Climate change caused by the enhanced greenhouse effect is one of the most significant global environmental issues. Increased emissions of GHG to the atmosphere, most notably CO2 , are considered the main cause of global climate change. Increasing energy consumption, a reliance on fossil fuels to meet these needs, and deforestation related to land use change are the main sources of increasing atmospheric CO2.
The ability of biomass to make a significant contribution to the stabilization of atmospheric CO2 concentrations through its utilization as an energy source and the preservation of terrestrial biomass stocks has lead to its inclusion in global policy developments.
Global concern over the increase in atmospheric GHG concentrations and the acknowledgment that human activity is leading to climate change led to nations recognizing the need for international effort. The United Nations Framework Convention on Climate Change (UNFCCC) was agreed at the Rio Earth Summit in 1992 and entered into force in 1994. Parties agreed to report on GHG emissions and to take action to mitigate climate change by limiting those emissions and to protect and enhance GHG sinks and reservoirs.
The Kyoto Protocol to the UNFCCC, developed in 1997, set the relatively short-term target for developed countries and countries with economies in transition to stabilize their combined GHG emissions, in CO2 equivalents, to 5.2% below 1990 levels during the first commitment period 2008–2012. Actions that enhance carbon stock in biomass and soil, such as reforestation and altered management in forestry and agriculture, can be used as credits to offset GHG emissions to meet commitments under the Kyoto Protocol.
Biomass can address the issue of global climate change in three ways:
(1) bioenergy produced from biomass can replace fossil fuels, directly reducing emissions;
(2) biomass can sequester carbon as it is growing, increasing the terrestrial carbon stock; and
(3) biomass products can substitute for more energy intensive building products, reducing the emissions associated with production of these materials and additionally increasing the carbon stock in wood products.
Offsetting fossil fuel emissions with sequestration in biomass and reducing fossil fuel emissions through substitution of renewable bioenergy are likely to be key factors in the ability of countries to achieve their reduction commitments under the Kyoto Protocol.
