Mapping wetlands of the North American boreal zone from satellite radar imagery

The accurate assessment of spatial and temporal distributions of wetlands can have a large impact in improving the estimates of the global net carbon exchange. This paper presents the methodology and sample results for the first large-scale wetlands map of the North American boreal zone, derived from JERS-1 and ERS-2 SAR imagery. The finished product will be a consistent baseline map, which can be subsequently used for time-series analyses when continuous satellite radar observations become available. The wetlands class maps are generated using a combination of optimization-based class rule definitions and a supervised classification algorithm. The wetlands class types are those defined by the Canadian Wetlands Classification System. Results are validated at a number of study sites and compared to existing local-scale wetlands maps.