Carbon Dioxide
What is COâ‚‚, and why does it matter?
Carbon dioxide (COâ‚‚) is a greenhouse gas — it traps heat in Earth’s atmosphere.
Think of it like a blanket around the planet: a little keeps us warm, but too much makes things overheat.
As we burn fossil fuels, we add more COâ‚‚ to the air. This thickens the blanket and warms the planet — a key driver of climate change.
Let’s look at how COâ‚‚ levels have changed over time.
The Keeling Curve - A Historical Look
This chart shows the amount of carbon dioxide (COâ‚‚) in Earth’s atmosphere, measured at Mauna Loa Observatory in Hawaii since 1958. It’s known as the Keeling Curve, named after scientist Charles David Keeling, who started the measurements.
The curve rises year after year, showing a steady increase in COâ‚‚ levels — from around 315 parts per million (ppm) in 1958 to over 420 ppm today. That’s a more than 30% increase in just a few decades.
The Keeling Curve is one of the clearest pieces of evidence that human activities — especially burning fossil fuels — are changing the makeup of our atmosphere and driving climate change.