E. Kasischke, G. Hurtt, J. Hicke, S. Goward, J. Masek Assessing the Impacts of Major Disturbance Events on North America’s Forest Carbon Budget During the Early 21st Century E. Kasischke, G. Hurtt, J. Hicke, S. Goward, J. Masek NACP 4th AIM 6 Feb 2013

Results from recent research Increased burned area and fire severity has resulted in the boreal forests in the Yukon River Basin switching from a net C sink to a net source of carbon Increased insect mortality in the western U.S. has increased the C source strength of the forests in this region Increased burned area in the western U.S. has increased the C source strength of the forests in this region Increased hurricane activity in the southeast U.S. has shifted the forests in this region from a net C sink to a net C source

Conterminous US (Pan et al.) 179 239 60 1990 to 1999 2000 to 2007 Change 1990s to 2000s Conterminous US (Pan et al.) 179 239 60 Canada managed forests (Pan et al.) 26 10 -16 Total 205 249 44 NACP/CarboNA Results Yukon River Basin Fires (Yuan, Kasischke et al.)   -15 Western U.S. Fires (Ghimer, Williams, et al.) -10 Western US Insects (Edburgh, Hicke et al.) Eastern US Hurricanes (Fiske, Hurtt et al.) Net Disturbance Impacts -50 Units are Tg C/yr

Suggested Future Activities Paper focused on synthesizing results of research on natural disturbance impacts on forest C sink strength Short term impacts vs. long-term legacies Modeling synthesis focused on impacts of recent natural disturbances, including mega-disturbances (fire, insects, hurricanes) and diffuse disturbances (drought, forest die back, wind damage, etc.) Modeling approaches (Fire emissions, inventory-based models, net biome production models) Regional to continental scale models

Societal Importance of Natural Disturbances Climate Policy and Negotiations Direct impacts on society Threats to life, health, and property Huge impacts on local and regional economies based on wood products Effect a wide range of other ecosystem services Stinson el 2011 See Tony Lempriere talk from Wed. a.m.