geo guide

• Enhanced greenhouse effect


  The magnified greenhouse effect caused by high increases in the amount of CO2 and other greenhouse gases in the atmosphere
• Carbon dioxide (CO2) in the atmosphere works just like the glass in a greenhouse, letting the Sun's rays through but retaining the heat
• CO2 is one of the greenhouse gases
• The greenhouse effect created by nature is called the natural greenhouse effect
• Because of high increases in the amount of CO2 and other greenhouse gases in the atmosphere, the effect created by nature is magnified, which we call the enhanced greenhouse effect
• Since 1850, the average temperature worldwide has increased by about 0.8°C
• Fossil fuels


  Fossil energy sources formed over millions of years from the remains of dead plants, trees and animals, used as fuel for transportation, heating, and electricity generation
• Higher CO2 emissions are mainly caused by the burning of natural gas, petroleum and coal, which are fossil fuels
• Climate change


  Changes in the Earth's climate seen over long periods of time
• The Earth experienced the 'Little Ice Age' between 1400 and 1850, when it was colder and there was more snow, and the average temperature is now one to two degrees higher
• The temperature increase over the past 150 years is striking, while over millions of years, cold periods (ice ages) alternated with warm periods (interglacial periods)
• The big difference between global temperature increases millions of years ago and today is that today human activity is partly responsible for climate change, which is why it's called the enhanced greenhouse effect
• Scientists hope the extra temperature increase will remain below 1.5 to 2°C by the end of the 21st century, but the climate feedback loops can have an enormous impact on nature
• Albedo


  The amount of sunlight and heat reflected back from the Earth's surface
• A blanket of snow or layer of ice reflects back as much as 80% to 95% of the heat radiation from the sun, while dark surfaces absorb heat
• Positive climate feedback loop


  A feedback loop that accelerates or increases climate change, such as the albedo effect
• Negative climate feedback loop

  A feedback loop that decelerates or decreases climate change, such as water vapour and cloud feedback
• Sea levels are rising due to the melting of land ice in areas such as Greenland and Antarctica, as well as the expansion of warmer oceans
• The climate is becoming more extreme, with more water damage from flooding or water shortages and droughts, which can lead to the spread of deserts and have consequences for agriculture and landscape zones
• As the Earth gets warmer, the thawing and rotting of frozen remains in the permafrost releases methane, a powerful greenhouse gas that accelerates global warming