When two Englishmen meet the first thing they talk about is the weather

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Weather and the Environment

• When two Englishmen meet the first thing they
  talk about is the weather
• Dr Johnson

David Leadley P544
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Weather and Climate

• Weather / meteorology study of atmosphere and
  atmospheric processes, daily variation
• Climate / climatology seasonal average of
  weather at some location
• Climate change long term variation in climate

and the environment
Environment conditions for life or
growth Sustainability ability of the
environment to function indefinitely, despite
stresses imposed by human society
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Non-sustainable Human behaviour

• Using non-renewable resources as if supplies were
  unlimited eg. fossile fuels
• Using renewable resources faster than they can be
  replenished eg. fresh water
• Polluting the environment as if its capacity were
  unlimited eg. CFCs, CO2, acid rain
• Increasing population, despite Earths finite
  ability to support us

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Earth from the Space Shuttle
For the first time in my life I saw the horizon
as a curved line. It was accentuated by a thin
seam of dark blue light our atmosphere. I was
terrified by its fragile appearance.
Ulf Merbold, astronaut
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Components of the climate system

• Atmosphere Greek for vapour ball
• Hydrosphere oceans
• Cryosphere snow and ice fields
• Biosphere life and human influence

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Composition of the Atmosphere(1) Permanent Gases
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Composition of the Atmosphere(2) Variable Gases
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Origin of the atmosphere

1. Earth formed 4.6 billion years ago, without
   atmosphere
2. Outgassing from volcanoes of N2, CO2, H2O, H2,
   Cl2, SO2, CH4 , but not oxygen
3. Water condensed in oceans, H2 escaped, acid rain
   weathered rocks.CO2 at 100 times present level
   larger greenhouse effect kept the atmosphere
   warmer and compensated for a 30 weaker Sun
4. Emergence of life in oceans produced O2 and
   sequestered CO2 in rocks
5. Once O2 was present O3 could be formed,giving UV
   protection and allowing life to expand its range

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Atmospheric Oxygen
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Albedo from various surfaces
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Planetary temperature profiles
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Atmospheric profile of Venus
At surface Ts740 K ps92 bar
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Atmospheres of Gas Giants
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Titans Atmosphere

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Summary of Lecture 1

• Introduction to Earths atmosphere
• origin
• composition
• structure
• comparison with other planets
• Stefans law