Today, some people portray carbon dioxide (CO2) as an enemy of the earth. We hear negative things about it in almost every aspect of life, including in schools, TV shows, and the mainstream media.
But is CO2 really a villain?
I was a little kid when I first came to know that in photosynthesis plants inhale CO2 and exhale oxygen. I also understood why plants shrivel and die with too little of it but grow better and better as CO2 levels rise. That’s why CO2 is not a pollutant.
Twenty-five years later, the truth about CO2 has not changed, but some people unabashedly claim that CO2 levels threaten earth’s biosphere. So, to understand why it’s mistaken to call the increase in atmospheric CO2‘dangerous,’ let’s check some facts.
Carbon dioxide is an invisible, colorless, odorless gas that is indispensable to life on earth. It is the elixir of life. Without it, life as we know it would be impossible.
An integral part of our environment, 98 percent of all CO2 is in the oceans and land (soil and plants). The amount of CO2 in the atmosphere is just 2 percent. Of that 2 percent, nature put about 57 percent there, and humans about 43 percent.
In the interglacial periods of the distant past, atmospheric CO2concentration—on the order of several thousand parts per million (ppm)—was much higher than it is today. It plummeted during ice ages to about 180–200 ppm, drastically reducing plant growth. In the roughly 20,000 years since the last ice age, CO2 concentration rose to about 280 ppm before the Industrial Revolution, but even then plant growth remained poor. The increase in CO2 concentration to about 400 ppm today is not harmful. Far from it, it has been tremendously beneficial for plants and, because we depend on plants for food, animals and humans.
Increased CO2 concentration is directly proportional to plant growth rates. Many important plant species show marked increase in their growth patterns when CO2 concentration increases.