California is on track to meet statewide greenhouse-gas- (GHG-) emission targets for 2020, but will fall short of its goal for 2050 if additional policies are not enacted, a new spreadsheet model developed by Lawrence Berkeley National Laboratory indicates.

Funded by the California Air Resources Board, the California Greenhouse Gas Inventory Spreadsheet (GHGIS) shows the impact of combinations of state policies on state GHG and regional criteria-pollutant emissions. The Excel-based model includes representations of all GHG-emitting sectors of the California economy. It was calibrated using data and projections from state agencies and other sources.

The model calculates emissions of three criteria pollutants—reactive organic gases, nitrogen oxides (NOx), and fine particulates—statewide and for the South Coast Air Basin and San Joaquin Valley.

Three scenarios were modeled: (1) all committed policies, (2) additional, uncommitted policy targets, and (3) potential technology and market futures. For all three scenarios, California was shown to be able to meet 2020 statewide GHG targets. By 2030, a plausible range of statewide GHG emissions was shown to be 208 to 396 megatons of carbon-dioxide (CO2) equivalent per year. The 2050 GHG target of 85 megatons of CO2 equivalent per year was found to be out of reach under each of the scenarios. In particular, NOx emissions were significantly above the estimated targets.

To download the project report, “Estimating Policy-Driven Greenhouse Gas Emissions Trajectories in California: The California Greenhouse Gas Inventory Spreadsheet (GHGIS) Model” by Jeffery B. Greenblatt, go to