Excess CO2 Damages Agriculture More Than It Helps Crops Grow
Drought Ravages Missouri Cornfield. Used by permission of Gary Braasch
One Good Ear in Drought Ravaged Missouri Cornfield. Used by permission of Gary Braasch

Sarah A. Green, Professor of Chemistry at Michigan Technological University explains:

“Plants need four key things to grow: light, water, carbon dioxide, and fertilizer. Anyone who has a farm, garden, or house plant knows that plants need the right balance of all of these things. No amount of fertilizer will help a plant that has no water.

Scientists studying the impacts of climate change on agriculture look at all aspects of the system. Of those four factors, light will change the least. But water is a big concern. Changing the climate changes where and when rain falls. Some areas become more wet and other areas become more dry. Rain might come too early or too late for crops. Hotter air holds more water, so when it rains, it pours. Floods wash away seeds and plants.

Picture of 4 items essential to plant growth
(CC) BY 0 pixabay.com OpenClips enquiries@uqx.uq.edu.au

Climate change can cause problems for fertilizer because heavy rain washes it out of the fields and down rivers. A common myth ignores that fact and claims that ‘CO2 is a plant food.’ This is an oversimplification. It chooses a single piece of a complicated problem and ignores the other parts. It’s like saying ‘humans need calcium so all you need to live on is ice cream’.

Carbon dioxide makes plants grow faster when they are in an ideal environment, like inside a greenhouse, where they have the right amount of water and fertilizer. But for the basic needs of plants, we need to consider carbon dioxide AND water.

It’s not enough to have the basic necessities of life. Plants also have to be safe from danger. One big danger for plants is hot temperatures. Our major agricultural crops have ideal temperature ranges. As the temperature goes up, crop yields go down. Plants are especially sensitive to extremely hot days.

Pictures of harmful bugs
Colorado Potato
beetle (CC) 0 ars.usda.gov Scott Bauer; USDA ARS
* Grapevine moth (CC) BY flickr.com/photos/wildreturn/13813642994/
Andy Reago & Chrissy McClarren enquiries@uqx.uq.edu.au; * Fusarium
verticillioides 01
(CC) 0 en.wikipedia.org Taragui enquiries@uqx.uq.edu.au

Some other creatures love hot weather. Unfortunately, many of them are pests like the Colorado potato beetle, the European grapevine moth, and a nasty wheat blight called FHB or fusarium head blight. Some pests, like FHB, even prefer the taste of crops that have grown with more CO2 and grow faster. Many pests are migrating north as the climate warms, into areas where they’ve never been seen before.

The overwhelming consensus among agricultural scientists is that the negative impacts of climate change on crops far outweigh the small benefit that plants gain from extra CO2.”

Additional heat will harm Montana’s agricultural production, increasing soil-dryness and surface-water loss, offsetting benefits of longer growing seasons. [5] Days over 100ºF will double by mid-century.

Since there is a 10% decline in wheat, corn, and rice yields for every 1 degree Celsius rise in temperature during growing periods, as temperatures rise our ability to raise food will diminish. [6a]  [6b at p. 8] Scientists predict that if we continue burning more and more fossil fuels, we’ll see around 4 degrees Celsius (7.2° F) warming by the end of this century.

So in summary, even though plants benefit from CO2 and need it to thrive, plants are also negatively impacted by increased CO2 levels. Temperatures are increasing as a result of higher CO2 levels. As temperature goes up, crop yields go down. Additionally, pests that thrive in hot weather become a danger to plants. Therefore, the harm done by increased CO2 levels far outweigh the benefit that plants gain from extra CO2. That’s why some farms (like the solar dairy pictured below) are taking steps to limit greenhouse gases.

Photo of Solar Dairy Farm
Solar Dairy Farmer in Bavaria, Germany — Doing Something To Reduce CO2. Photo used by permission of Gary Braasch.

Global warming is putting the squeeze on bumblebees. In the most comprehensive study ever conducted of the impacts of climate change on critical pollinators, scientists ( published in Science )have discovered that global warming is rapidly shrinking the area where these bees are found in both North America and Europe, eliminating the southern 185 miles of their range if they cannot move uphill.

Wind can provide 20% of US electricity by 2030 providing farmers and ranchers $650 a year in land leases
Click the picture to sign the 80% renewable electricity by 2050 petition & promote more renewable energy land lease money going to farmers and ranchers.

Home of Montana (MT) Community Affordable Renewable Energy Saves; Paid for by MTcares, Inc., Pam Ellis, Treasurer, Billings MT 59105