What is Climate Change?
The evidence of climate change is overwhelming and scientists are clear that human activities are the cause.
What is Climate Change?
The earth's climate is changing. Globally, each of the last three decades has been the warmest on record and warming in the Arctic is occurring twice as fast as the rest of the world. The evidence of climate change is overwhelming and scientists are clear that human activities are the cause.
The Greenhouse Effect
- Solar energy from the sun passes through the Earth's atmosphere
- Some energy is reflected back into space
- The surface of the Earth is heated by the sun and radiates the heat back into space
- Greenhouse gases in the atmosphere trap some of the heat, warming the Earth
The earth is surrounded by a layer of naturally occurring gases known as its atmosphere, which includes water vapour, carbon dioxide, methane and nitrous oxide. These are commonly referred to as "greenhouse" gases because, like the walls of a greenhouse, they trap some of the heat from the sun and this warms the planet and makes it livable. Without these gases, the earth would be too cold to support life.
Over the past 150 years, humans have been releasing more and more greenhouse gases into the atmosphere, causing the blanket of greenhouse gases around the earth to thicken. This is preventing heat escaping into space and causing global temperatures to rise and climates around the world to change.
Global Greenhouse Gas Emissions
Globally, the three most common types of greenhouse gases (GHGs) that result from human activities are carbon dioxide, methane and nitrous oxide.1
Carbon Dioxide (CO2) - 76% of global GHG emissions
- Fossil Fuels - Whenever we burn fossil fuels (like coal, oil and gas) to create energy for our homes, business or vehicles, we send carbon dioxide into the atmosphere.
- Deforestation - Trees naturally store carbon dioxide. When we cut down trees to clear space for new buildings, or to create space for agriculture, we send carbon dioxide into the atmosphere.
Methane (CH4) - 16% of global GHG emissions
- Waste - Humans create a lot of waste. Over 30% of this waste is organic material, like food scraps. When buried organic material decays in a landfill, it releases methane.
- Livestock - Animals are reared to create food for humans. Cows, sheep, goats and other animals create methane as part of their normal digestive process. As a result, livestock is the main source of human-caused methane emissions worldwide.
Nitrous Oxide - 6% of global GHG emissions
- Fertilizers - Farmers use fertilizers to provide nutrients to crops. Synthetic (i.e. man-made) fertilizers release nitrous oxide when they break down. Fertilizers that are used for agriculture are the main source of nitrous oxide emissions worldwide.
- Transportation - Nitrous oxide is produced as a byproduct when fuels are burned to power motor vehicles. The amount of nitrous oxide that's produced depends on the type of fuel and the vehicle's technology.
Find out more in GHG emissions in Newfoundland and Labrador.
To see how GHG emissions are driving global climate change compared to other factors (like the sun and volcanic activity), see this interactive data visualization prepared by Bloomberg using findings from NASA’s Goddard Institute for Space Studies.
So what does this mean for our planet?
The Intergovernmental Panel on Climate Change, is the global authority on climate change science. It has found that the planet has warmed by 0.85°C since 1900 and temperatures could rise by up to 4.8°C by the late 21st century if GHG emissions do not decline. Such increases in temperature could have a catastrophic impact on climates throughout the world.
Find out more about the impacts of climate change on Newfoundland and Labrador.