|Climate, Biodiversity, and Forests - Issues and Opportunities Emerging from the Kyoto Protocol (WRI, 1998, 40 pages)|
|Technical Concerns Associated with Measuring and Verifying Forest and Land-Use Change Emissions and Reductions|
Lastly some question the ability to estimate accurately carbon losses and gains from vegetation and soils due to land-use and management strategies.
At the project level, mounting evidence indicates that measurement uncertainty is overstated.80 The Intergovernmental Panel on Climate Change (IPCC) indicates a high confidence that site-level estimates of net carbon conserved or sequestered under specific management schemes are more certain than large-scale estimates of carbon fluxes, such as those at the national level.81 Thus, project-based efforts, if well monitored, could yield measurable carbon losses and gains due to project activities, The IPCC defines high confidence as a high degree of consensus among the report's authors based on "substantial" evidence.82
The main hurdle facing accurate carbon accounting is the cost of obtaining the measurements. Any project or effort can be monitored and measured closely, but increasing accuracy raises costs. While there continues to be uncertainty regarding forest soil carbon, the majority of pilot offset projects have not included soil in their net carbon estimates.
Studies have pointed to both data sources and methods for tracking carbon flows over larger areas, which is required for national inventories. One U.S. study for example, combined regional forest inventories undertaken by the U.S. Forest Service with ecosystem studies to estimate carbon storage for major forest types in the United States." These data and methods could be used to track changes in carbon storage. However, some Annex I countries may lack the appropriate monitoring systems to track changes in land use and their subsequent greenhouse gas emissions and reductions, especially if they are not timber producers, Also, further research is required to determine greenhouse gas flows over time in forests under various management schemes. Measurement accuracy remains a key issue for improving national inventories of emissions and reductions from forests and land-use change.