Radar Backscatter Is Not a 'direct Measure' of Forest Biomass. Woodhouse, I. H., Mitchard, E. T. A., Brolly, M., Maniatis, D., & Ryan, C. M. 2(8):556–557.
Radar Backscatter Is Not a 'direct Measure' of Forest Biomass [link]Paper  doi  abstract   bibtex   
[Excerpt] Accurately mapping forest carbon now has important financial and livelihood implications for many smallholder farmers, businesses, investors, land-use projects and governments. The urgent need to reduce uncertainties in the carbon cycle, the increasing focus on global sustainable forestry, and the international agenda on Reducing Emissions from Deforestation and Forest Degradation (REDD+) has led to the creation of new communities clamouring for robust methods to map forest aboveground biomass (AGB). Satellite radar is often proposed as the best tool to overcome the substantial spatial, frequency and cost limitations of allometric-based field surveys. There is ample evidence that demonstrates the general sensitivity of long wavelength (L-band and larger) radar backscatter to AGB, up to a signal-saturation point1, 2, 3, 4, and we believe that radar is typically the best satellite-based remote-sensing tool for mapping forest extent5, estimating forest structural variability1, 6, and detecting deforestation and degradation2. However, we are concerned that in some instances data have been over- or misinterpreted, often to match expectations, and this is leading to the case for imaging radar being overstated. To be specific, we contest the use of the term 'direct measurement'5, 7, 8 to describe the application of radar backscatter intensity to map forest AGB. Although radar may employ a direct approach, whereby the signal is directly converted to AGB, it is not a direct measurement, which implies an unambiguous and well-defined relationship, an assertion that is neither expected from theory nor supported by measurements. We believe the use of this term in high-impact journals is creating confusion among policymakers as to the realistic potential of radar as a low-cost operational alternative to field inventories; it must be seen as a useful complement, not an alternative.
@article{woodhouseRadarBackscatterNot2012,
  title = {Radar Backscatter Is Not a 'direct Measure' of Forest Biomass},
  author = {Woodhouse, Iain H. and Mitchard, Edward T. A. and Brolly, Matthew and Maniatis, Danae and Ryan, Casey M.},
  date = {2012-07},
  journaltitle = {Nature Climate Change},
  volume = {2},
  pages = {556--557},
  issn = {1758-678X},
  doi = {10.1038/nclimate1601},
  url = {https://doi.org/10.1038/nclimate1601},
  abstract = {[Excerpt] Accurately mapping forest carbon now has important financial and livelihood implications for many smallholder farmers, businesses, investors, land-use projects and governments. The urgent need to reduce uncertainties in the carbon cycle, the increasing focus on global sustainable forestry, and the international agenda on Reducing Emissions from Deforestation and Forest Degradation (REDD+) has led to the creation of new communities clamouring for robust methods to map forest aboveground biomass (AGB).

Satellite radar is often proposed as the best tool to overcome the substantial spatial, frequency and cost limitations of allometric-based field surveys. There is ample evidence that demonstrates the general sensitivity of long wavelength (L-band and larger) radar backscatter to AGB, up to a signal-saturation point1, 2, 3, 4, and we believe that radar is typically the best satellite-based remote-sensing tool for mapping forest extent5, estimating forest structural variability1, 6, and detecting deforestation and degradation2.

However, we are concerned that in some instances data have been over- or misinterpreted, often to match expectations, and this is leading to the case for imaging radar being overstated. To be specific, we contest the use of the term 'direct measurement'5, 7, 8 to describe the application of radar backscatter intensity to map forest AGB. Although radar may employ a direct approach, whereby the signal is directly converted to AGB, it is not a direct measurement, which implies an unambiguous and well-defined relationship, an assertion that is neither expected from theory nor supported by measurements. We believe the use of this term in high-impact journals is creating confusion among policymakers as to the realistic potential of radar as a low-cost operational alternative to field inventories; it must be seen as a useful complement, not an alternative.},
  keywords = {*imported-from-citeulike-INRMM,~INRMM-MiD:c-12733845,ambiguity,biomass,data,data-transformation-modelling,definition,derived-data,field-measurements,forest-biomass,forest-resources,radar,semantics},
  number = {8}
}

Downloads: 0