The%20Earth%20and%20Its%20Atmosphere:%201.%20Vertical%20structure%202.%20Weather%20and%20climate

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The Earth and Its Atmosphere1. Vertical
structure2. Weather and climate
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Mass,Weight, Density, Pressure

• Mass M
• property of matter,
• SI unit kg. Other units 1kg1000 g, 1
  lb450 g
• Weight
• a force, has a magnitude and direction (vector).
• weight mass x gravity g(Earth)
  9.78 m/s2
• SI unit kg m/s2 -gt N g(Mars)
  3.7 m/s2
• Density r
• mass per unit volume density mass / volume
• SI unit kg/m3, Other g/cm3
• Pressure p
• p force/area
• SI units PaN/m2, Other 1bar100 Pa

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Atmospheric pressure
Atmospheric pressure and density decrease with
altitude exponentially!!!
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RECAP

• Atmospheric composition
• Permanent gases N2, O2, Ar, Xe, Ne, H2, He
• Variable gases CO2,H2O,O3,CH4
• Greenhouse gases H2O, CO2, NO,CH4
• Mass.
• Weight.
• Density.
• Pressure.
• The atmospheric pressure and
• density decrease with altitude.

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Mid-chapter brief review(s)

• The earths atmosphere is a mixture of many
  gases. In a volume of dry air near the surface,
  nitrogen (N2) occupies about 78 percent and
  oxygen (O2) about 21 percent.
• Water vapor, which normally occupies less than 4
  percent in a volume of air near the surface, can
  condense into liquid cloud droplets or transform
  into delicate ice crystals. Water is the only
  substance in our atmosphere that is found
  naturally as a gas (water vapor), as a liquid
  (water) and as a solid (ice).
• Both water vapor and carbon dioxide (CO2) are
  important greenhouse gases.
• Ozone (O3) in the stratosphere protects life from
  harmful ultraviolet (UV) radiation. At the
  surface, ozone is the main ingredient of
  photochemical smog.
• The majority of water on our planet is believed
  to have come from its hot interior through
  outgassing.
• Atmospheric pressure at any level represents the
  total mass of air above that level, and
  atmospheric pressure always decreases with
  increasing height above the surface.

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Vertical Structure of the Earths Atmosphere
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Atmospheric layers(according to the temperature)

• Troposphere
• The temperature T decreases with height at a rate
  of 6.5 K/km.
• Well mixed as a result of turbulence and
  convection
• Weather phenomena
• Tropopause
• Isothermal (T constant)
• Located 8-15 km above the ground.
• Stratosphere
• The temperature T increases with height
• O3 layer at 25 km altitude
• The atmosphere is very stable
• Stratopause Tconst
• Mesosphere
• T is decreasing with height effective cooling
  through IR emission
• Very unhealthy region hypoxia (oxygen
  deprivation), UV burns, blood begins to boil
• Mesopause the coldest region on Earth.
• Thermosphere fast T increase. Diffusive
  separation of gases.

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Atmospheric layers other classifications

• Mixing
• Homosphere
• well mixed,
• the chemical composition is constant.
• Heterosphere
• no turbulence and mixing,
• diffusive separation of gases
• Ionization
• Ionosphere part of the atmospheric gas is
  ionized through photo ionization or impact
  ionization.
• (talk about the atom)

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Weather/ Climate

• Weather elements
• Air temperature thermometer (C, F, K)
• Air pressure barometer (bar, mbar)
• Humidity hygrometer ()
• Wind (m/s , km/h, mi/h)
• Clouds
• Precipitation
• Visibility
• Weather the daily variations of the atmospheric
  conditions. It is partly cloudy today, with a
  50 chance of rain
• Climate average weather. The average maximum
  temperature for the month of January is 35 F.

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Weather Forecasting Using Satellites
isobar
streamline
isotherm
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The World
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Jupiter as seen from Cassini
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Jupiter
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Meteorology a brief history

• Meteorology is the study of the atmosphere and
  its
• phenomena
• In Meteorologica (340 B.C.) Aristotle discussed
• meteors (things which fall from the sky)
• weather and climate, astronomy, geography
• clouds, rain, snow, wind, hail, thunder,
  hurricanes
• Invention of weather instruments in the Middle
  Ages
• Pressure barometer (1643, E. Torricelli)
• Humidity hygrometer (1783, H. de Saussure)
• Rapid exchange of weather information (telegraph,
  1843)
• Crude weather maps (1869)
• Norwegian model of storm development (1920s)
• Air balloon and high-flying aircraft observations
  (1940)
• High-speed computers and numerical predictions
  (1950-)
• Weather satellites (1960-)

Aristotle
de Saussure
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Simplified surface weather map
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Weather phenomena a preview
Clouds and thunderstorms
Ice storm
Tornadoes
Flooding