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Chapter 34 : FIRE AND CLIMATE - Using the past to predict the future. Chapter 34 : FIRE AND CLIMATE - Using the past to predict the future: Using the past to predict the future
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International audience. Fire has been an important component of ecosystems since the first terrestrial plants appeared, with fire records dating as far as to 420 million years ago. Fire is present in most of Earth’s ecosystems except in areas of sparse vegetation and near the poles. Human manipulation of fire for land-clearing and recreation, as well as fire suppression practices, has disrupted the natural pattern of fire activity in many forested regions. In addition, anthropogenic climate change is expected to further alter global fire occurrence, with important consequences for species distribution, ecosystem integrity and function, atmospheric greenhouse gas balance, and human safety. Characterizing the range of fire regime modifications remains a major challenge owing to the large interannual variability in area burned that tends to mask long-term and subtle changes. In this chapter, we outline the physical processes of fire in relation to the forest environment and climate. We also review the methods used in fire history reconstructions as well as results from fire history reconstructions and modeling. The best proxy records for longer term fire reconstructions are tree-ring and lake sediment records. Finally, our discussion focuses on fire history derived from these two proxy types at multiple sites in boreal, temperate, and tropical regions.