week 11

• What is the first topic in the lecture structure?

  Climate change information sources
• How does the atmosphere affect climate?

  Through the greenhouse effect and albedo
• What are the components of the greenhouse effect?

  • Greenhouse gases (GHGs)
  • Short-wave solar radiation
  • Long-wave radiation (heat)

  
• What gases are considered greenhouse gases?

  Methane, carbon dioxide, water
• What is the greenhouse effect necessary for?

  Life on Earth
• What are the sources of greenhouse gases?

  • Volcanic activity
  • Decay of organic matter
  • Respiration
  • Fossil fuel burning
  • Deforestation
  • Agriculture
• What are the sinks of greenhouse gases?

  • Anaerobic decay and burial
  • Carbonate rock burial
  • Silicate rock weathering
  • Photosynthesis
  • Dissolution in oceans
• How do sources and sinks affect atmospheric GHG levels?

  They control the balance of GHG levels
• What does albedo refer to?

  Reflection of solar radiation from surfaces

  
• What are the two types of aerosols mentioned?

  Black and white aerosols
• What effect do sulphate particles have on the atmosphere?

  They scatter radiation, cooling the atmosphere
• What are the main anthropogenic sources of CO2 emissions?

  • Coal burning
  • Methane combustion
  • Propane combustion
  • Cement making

  
• What percentage of total GHG emissions is CO2 from fossil fuels and industry?

  78%
• What is the main natural sink for CO2?

  Plants and forests
• How much CO2 has the ocean absorbed since emissions began?

  About 30%
• How do we know the extra carbon in the atmosphere is from fossil fuel burning?

  By comparing atmospheric CO2 and emissions

  
• What isotopes of carbon are used to identify fossil fuel carbon?

  Heavy 13C and light 12C
• When did continuous CO2 measurements start at Mauna Loa?

  1958

  
• What significant CO2 level was surpassed on May 9, 2013?

  400 ppm
• What trend is observed in global temperature from 1880 to 2012?

  Linear trend of +0.85°C
• What caused the mid-20th Century pause in temperature increase?

  Increase in sulphate aerosols
• What is the rate of sea-level rise from 1993 to 2010?

  1. 2 mm/year
• What percentage of sea-level rise is attributed to melting ice?

  50%
• What has happened to ocean acidity since the industrial revolution?

  Increased by 26%
• What environmental change is likely since about 1950?

  Increased number of warm days
• What is likely to have increased over land in more regions?

  Heavy precipitation events
• What is the confidence level for sea-level change before 1901?

  Medium confidence
• What is the confidence level for sea-level change after 1951?

  High confidence
• What is the global mean sea-level rise from 1901-2010?

  0.19m (0.17-0.21m)

  
• What was the rate of sea-level rise from 1993-2010?

  1. 2 (2.8-3.6) mm/yr
• What was the rate of sea-level rise from 1901-2010?

  1. 7 (1.5-1.9) mm/yr
• How does the rate of rise since the mid-19th century compare to the last 2000 years?

  It exceeds the mean rate of rise
• What percentage of sea-level rise is attributed to melting ice according to IPCC AR5 (2014)?

  50%
• What percentage of sea-level rise is attributed to thermal expansion according to IPCC AR5 (2014)?

  50%
• By how much has the pH of ocean water decreased?

  0.1 C
• What is the increase in acidity of ocean water?

  26%
• What is very likely to have happened to the number of cold days and nights since 1950?

  They have decreased
• What is likely to have happened to the number of warm days and nights since 1950?

  They have increased
• What is likely regarding heavy precipitation events over land?

  They have increased in more regions
• What is the confidence level in large-scale trends in storminess over the last 100 years?

  Low confidence