What is carbon dioxide?
What is the gas playing a key role in climate change?
Carbon dioxide is a colourless and odourless gas which occurs naturally in the earth’s atmosphere. It is often known by its chemical symbol CO2.
How is carbon dioxide formed?
Carbon is the basis of life on earth. It is found in almost everything on our planet. Because the earth has a closed atmosphere, the same amount of carbon has always been present. We find it in the oceans, in the soil beneath our feet, and in the living things that surround us.
Carbon dioxide is formed when one carbon atom meets two oxygen atoms. This can happen in a number of ways, for example as organic matter decays or when animals and humans breathe and even when volcanoes erupt. It also happens when organic matter that contains carbon is burned. For instance, natural gas, coal or wood.
How are rising carbon dioxide levels affecting our planet?
CO2 is a greenhouse gas (GHG). It helps prevent heat escaping from the atmosphere. This is one of the reasons that earth is not too cold for life. However, a rapid increase in the amount of carbon dioxide and other GHGs in the atmosphere is leading to temperatures rising around the world and to climate change.
Since the start of the Industrial Revolution at the beginning of the nineteenth century, there has been an enormous increase in atmospheric levels of carbon. They currently stand at 387 parts per million — a rise of 39%.
That is the highest level there has been in the last 800,000 years.
What can we do to reduce CO2 levels?
There are many ways we can reduce the levels of carbon dioxide in the earth’s atmosphere. For instance, we can reforest. We can also generate energy in ways that don’t depend on burning fossil fuels.
Widely available sources of energy, such as biomass, hydro, solar and wind, can all give us sustainable and carbon-neutral electricity.
Innovative technologies such as carbon capture and storage (CCS) can permanently store CO2 from industries which are still emitting carbon. And it is even possible to generate electricity with negative emissions through Bioenergy with carbon capture and storage (BECCS). This process will result a greater amount of carbon dioxide being removed from the atmosphere than is emitted during the generation process.
CO2 — the facts
The growth rate of the carbon dioxide level in the atmosphere has increased almost fourfold since the 1960s to 2.3 parts per million per year.
Forests can play a crucial role in helping to prevent potentially catastrophic climate change. In the United States, they absorb 13% of the country’s carbon output.
