Estimating Net Carbon Emissions and Agricultural Response to Potential Carbon Offset Policies

Abstract

In this study, we developed a technique for estimating soil C sequestration from crop production with detailed spatial differences in production practices, tillage effects, and soil textures often overlooked when modeling state‐level implications of climate change policies. The model also tracks C equivalent (CE) emissions from fertilizer, fuel, and agricultural chemical use. Using Arkansas as an example, a model that maximizes crop returns to producers in conjunction with C offset payments allowed estimation of probable changes in county‐level cropping patterns and income as a result of varying C prices. While income ramifications of a C‐offset climate change policy are positive, significant uncertainty about resultant greenhouse gas (GHG) effects are demonstrated. Crops included were corn (Zea mays L.), cotton (Gossypium hirsutum L.), grain sorghum [Sorghum bicolor (L.) Moench], soybean [Glycine max (L.) Merr.], rice (Oryza sativa L.) and wheat (Triticum spp.). As a result of this detailed analysis, two caveats are that (i) policy recommendations hinge on a baseline scenario that would change with changes in input and output price levels, with these interactions not modeled within, and (ii) monitoring costs of a C‐offset market could be significant.