Forests and Climate Change Since the Kyoto Protocol took effect in 2005, the debate over global warming has once again heated up. While scientists generally agree that temperatures are getting warmer, there is little consensus over the degree that humans are having an impact, the potential consequences or what, if anything, can or should be done to lessen the effects. Long-term forecasting is notoriously complex, and current models indicate that average global temperatures could rise by as little as 1.5°C or as much as 4.5°C over the next century. According to the US Environmental Protection Agency, a 2°C shift in temperature "could shift the ideal range for many North American forest species by about 300 km (200 mi) to the north." If the change were slow, the forests could potentially adapt. But in just one century — "the species would have to migrate about two miles every year." In an effort to reduce the risks, countries around the world are working to cut their emissions of carbon dioxide (CO2), a greenhouse gas thought to be one of the causes. When the Kyoto Protocol took effect, thirty industrialized countries, including Canada, became legally bound to reduce net emissions of CO2 by 5 percent below 1990 levels. While the US chose not to ratify the treaty, it generates about 1/5th of the world's greenhouse gases and is seeking other ways to achieve reduction goals. The challenge for all countries is how to lower emissions without compromising economic growth-a challenge being met, in part, by forests. The Positive Role of Forests Forests help reduce the risk of climate change in several ways. First is the fact that growing forests act as "carbon sinks", absorbing CO2 from the atmosphere and releasing clean oxygen. Put simply, trees grow by taking the CO2 and converting it to sugars, which are used to build the wood. When a tree decays or burns, the carbon contained in the wood is released back into the environment, completing the cycle. A single tree can absorb many tons of CO2 over its lifetime. According to the Intergovernmental Panel on Climate Change, the world's forests and farmlands absorb about 8.4 billion tons of CO2 each year-but deforestation (where forests are converted for agriculture or urban development, or simply aren't regenerated) and destructive farming practices release about 5.8 billion tons back into the atmosphere. In North America, where forests have actually expanded by 10 million acres since 1990, sustainable forestry helps to maximize the role of carbon sinks. Because they're constantly regenerating, sustainably managed forests keep taking large amounts of CO2 out of the atmosphere, and wood products continue to store the carbon over the course of their lifetimes. While forest fires and insect infestations contribute to the negative side of the equation, wood from these areas can also be salvaged and turned into products. One of the biggest struggles, in reducing the risk of climate change, is how to lessen our reliance on fossil fuels such as coal and natural gas-which are major contributors of CO2. Another benefit of sustainable forestry is the fact that wood chips and other leftovers once considered waste are now burned for energy. Referred to as "biomass", these materials once released CO2 as they decayed in landfills or were burned as waste, but are now an environmentally friendly alternative to fossil fuels. Along these same lines, life cycle analyses show that wood requires less energy to manufacture and results in lower greenhouse gas emissions than either steel or concrete. So the use of wood as a substitute for other building materials is yet another way to reduce fossil fuel consumption. While scientists continue to debate the global warming risk and to what degree humans are having an impact, there is general consensus that countries should be doing what they can to minimize greenhouse gases in the atmosphere. Through sustainable management and the use of wood products, forests are an important part of the mix. Links: UN Framework Convention on Climate Change US Environmental Protection Agency: Forest Impacts Natural Resources Canada: Climate Change Pew Center on Global Climate Change