Geography Climate Change+Greenhouse effect

• Weather


  Atmospheric conditions of a place over a short period of time
• Climate


  Average weather conditions of a place over a long period time
• Climate of Hong Kong


  • Located near the Tropical of Cancer, has a subtropical climate
  • Affected by the monsoon system
• Summer monsoon


  1. Prevailing wind blows from southeast and southwest

  2. Land absorbs heat faster than the ocean, causing low pressure at land and high pressure at sea

  3. Wind blows from sea to land
• Winter monsoon


  1. Prevailing wind blows from northwest

  2. Land loses heat faster than the ocean, causing high pressure at land and low pressure at sea

  3. Wind blows from land to sea
• The climate of Hong Kong is affected by the monsoon system
• Monsoons are winds that change direction regularly
• Land temperature


  Higher than sea temperature
• Land pressure


  Lower than sea pressure
• Wind direction


  Blows from high pressure to low pressure
• Seasons


  • Spring
  • Autumn
  • Summer
  • Winter
• Temperature


  Warm in spring and autumn, hot in summer, cold in winter
• The annual mean temperature of Hong Kong has been rising, and the rate of increase has become faster
• Extreme rainfall events are also occurring more frequently in Hong Kong
• Increase in temperature


  Decrease in cloud amount, urban wind speed, and visibility
• Decrease in wind speed


  Decrease in ability to blow away air pollution
• Decrease in cloud formation


  Decrease in precipitation
• The distribution of temperature is uneven in the world, decreasing with increasing latitude
• Regions near the equator have the highest annual mean temperatures, whereas the polar regions are lower
• The world is divided into three temperate zones: tropical, polar and temperate zones
• Regions along the equator receive an abundant annual rainfall, while deserts, inland areas, and high-latitude regions are dry
• In other parts of the world, rainfall is often seasonal
• In recent decades, both global mean temperature and rainfall have shown rising trends
• Many parts of the world have had fewer cold days and cold nights but more hot days, hot nights and heat waves
• High-latitude regions have experienced greater temperature rises
• Increase in greenhouse gases

  Increase in global mean temperature
• Increase in global mean temperature


  Increase in global mean rainfall
• Regional rainfall has become more extreme, with many places experiencing more extreme rainfall events
• The Northern Hemisphere is hit by stronger thunderstorms and typhoons
• Regions such as the Sahel in Africa have become drier
• Greenhouse effect


  A natural process where gases in the atmosphere absorb and trap heat, keeping the Earth warm
• Global warming


  Increase in global temperature due to enhanced greenhouse effect caused by human activities
• Climate change


  Significant long-term changes in climatic patterns caused by natural processes and human activities
• The Intergovernmental Panel on Climate Change projects that by the end of the 21st century, the global mean temperature is likely to increase by more than 1.5°C
• Global rainfall patterns will become more extreme with larger regional differences
• High-latitude regions may receive more rainfall, while some mid-latitude and low-latitude regions may receive less rainfall
• Extreme rainfall events may also become more intense and occur more frequently
• Human activities that cause climate change


  • Use of fossil fuels
  • Farming activities
  • Industrial activities
  • Waste management
• Use of fossil fuels


  • Emit a lot of greenhouse gases
  • Mostly used for power generation and transport
• Farming activities


  • Deforestation to open up farmland reduces carbon sinks
  • Burning vegetation to improve soil fertility releases CO2
  • Commercial pastoral farming emits methane and nitrous oxide
  • Use of fertilizers releases nitrous oxide