Atmosphere

• What holds the atmosphere in place?

  Gravity
• Nitrogen = 78%

  Oxygen = 21%

  Carbon dioxide = 0.04%

  Rare gasses = 1%

  Ozone = 0.000007%
• What two processes work together to form a dynamic equilibrium to keep the atmosphere stable?

  Aerobic respiration and photosynthesis
• The ozone layer is made out of monotomic, diatomic, and triatomic oxygen molecules. It is located in the stratosphere.
• What is the electromagnetic biologically damaging radiation from the sun called?

  Solar wind
• Mainly the tropical regions are heated by the sun's energy, this warm surface heats the atmosphere and then is blown to higher latitudes by warm winds. Such as the south westerly winds that heat the UK from the Caribbean.
• How do ocean currents support life?

  The winds blow warm water towards colder area such as the north Atlantic conveyor.
• Winds transport water vapor to area that otherwise wouldnt get as much precipitation.
• Atmospheric pressure controls the ease that which water molecules can evaporate and escape.
• What are the first 2 layers of the atmosphere?

  Troposphere and Stratosphere
• The electromagnetic radiation arriving at earth are mainly short wave, UV light. The electromagnetic radiation re-radiated from earth is usually in the form of long wave infrared radiation.
• Aerosols scatter light and reduce visibility but also absorb solar radiation so they have warming effects on climate.
• Ozone absorbs ultraviolet radiation from the sun. This protects living organisms on Earth from damage caused by UV rays.
• What part of the amosphere is warmed by the natural greenhouse effect?

  The troposphere
• If there was no natural greenhouse effect the earths temperature would be 33 degrees colder than it is now.
• GCC involves changes to the composition of the atmosphere that alter energy processes, the climate and the physical and biological processes they can control. Changes resulting from human activity are known as anthropogenic changes.
• The main greenhouse gasses are: Carbon Dioxide, Methane, Nitrous Oxides, chlorofluorocarbons and tropospheric ozone.
• Ecological changes due to altered abiotic factors:

  • directly affected by temperature
  • Temp may cause plants to grow faster (provide more food)
  • Precipitation may cause wetlands to shrink or enlarge
  • Trees with deep roots will survive better than those without
  • Hibernating animals may be woken earlier and not survive
  • Time of ecological events may be wrong such as migration
• The species most likely to be affected are those that are closest to their range of their tolerance
• Increased global temperatures is causing the jet streams to meander in rosby waves causing more extreme weather events for longer.
• The increased global temps cause more evaporation which increases rainfall in the same or different areas. This may cause more droughts or floods.
• Changes in the cryosphere due to GCC:

  • Reduction on the snow cover
  • changes in extent and speed of land ice
  • loss of ice shelves
  • changes in thickness and area of ice
  • ice lakes
  • ice and snow fed rivers
• What are the two main cause of sea level rise?

  • Thermal expansion of sea water
  • Melted sea ice
• The three case studies for sea level rise are: Kiribati, Bangladesh and the Maldives.
• The north Atlantic conveyor belt is a current of warm water that flows from the Gulf of Mexico to the North Atlantic and heats alot of northern and western Europe.
• El nino is a warm water current that flows from the pacific ocean to the atlantic ocean. This can be reversed and is then called la nina
• The gulf stream is slowing down and may shut down due to the melting fresh water in the arctic ocean making the water is dense so sinks less and doesn't need replacing by the warm Caribbean water
• CFC's were banned by the Montreal protocol in 1987 but they still exist in the atmosphere because they have long lifetimes.
• La Nina is when there is an increase in trade winds causing cooler waters in the eastern Pacific Ocean and warmer waters in the west. The opposite of El Nino.
• Ozone depletion occurs when chlorine atoms react with ozone molecules breaking them apart into oxygen
• The ozone hole was discovered over Antarctica in 1985
• Impacts of climate change on society:

  • Health - GCC can have many impact on human health such as respiratory conditions, worsening of existing conditions and heat stroke.
  • Water supplies
  • Food supplies
  • Impacts on infrastructure
• Methane is produced through natural processes such as decomposition and volcanic eruptions or human activities like agriculture and fossil fuel burning
• Anthropogenic greenhouse gas emissions come mainly from burning fossil fuels (coal, oil and natural gas) and deforestation.