In 2013, the California Air Resources Board (CARB) began the development of a new Compliance Offset Protocol for Rice Cultivation. This is the first agriculture land based offset protocol to be considered under the ARB compliance program. Rice producers can play a key role in helping California meet the emissions reduction goals required by Assembly Bill 32 through a reduction in methane emissions. Offsets are a crucial part of the cap-and-trade program in AB 32 because they provide compliance entities with less costly way to satisfy their cap.
The DNDC biogeochemical process model will be used to quantify changes in rice methane emissions due to the eligible practices. Initially projects would be limited to the major rice growing regions in California and the Mid-South (Arkansas, Missouri, Mississippi, Louisiana, and Texas) for which the DNDC model has been calibrated with field measurements of methane emissions. ARB is considering the following management changes as eligible practices for offset: 1) replacing wet seeding with dry seeding, 2) early drainage at the end of growing season, and 3) rice straw removal after harvest; and 4) intermittent flooding.