Two decades of forest disturbance and regrowth across the United States evaluated using the Landsat record for the North American Carbon Program

Forest disturbance and regrowth are assumed to be significant forces modulating North American carbon balance. Quantifying the carbon fluxes of forest changes requires the changes be assessed with appropriate spatial and temporal details. Landsat imagery accumulated since 1972 provides a unique data source for evaluating these processes over the last 30+ years. Through a NASA funded project -- "North American Forest Disturbance and Regrowth since 1972 (NAFD)", Landsat time series stacks (LTSS) have been assembled for 29 locations selected to represent United States dynamics. For each selected location, the LTSS is being used to map forest disturbance and regrowth with a nominal temporal interval of 2 years from 1972 to 2005. In this talk we will present the results we have derived for the TM/ETM+ era of the Landsat missions - from 1984 to 2005. Specifically, we will provide an assessment of the spatial and temporal characteristics of the changes mapped for each site. We will also discuss the regional variations in patterns derived from these sites. Results from this study will provide a basis for improved quantification of carbon fluxes arising from forest disturbance and regrowth across the United States. The derived forest change products will most likely also be highly valuable for forest resources management, ecosystem monitoring, and ecological applications.