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• Thermosphere
• Begins at 80 km (50 miles)
• Temperatures as high as
• 12000C

• Mesosphere
• 50-80 km (31-50 miles)
• atmosphere thins rapidly
• coldest layer ? - 900C

T

• Stratosphere
• 11 km 50 km (7-31 miles)
• 20 of the atmospheric
• weight
• Contains the ozone layer
• (lower stratosphere)
• Temperatures increase with
• altitude

T
T

• Troposphere
• 11 km thick (7 miles)
• 80 of the atmospheric
• weight
• All storm activity takes
• place
• environmental lapse rate
• 6.50C/1000 m

T
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• Atmospheric Pressure
• Force/unit area exerted against
• a surface
• Represents the weight of the
• atmosphere
• Uniformly decreases with altitude
• However --NOT uniform
• across the entire earth
• Analogous to boiling water

Thinning Air Molecules
Low Pressure
Decreasing Pressure
Air masses rise and fall within the
atmosphere. Dependant on the
cooling/heating of the Earths surface
High Pressure 14.7 psi (1013 mb)
Cooling air sinking air High
Pressure Warming air rising air Low
Pressure
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What causes high and low pressure zones ??

• High Pressure
• Cold sinking air

• Low Pressure
• Warm rising air

Anticyclone
Cyclone
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• Wind - What is it?
• Unbalanced air pressures
• High air pressure moves into low
• pressure systems

Cooling descending air parcel
Rising ascending air parcel
High Pressure
Low Pressure
High pressure air rushes to fill the void left
by rising the rising air parcel
Warm Land
Cooler Water
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isobar

• Pressure Gradient Force
• primary force that causes wind
• always drawn perpendicular to isobar lines.

Isobars equal points of pressure
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Producing an Isobar map
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What is light? (insolation)
Light is a form of electromagnetic radiation,
vibrating electric and magnetic fields moving
through space.
wavelength
Insolation (light from the sun) is measured using
wavelength
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• What is incoming solar radiation? (insolation)
• energy the earth receives from the sun
• travels 300,000 km/sec (186,000 mi/sec)
• travels in wave motion
• Sun rays comprise the electromagnetic spectrum.

Electromagnetic Spectrum (EM scale)
Wavelengths the human eye can see R O Y
G B I V
Very harmful
Not harmful
Short Waves
Long Waves
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Visible light spectrum Is separated into the
various ROYGBIV wavelengths
Visible light spectrum passing through a
glass prism
Glass Prism
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insolation
Thermosphere
most short waves are absorbed
Mesosphere
OZONE
Stratosphere
UV waves are absorbed and make ozone (O3)
Troposphere
Most EM is longwave before hitting the
surface (visible and IR)
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UV
97 of UV radiation absorbed 3 of UV radiation
makes to the Earths surface.
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• Todays Lab take a deep breath
• Complete part A
• definitions definitions can be found in the
• lab text READ IT
• Complete part B
• Complete the diagram by illustrating the layers
  of the
• atmosphere use colored pencils
• Complete the US isobar map (USE PENCIL!
• Complete part C
• Acquire the UV detecting beads and follow the
  instructions
• outlined in part C
• Complete part D
• Read the lab text and answer questions regarding
  
• the greenhouse effect and the relation to
  global warming.