Weather hazards and climate change

• What major fluctuations in temperature have occurred during Earth's history?

  Colder glacial periods and interglacial periods
• What has been the trend in Earth's climate over the last few hundred years?

  The climate has been warming rapidly
• By how much has the average temperature increased since the 1880s?

  0.85°C
• When did most of the temperature increase occur since the 1880s?


  Since the 1970s
• What is one natural cause of climate change?

  Solar output variations
• What is the sunspot cycle?

  An 11-year cycle where the number of sunspots varies from a minimum to a maximum
• How does the sunspot cycle relate to Earth's climate?

  Temperature changes on Earth relate to solar output
• What is a volcanic winter?

  A reduction in Earth's surface temperatures due to volcanic eruptions
• How can volcanic eruptions affect Earth's temperature?

  By blocking out the sun with ash and gases
• What happens to ash from volcanic eruptions in the atmosphere?

  Larger amounts can block out the sun, causing short-term cooling
• What is the effect of sulphurous gas emitted by eruptions?

  It reacts to form aerosols that reflect solar radiation
• What is the greenhouse effect?

  It is the trapping of heat by greenhouse gases in the atmosphere
• How does solar radiation affect the Earth's surface?

  It heats up the surface of the Earth
• What happens to heat when the Earth cools?

  Some heat leaves the atmosphere into space
• What role do greenhouse gases play in the Earth's temperature?

  They trap some heat, keeping the Earth warm