What is CO2 and why is it important for climate change?

Weather Presenter Aisling Creevey explains why Carbon Dioxide is important in the atmosphere and why we need to monitor it

Carbon Dioxide, also commonly referred to as CO2, is one of the many naturally occurring gases in our atmosphere. These so-called Greenhouse gases are vital for sustaining life on earth.

Scientists can work out what the atmosphere was like going back thousands of years through ice core samples. They show a marked increase in the amount of CO2 in the atmosphere we live in today, versus the atmosphere before the industrial revolution.

Gases being produced by industry

Met Office research tells us that our atmosphere now contains about 45% more CO2 than it did before the Industrial Revolution, causing the earth to warm at an unnatural rate. Some parts of the earth are warming quicker than others with the poles warming three times as fast as the rest of the planet.

Science research tells us that Carbon dioxide levels today are higher than at any point in the past 800,000 years. In fact, the last time the atmospheric CO2 amounts were this high was more than 3 million years ago, during the Mid-Pliocene Warm Period, when temperature was 2°–3°C higher than during the pre-industrial era, and sea level was 15–25 meters higher than today.

Carbon Dioxide over the last 800,000 years Credit: NOAA Climate Services

Climate scientists at NASA state that man-made CO2 in the atmosphere, stays for a very long time, between 300 to 1000 years. This means the C02 from the industrial revolution is still in the atmosphere as is all the other C02 produced since then.

This is why carbon CO2 is a very important indicator of global warming.