Project Scope
The project has been divided into geographic mapping zones representing broadly similar ecological conditions. The mapping zones illustrated in the figure at right were created from aggregations of National Land Cover Dataset (NLCD) mapping zones originally derived from Bailey’s ecological sections (Homer and others 2004). The primary purpose of the mapping zones is to provide ecologically meaningful processing areas that are also efficient production units. Secondary consideration was given to significant administrative boundaries where they correlated closely with ecological unit edges. We recognize that application of the products will occur at a variety of ecological and administrative extents, and the analysis and summarization of data for the primary sponsors may have limited utility at larger scales. However, use at larger scales is both appropriate and technically feasible due to the spatial and thematic resolution inherent in the products. Furthermore, the spatially aggregate nature of fires and the ability to easily identify discreet events within the product sets allow for analysis ranging in extent from a single fire to multiple fires spanning space or time, or both. This is not to say that all analysis scales will be supported by these data. Indeed, as with all geospatial data, there are limits to effective application, and users will be encouraged to consider their analysis objectives and information needs relative to the spatial and thematic characteristics of the products.
Burn severity mapping is being conducted in two time phases. Fires occurring in 2004-10 are considered current and will be mapped and reported annually for the entire project extent. Historical fires occurring from 1984 through 2003 will be mapped, analyzed, and reported by mapping zone through the duration of the project. Mapping zones have been prioritized based on fire frequency, acres affected, and data availability. the figure at right also illustrates processing schedules for historical fires by mapping zone.
The historical range of this project (1984-2010) was determined on the basis of availability of remotely sensed data necessary to consistently characterize the extent and severity of individual fires. A longer historical period would afford the ability to more precisely analyze environmental and policy-based influences on wildland fire that are significant over decades and centuries. Recent land and fire management activities may be the most directly relatable influences on fire effects as depicted by these products. Beyond the scope of this project, but a valuable extension, would be the use of other, historically extensive sources of remotely sensed data to extend the fire effects record generated by MTBS, albeit with compromises in consistency.
Encyclopedia ID: p3602
