California established targets that will result in reduced greenhouse gas emissions. The state’s forest sector has a critical role to play in this effort. Assembly Bill 1504 monitors the initial target established for California forests to sequester 5 million metric tons of carbon dioxide equivalent annually until 2020.
At the request of the state, Forest Service scientists compiled the best-available data on greenhouse gas emissions, stock and flux from California’s forest sector, identified critical gaps in data, and suggested strategies to reduce uncertainty in estimating the magnitude of stocks and flux within the forest sector. Forest ecosystem carbon stocks and flux are established using direct measurements on forested plots throughout the state of California as part of the USDA Forest Service Forest Inventory and Analysis program.
The researchers found that as of 2015, California’s forests remain net sinks, sequestering 33.6 million metric tons of carbon dioxide equivalent per year, excluding net flux from soils, forest floor organic litter, forest land conversions, non-CO2 emissions from wildfires, or harvested wood products. After accounting for these other sources (except harvested wood products), the rate of carbon sequestration is 32.8 million metric tons of carbon dioxide equivalent per year. Carbon stocks are just over 2 billion metric tons. However, in many forest types, current stocking levels stem from more than 100 years of fire suppression and may not represent stand densities that are resilient to disturbances common to California forests such as fire or pest outbreaks. They also found a net loss of forestland, primarily to developed land uses, contributed an estimated emission of 1.2 million metric tons of carbon dioxide equivalent annually.
This is the first in a series of annual reports to the California Board of Forestry and Fire Protection and is intended to assist the Board in evaluating and monitoring progress on meeting California’s forest sector carbon sequestration target.