The North American Commission for Environmental Cooperation (CEC) has released a tool it says can help solve one of the biggest uncertainties in the science of carbon budgeting: how much carbon is stored in, or released by, forests.
“Globally, forests are the largest land-based carbon sink, and over the past two decades have removed more than one-quarter of the emissions worldwide from the burning of fossil fuels,” the CEC notes in its report on a project that engaged the national forest services of Canada, the United States, and Mexico.
The tri-national effort examined drivers of forest carbon dynamics such as human and natural disturbances, land use and land-use change, as well as climate and environmental changes. It overcame divergent observation and recording protocols in the three nations, the CEC said, and developed “analytical tools that integrate data from forest inventories, ground-plot measurements and intensive site studies, soil carbon measurements, and remote sensing of land cover and its changes over time.” Models the agency describes as “powerful and flexible tools for the integration of data from multiple sources” imported remote sensing data to track annual land use changes at 30-metre resolutions.
The model was given a test run in three regions: Mexico’s Yucatan Peninsula, the Nez Perce–Clearwater National Forest in Idaho, and British Columbia’s central Prince George region. In the Yucatan, it found a 2.5% reduction in the rate of deforestation from 2011 on will deliver a 150-Mt annual reduction in greenhouse gas emissions by 2030.
How much carbon is stored in, sequestered by, or released from forested lands under different circumstances such as forest fires or forest clearing has long been contested, and has bedeviled efforts to conclude a satisfactory international agreement to incorporate Reduced Emissions from Deforestation and Forest Degradation (REDD) in a global climate plan. Existing forest carbon models, the CEC shows, can show the same forest to be either a carbon sink or a carbon source. Its team claims, however, that with enough information available, its highly integrative “Tier 3” models “can generate the data required for regional and national estimates of GHG emissions and removals in the forest sector.”
