week 10

• What are the tropical climates restricted to?

  25N & S
• How is precipitation controlled in tropical climates?

  By the Intertropical Convergence Zone (ITCZ)
• What is a monsoon?

  Seasonal wind reversal
• What drives the Asian monsoon?

  Thermal gradient between ocean and landmass
• What is the difference between summer and winter in the Asian monsoon?

  Summer is wet; winter is dry
• How does geography affect the monsoon's impact?

  It varies by location
• What does the Southern Oscillation describe?

  A pressure difference between E and W Pacific
• What do El Nino and La Nina refer to?

  Changes in water temperature off W South America
• What happens during El Nino?

  Warm water spreads across the Pacific
• What characterizes La Nina?

  Cold water off S America and strong easterly winds
• What does the Southern Oscillation Index measure?

  Pressure difference between Tahiti and Darwin
• How is the equatorial Pacific Ocean monitored?

  By an array of moored instruments
• What is the composition of today's atmosphere below 25 km?

  • Nitrogen: 78%
  • Oxygen: 21%
  • Argon: 0.9%
  • Ozone: 0.000004%
  • Trace gases: CO2, CH4, N2O, etc.

  
• What is the historical significance of coal use in London in 1273?

  Coal use was prohibited for health reasons
• What was the impact of the Industrial Revolution on air pollution?

  Urban pollution reached record highs
• What did the 1806 report about Leeds indicate?

  Leeds was a dirty, smoky town
• What was the purpose of the Royal Commission on Noxious Vapours in 1876?

  To investigate industrial air pollution
• What happened during the Great London Smog of 1952?

  Visibility reduced; 4000 deaths occurred
• What legislation resulted from the Great London Smog?

  The Clean Air Acts of 1956 and 1968
• What changes have occurred in air pollution since the 1950s?

  Population and cars have increased
• What are primary air pollutants?

  Emitted directly from identifiable sources

  
• What are secondary air pollutants?

  Produced by chemical reactions in the atmosphere
• What are examples of point sources of pollution?

  Factories and power plants
• What are mobile sources of pollution?

  Transport like cars and planes

  
• What is particulate matter?

  Mixture of particles suspended in air
• What does PM2.5 refer to?

  'Fine particles' with diameter ≤ 2.5 micrometres

  
• What is the main source of sulphur dioxide?

  Combustion of sulphur-containing fossil fuels
• What happens to sulphur dioxide in the atmosphere?

  Transforms to sulphuric acid
• What are nitrogen oxides (NOx)?

  Gases formed during high-temperature combustion
• What is the main source of volatile organic compounds (VOCs)?

  Incomplete combustion of gas in vehicles
• What is the most abundant VOC?

  Methane (CH4)
• What are the types and sources of air pollutants?

  Types:

  • Primary pollutants: emitted directly
  • Secondary pollutants: formed by reactions

  
  

  Sources:

  • Point sources: factories, power plants
  • Mobile sources: transport
  • Biogenic sources: volcanoes, pollen
  • Area sources: clusters of small sources

  
• What are the trends and patterns of air pollutants emission?

  • Increased regulations since the 1950s
  • Population and vehicle numbers have risen
  • Types of pollutants have evolved
  • Problem countries have shifted
• What does de combine with to form acid rain?

  Water
• What are the products of the reaction between 2NO2 and H2O?

  HNO2 and HNO3
• What are volatile organic compounds (VOCs)?

  Hydrocarbons composed of hydrogen and carbon
• What is the most abundant volatile organic compound?

  Methane (CH4)
• What is the main source of VOCs?

  Incomplete combustion of gas in vehicles
• How do VOCs interact with other pollutants?

  They form secondary pollutants
• What is carbon monoxide (CO)?

  A colourless, odourless, poisonous gas