Multi-decadal to Millennial-scale Reconstructions of Global Biomass Burning and its Responses to Changes in Climate, Vegetation and Anthropogenic Forcings

Abstract:

Changes in the locations, timing, extent, and frequency of wildfires in many parts of the world are impacting ecosystems, people, and potentially climate. Paleofire records based on charcoal in sediments allow us to situate modern fires in their long-term context. Paleofire records also provide insights into the causes and impacts of past wildfires when analyzed in conjunction with other paleoenvironmental data and fire models. Time series and globally gridded reconstructions of biomass burning over the past 21,000, 2000, and 200 years are presented from a new version of the Global Charcoal Database. Analyses of the new data show that global biomass burning generally increased with increasing global temperatures over the past 21,000 years. Anthropogenic activities caused a sharp increase in fire, peaking in the 19^th and early 20^th centuries, followed by a rapid decline in the mid- to late 20^th century. Charcoal data from the past two decades show a sharp increase in biomass burning, particularly in North America.