In global warming circles, carbon dioxide is the bogey man, the cause of all evils. CO2 is another Vladimir Putin, blamed for rising gasoline prices and President Biden’s 8.5 percent inflation. Just as Putin isn’t responsible for consumer prices, which began rising shortly after Biden took office, CO2 may not be the bogey man hiding under the beds of Greta Thunberg and Al Gore, ready to pop out and consume the world.
Is CO2 really the bogeyman? Is it a friend or foe of planet Earth? The answer may surprise you.
CO2 is one of several greenhouse gasses. Water vapor however is the largest contributor to the Earth’s greenhouse effect. CO2 is also plant food. Think back to high school biology and photosynthesis. Water, CO2, and sunlight combine to produce carbohydrates and oxygen, the carbohydrate being the plant food.
CO2 is a relatively small percentage of air, 0.035% to be exact, less than one-half of one percent of the air around us. CO2 levels can vary significantly, from less than 400 parts per million outdoors to over 1000 inside a crowded room. Submarine crews tolerate CO2 levels of up to 8000 parts per million without adverse health effects.
Although a minor component of our atmosphere, CO2 is essential for plant growth. A 100 percent increase in CO2 levels increases plant growth from 22-41 percent, depending on plant type. Aside from CO2, temperature also affects plant growth. Warmer temperatures translate to higher growth rates, assuming the other photosynthesis ingredients remain in place.
Finally, plants have tiny holes on the underside of their leaves called stomata, a “mouth” through which plants ingest CO2. When the CO2 levels are higher, the stomata don’t need to open as wide to get the CO2 they need. Plants also lose water through these stomata so smaller stomata openings mean less water loss. The bottom line is that higher CO2 levels in the air mean plants lose less water, need less water to thrive, and can grow in drier, otherwise inhospitable environments.
This means that higher CO2 levels with slightly warmer temperatures increase the productivity of most plants. The result is a greening of the planet, combating the effects of fires, deforestation, pest outbreaks, and other attacks on Earth’s vegetation. As the planet greens, dry climates become fertile, supporting plant life which in turn feeds both humans and animals.
This CO2 fertilization correlated with an 11 percent increase in foliage cover from 1982-2010 across many arid regions of the world. Think of the resulting benefits, including the reduction of hunger, disease, and poverty in Africa and the Middle East. These are virtuous goals and far more achievable if nature is allowed to take her course as compared to climate activists holding concerts and wearing colored ribbons on their lapels.
