CO₂ levels are rocketing up.

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• The orange line shows how the level of “carbon dioxide in our air” has moved over the last 400,000 years.
• Before 1950, CO₂ levels moved between :
  • Lows near 180 parts per million (ppm) during ice ages, and
  • Highs near 300 ppm.
• The CO₂ level in 1960 was about 317 ppm.
• The average CO₂ level in 2025 was 425.7 ppm. This level is 42% above the previous high of 300 ppm.
• The CO₂ level is going up like a rocket.

See the latest carbon dioxide graph. (Click on “Learn more” under the carbon dioxide graph)

This Climate Dot US website reproduces trusted climate information that was once available on US government websites. The Trump administration fired climate scientists and trashed these government sites. These scientists created this website.

It shows the average Carbon dioxide level in 2025 was 425.7 parts per million.

The CO₂ levels are rising faster.

In the 1960s, the increase in CO2 concentration was about one ppm per year. By 2006, the increase was about 2 ppm per year and getting larger. It may soon be three ppm per year.

(Atmospheric CO₂ is accumulating faster than ever: New Scientist, 2006)

If CO₂ continues to increase at the conservative rate of 2.0 ppm per year, it will reach 571 ppm by 2100.

Carbon dioxide levels are alarming.

Over the last hundred years, humans have burnt vast amounts of coal, oil, gas, and wood. This burning has released enormous amounts of carbon dioxide (CO₂) into our atmosphere.

Now we know that carbon dioxide is a greenhouse gas and acts like a blanket over the planet. It limits the amount of radiant heat that escapes into outer space, thereby warming the Earth. We also know that global temperatures and carbon dioxide levels have moved together for the past 400,000 years. So the current high carbon dioxide levels pose a threat of a substantial increase in temperatures and sea levels.

Carbon dioxide levels above 400 ppm occurred during the Pliocene, which extended from 5.3 to 2.6 million years ago. During this period, the sea level was about 25 metres higher than it is today.

Our species has never experienced such high levels of CO₂

The concentration of CO₂ in our atmosphere is already far above any level experienced over the past 800,000 years. Our species, Homo Sapiens, emerged about 250,000 years ago. The species from which we evolved, Homo Erectus and Homo Neanderthalensis, emerged about 400,000 years ago.

Our species, and the web of life that supports us, evolved with CO₂ levels between 180 and 300 ppm. They have never experienced CO2 concentrations at 409 ppm, let alone the forecast levels. If we allow these high levels of CO2 to persist for an extended period, further warming the planet, we do not know whether the environment that has nurtured our species can survive.

These high levels of CO₂ risk life as we know it

Carbon dioxide levels influence global temperatures. While CO₂ levels remain above about 300 ppm, the oven remains turned on –  and we are cooking our planet. (See my page on how fast the planet is heating up.) By maintaining high CO2 levels, we risk destroying life as we know it on Earth.

We need to DECREASE the alarmingly high CO2 level of 409 ppm, not increase it by 2 or 3 ppm each year.

Heating Influence of Greenhouse Gases

Consider the combined heating influence of long-lasting greenhouse gases in the atmosphere.

See Climate Dot Us. (Click on “Learn more” under the Greenhouse Gases.)

Between 1990 and 2024, the combined heating influence of these long-lasting greenhouse gases has increased by 54 percent.

The long-lived greenhouse gases are:

Naturally existing gases:

• Carbon dioxide (CO2)
• Methane (CH4)

Synthetic human-made compounds used in refrigerators, air conditioners, and spray cans:

• CFCs: Compounds containing chlorine, fluorine and carbon. We use these less because they damage the Earth’s ozone layer.
• HCFCs: Compounds containing hydrogen, chlorine, fluorine and carbon. We use these less because they damage the Earth’s ozone layer.
• HFCs: Compounds containing hydrogen, fluorine, and carbon. Developed to replace ozone-depleting substances, but they are potent greenhouse gases.

Created May 2014; Modified: 5 July 2026