Soil & Climate


What does the health of soil have to do with climate change?

We now know that healthy soil acts as a big storehouse for  carbon drawn down from the atmosphere and from decomposing organisms. So, healthy soil is vital for keeping the carbon cycle balanced and atmospheric carbon levels at a level that is healthy for life on earth. 

When the cycle is out of balance, carbon is released from the soil into the atmosphere more quickly. This can happen when soil is unhealthy or when plant-covered soil is disturbed. Let's think about why this happens.


Unhealthy soil sequesters less carbon and releases more into the atmosphere. Why?

Unhealthy soil does not have the nutrients to support as many plants as healthy soil. Fewer plants in the ground means that less photosynthesis occurs, which in turn means that less carbon is being pulled out of the air and stored in plant roots as carbon-based sugars. On the other side of the carbon cycle, unhealthy soil releases more sequestered carbon, especially when it is broken apart by tilling, plowing, or bulldozing.

How is the health of soil connected to climate? 

Climate is affected by the amount of carbon in the atmosphere.  Remember the carbon cycle? Healthy soil sequesters more carbon and slows its release back into the air. Unhealthy soil sequesters less carbon, and allows more carbon to escape into the air.

What role does carbon play in the Greenhouse Effect?

Carbon dioxide, the largest component of atmospheric carbon, is one of the gases that contributes to Earth's greenhouse effect. Like a greenhouse you might use to grow plants, the greenhouse effect allows heat from the sun in, but then traps the heat in our atmosphere. Earth is teeming with life because of its warmed atmosphere, but it's a careful balance. A decrease in atmospheric carbon dioxide means less heat is trapped, and the Earth will get cooler. An increase in atmospheric carbon dioxide means more heat is trapped, and Earth will get warmer. A warmer Earth has more extreme weather and climate patterns.

You experience a mini greenhouse effect in a car when you roll its windows up and down on a hot day. The temperature increases inside when you trap the heat by rolling windows up. The temperature inside cools when you let the hot air escape by rolling the windows down.

Questions to Consider

  • What is the difference in movement and balance of carbon  in carbon sequestration and carbon release?
  • What else do you notice about carbon release and carbon sequestration in this diagram and written description? 
  • Compare this diagram with the carbon cycle found on the Soil & Atmosphere page. How do they help tell the same story? 
  • How is water affected by the health of soil?