Climate

• Ice age

  When earth cooled and ice sheets and glaciers spread
• Quarternary period

  Period from 2.6 million years ago
• Ways to look at past climates

  Ocean sediment, radiometric dating, ice sheets, tree rings
• Ocean sediment

  Builds up many layers over millions of years. The core of sediment is drilled from the ocean floor
• Radiometric dating

  Each layer is studied. It tells both the age of the layer and the climate back then
• Ice sheets

  Builds up from layers of snow. Analysis of ice cores show when the snow fell and temperature and the gases in the air
• Tree rings

  Number of rings is the trees age. Width tells us the climate
• Factors that influence climate change

  Changes in Earth's movement in space, changes in suns output, volcanic eruptions, human activities
• Milankovitch cycle

  Changes in Earth's movements, which affect the climate
• Impacts of climate change

  Floods, wildfires, drought, heatwaves, less crop yield, pests
• Increase in Carbon dioxide

  Less vegetation is absorbing trees as we cut them down
• Increase in methane

  Cows, sheep, goat and other animals that chew the cud. Given off in swamps, paddy fields and landfill sites
• Ways to cut emissions

  Wind farms, solar farms, wave and tidal power plants, electric vehicles, artificial meat
• Countries agreed to reduce emissions in treaties called Kyoto protocol and Paris agreement
• Greenhouse gas

  Gases that trap heat and warm up the Earth
• Albedo effect

  When the ice melts, the ground warms up, because the darker surfaces absorb more sunlight
• Carbon neutral

  Adding no extra carbon dioxide to the atmosphere