Climate fact check: Carbon dioxide is good for greenhouses, bad for the planet


Greenhouses on a farm. Even though carbon dioxide is good for greenhouses by boosting plant yields, high concentrations of the gas are not good for the planet.

Photo credit: File | Nation Media Group

The invention of the greenhouse has been credited to a French botanist called Charles Lucien Bonaparte, who is said to have built the first one in Leiden, Holland, in the 17th century to grow medicinal tropical plants.

Now, they are often used to raise plants from seed, under ideal growing conditions throughout the year. Modern greenhouses also practise carbon dioxide enrichment to boost the yield of their crops.

However, this has been contentious, with some people believing that because greenhouses use carbon dioxide to promote plant growth, carbon dioxide must be good for the planet.

This is, however, false, because experts state that even though carbon dioxide boosts plant yields, high concentrations of the gas are not good for the planet.

According to MIT Climate, plants may grow faster and bigger with extra carbon dioxide, but only when every other condition such as soil nutrient and water are met.

“Although plants need carbon dioxide to grow, their success in very high-carbon environments is not guaranteed. Not all plants like extra carbon equally. And for those carbon aficionados in the plant kingdom, CO2 is not the only factor that controls growth. As any aspiring green thumb knows, plants need the right balance of water and soil nutrients to translate extra carbon dioxide into growth,” says MIT Climate.

“This is a problem; given the way our climate is trending. Climate change, driven by excessive CO2 in the atmosphere, deepens droughts in places like the American West. That reduces the water supply for plants there while simultaneously increasing the risk of catastrophic wildfires. In other places, plants will have to cope with more frequent disasters like flooding and heat stress, exposure to saltwater from rising seas, and an increase in pests that enjoy warmer winters,” it adds.

Even though carbon dioxide benefits plants in a controlled environment, carbon dioxide in the open atmosphere traps heat, leading to global warming and climate change, which potentially results in heatwaves, droughts, wildfires, melting of icebergs and increase of sea levels, among others.

“Climate change is bringing different types of challenges to each region of the country. Heat waves, heavy downpours, and sea level rise pose increasing challenges to many aspects of life in the Northeast. Infrastructure, agriculture, fisheries, and ecosystems will be increasingly compromised.  In the Northwest, changes in the timing of peak flows in rivers and streams are reducing water supplies and worsening competing demands for water. Sea level rise, erosion, flooding, risks to infrastructure, and increasing ocean acidity pose major threats,” says Nasa.

“In Southeast, sea level rise poses widespread and continuing threats to the region’s economy and environment. Extreme heat will affect health, energy, agriculture, and more. For the Midwest, extreme heat, heavy downpours, and flooding will affect infrastructure, health, agriculture, forestry, transportation, air and water quality, and more. In Southwest, climate change has caused increased heat, drought, and insect outbreaks. In turn, these changes have made wildfires more numerous and severe. The warming climate has also caused a decline in water supplies, reduced agricultural yields, and triggered heat-related health impacts in cities. In coastal areas, flooding and erosion are additional concerns,” adds Nasa.

- This fact check was produced by Nation with support from Code for Africa’s Pesa Check, International Fact Checking Network, and African Fact Checking Alliance Network