Boreal forest ecosystem characterization with SIR-C/XSAR

A National, Detailed Map of Forest Aboveground Carbon Stocks in Mexico

“…The observed correlation with forest biophysical attributes and saturation levels differed significantly across different forest types and environmental imaging conditions, even for a given wavelength. In the case of L-band, the reported saturation levels with respect to aboveground biomass retrieval varied between 40 and 180 t/ha [19,[23][24][25][26][27][28][29][30][31]. A spaceborne P-band SAR, which would be less affected by saturation at higher biomass levels, is planned for launch in the coming years in the frame of the Earth Explorer Program of the European Space Agency (ESA) [32].…”

“…To use SAR data for large-area forest mapping purposes, the sensitivity of the measurements to environmental and weather effects, such as precipitation and the associated canopy and soil moisture variations or freeze/thaw transitions, need to be accounted for [27,29,[62][63][64][65][66][67][68][69][70][71][72][73]. Ideally, models relating radar measurements to the forest biophysical attribute of interest are calibrated adaptively to account for temporal and spatial variations in the imaging conditions [15,18,19].…”

Mapping forest clearcuts using radar digital imagery: A review of the Canadian experience

“…Canadian radar satellite, RADARSAT. There are also some studies using the SIR-C/X-SAR prototype, which produces X-VV and multi-polarized C and L-band images (Ranson et al 1995, Ranson andSun 1997).…”

Sensitivity of Multi-Source SAR Backscatter to Changes in Forest Aboveground Biomass

“…A series of studies suggested that a widely applicable relationship exists between biomass and backscatter from L-band SAR for woody vegetation with lower levels of biomass (≤150 Mg·ha −1 ) in tropical [6][7][8], temperate and boreal biomes [9][10][11][12][13]. Both airborne and spaceborne systems were involved in these studies, including airborne instruments such as AIRborne SAR (AIRSAR) and the Uninhabited Aerial Vehicle SAR (UAVSAR) developed by the National Aeronautics and Space Administration (NASA), Experimental-SAR (ESAR) operated by the German Aerospace Center (DLR), as well as spaceborne instruments such as the first Earth-orbiting satellite SEASAT, Spaceborne Imaging Radar-C and X-B and SAR (SIR-C/XSAR), Japanese Earth Resources Satellite 1 (JERS-1), and Phased Array type L-band SAR (PALSAR) on board the Advanced Land Observing Satellite (ALOS) operated by the Japan Aerospace Exploration Agency (JAXA).…”

“…Both airborne and spaceborne systems were involved in these studies, including airborne instruments such as AIRborne SAR (AIRSAR) and the Uninhabited Aerial Vehicle SAR (UAVSAR) developed by the National Aeronautics and Space Administration (NASA), Experimental-SAR (ESAR) operated by the German Aerospace Center (DLR), as well as spaceborne instruments such as the first Earth-orbiting satellite SEASAT, Spaceborne Imaging Radar-C and X-B and SAR (SIR-C/XSAR), Japanese Earth Resources Satellite 1 (JERS-1), and Phased Array type L-band SAR (PALSAR) on board the Advanced Land Observing Satellite (ALOS) operated by the Japan Aerospace Exploration Agency (JAXA). Ranson et al [10] investigated the use of multi-frequency, multi-polarization and multi-season image data from SIR-C/XSAR to map forest cover type and estimate aboveground biomass for a Boreal Ecosystem-Atmosphere Study (BOREAS) site in Saskatchewan, Canada. Santos et al [6] utilized the L-HH channel of JERS-1 data in tropical forest-savanna contact zones, and found that the logarithmic and sigmoid functions were adequate to explain the SAR backscatter as a function of forest biomass.…”