Large-Scale Mapping and Monitoring of Terrestrial Ecosystems with the NISAR Mission

Abstract:

Set to launch at the early part of the next decade, the NI-SAR mission will measure globally the spatial distribution of vegetation and biomass to understand changes and trends in terrestrial forest and wetland ecosystems and their functioning as carbon sources and sinks, and characterize and quantify changes resulting from forest disturbance and recovery. Novel technology provides for unprecedented forest monitoring and ecosystem structure assessment with NI-SAR based on a 12-m reflector L-band scan-on-receive configuration (known as SweepSAR), which allows for a greater than 240 km swath and unprecedented global wall-to-wall coverage with a 12-day repeat cycle at pixel resolutions better than 25 m. Data from the mission will be made freely available through NASA’s open data policy. Latency for basic data products such as co- and cross-pol reflectivity is expected to be less than several days. Through this capability, the mission will provide a crucial tool for forest carbon assessment and monitoring, important for treaties like REDD+, forest inundation monitoring, improved carbon stock estimates for low biomass regions, and monitoring of land-cover conversion to and from agricultural production. In this paper we summarize the capability of NI-SAR’s observing strategy, anticipated approaches for monitoring forests, wetlands, and agricultural lands and their changes. We review the science background, science objectives and requirements, and data products stemming from the mission.