Editor’s Note: There was plenty of interest among attendees at the eighth annual National No-Tillage Conference in Des Moines regarding carbon credits. Because of these concerns, we asked Pete Hill to answer the most typical questions asked by no-tillers. Hill is an agronomist with Monsanto in Urbandale, Iowa, and has followed carbon sequestrian issues very closely.

Q: There’s lots of talk about global warming and greenhouse gases. What is it really about and is there any truth to what we hear?

A: Global warming is a real phenomenon that is partially a result of the increased emissions of certain gases. When methane, carbon dioxide and other gases accumulate at the highest levels of the earth’s atmosphere, the result is increased trapping of solar radiation (much like a greenhouse) and the earth becomes warmer.

Q: Where do these gases come from?

A: Several sources, but primarily from burning fossil fuels (in automobiles and tractors), use of fertilizers and changes in land use. Stash burning of forests, conversion of grasslands to cropland and conventional tillage are primary examples that release relatively high amounts of gases, especially carbon dioxide (CO2) into the atmosphere. Because CO2 is found in the greatest concentration and does more damage than the other gases, more time is being spent learning how to changes its levels.

Q: Is the concentration of these gases increasing every year?

A: Yes, especially with CO2. Without substantial changes in our way of living, the increases of gases will continue along with the warming…