The Positive and Negative Effects of Climate Change on Agriculture

Did you know?The U.S. agriculture sector produces approximately $300 billion per year in commodities. Weeds cause the largest loss in global crop production (34%), followed by insects (18%) and diseases (16%).

Plants require carbon dioxide to grow and could not survive without it. However, a warming climate resulting from increased emissions of carbon dioxide into the atmosphere will make it more difficult for farmers to grow crops and raise animals in some places. Climate change impacts agriculture directly through changes in the frequency and intensity of extreme weather events, and indirectly through the spread of stressors such as weeds, diseases and insect pests.

Heavier and more frequent precipitation events can damage plant roots and erode soils, which can prevent crops from growing. Extreme flooding events also harm crops and reduce yields. For example, a flood along the Mississippi River in 2008 that occurred right before the harvest period for many crops caused an estimated $8 billion loss for farmers.

Crops tend to grow faster in warmer temperatures, which reduces the amount of time that plants have to grow and mature. This can reduce crop yields when soils are not able to provide nutrients at the rates required for faster growing plants. Excessive heat coupled with drought in some areas is also a challenge, as reduced water availability makes it more difficult to keep up with the water demands of some crops.

Agriculture production in the United States is also largely impacted by weeds, insects and diseases. Controlling weeds alone costs the U.S. more than $11 billion per year. A climate with warmer temperatures, wetter conditions in some places, and increased carbon dioxide levels will increase the presence of weeds, pests and fungi that thrive under these conditions. For example, the European corn borer pest has increased its reproductive rates in the northern and southern Corn Belt due to higher winter and summer temperatures.