California Institute for Energy and Environment (CIEE)

The project in this report sought to quantify the baseline of changes in carbon stocks on forest and agricultural lands in Arizona for the 1990s. These baselines provide an estimate of the emissions and removals of greenhouse gases attributable to changes in the use and management of land and are useful for identifying where major opportunities could exist in Arizona for enhancing carbon stocks and/or reducing carbon sources to potentially reduce greenhouse gas emissions.   The analysis revealed that forests were responsible for a net removal of carbon dioxide from the atmosphere of 0.9 million metric tons of carbon dioxide per year (MMTCO2/yr) between 1987 and 1997, and that agricultural lands were responsible for a net emission of 0.04 MMTCO2/yr. On non‐federal lands emissions from forests caused by development were estimated at 0.0145– 0.0152 MMTCO2/yr, and between 1990 and 1996 154,000 acres of forest and rangeland were burned by fires with an estimated emission of 0.47 MMTCO2eq/yr. Nitrous oxide (N2O) and methane (CH4) emissions (in CO2 eq) from agricultural lands are more than 100 times higher than carbon emission due to land‐use change.